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[ [ "Control character" ], [ "Introduction", "In computing and telecommunication, a '''control character''' or '''non-printing character''' ('''NPC''') is a code point in a character set that does not represent a written character or symbol.", "They are used as in-band signaling to cause effects other than the addition of a symbol to the text.", "All other characters are mainly ''graphic characters'', also known as ''printing characters'' (or ''printable characters''), except perhaps for \"space\" characters.", "In the ASCII standard there are 33 control characters, such as code 7, , which rings a terminal bell." ], [ "History", "Procedural signs in Morse code are a form of control character.A form of control characters were introduced in the 1870 Baudot code: NUL and DEL.The 1901 Murray code added the carriage return (CR) and line feed (LF), and other versions of the Baudot code included other control characters.The bell character (BEL), which rang a bell to alert operators, was also an early teletype control character.Some control characters have also been called \"format effectors\"." ], [ "In ASCII", "Early symbols assigned to the 32 control characters, space and delete characters.", "(ISO 2047, MIL-STD-188-100, 1972)There were quite a few control characters defined (33 in ASCII, and the ECMA-48 standard adds 32 more).", "This was because early terminals had very primitive mechanical or electrical controls that made any kind of state-remembering API quite expensive to implement, thus a different code for each and every function looked like a requirement.", "It quickly became possible and inexpensive to interpret sequences of codes to perform a function, and device makers found a way to send hundreds of device instructions.", "Specifically, they used ASCII code 2710 (escape), followed by a series of characters called a \"control sequence\" or \"escape sequence\".", "The mechanism was invented by Bob Bemer, the father of ASCII.", "For example, the sequence of code 2710, followed by the printable characters , would cause a Digital Equipment Corporation VT100 terminal to move its cursor to the 10th cell of the 2nd line of the screen.", "Several standards exist for these sequences, notably ANSI X3.64.But the number of non-standard variations in use is large, especially among printers, where technology has advanced far faster than any standards body can possibly keep up with.All entries in the ASCII table below code 3210 (technically the C0 control code set) are of this kind, including CR and LF used to separate lines of text.", "The code 12710 (DEL) is also a control character.", "Extended ASCII sets defined by ISO 8859 added the codes 12810 through 15910 as control characters.", "This was primarily done so that if the high bit was stripped, it would not change a printing character to a C0 control code.", "This second set is called the C1 set.These 65 control codes were carried over to Unicode.", "Unicode added more characters that could be considered controls, but it makes a distinction between these \"Formatting characters\" (such as the zero-width non-joiner) and the 65 control characters.The Extended Binary Coded Decimal Interchange Code (EBCDIC) character set contains 65 control codes, including all of the ASCII control codes plus additional codes which are mostly used to control IBM peripherals.+ ASCII control codes.", "0x00 0x10 0x00 NUL DLE 0x01 SOH DC1 0x02 STX DC2 0x03 ETX DC3 0x04 EOT DC4 0x05 ENQ NAK 0x06 ACK SYN 0x07 BEL ETB 0x08 BS CAN 0x09 HT EM 0x0A LF SUB 0x0B VT ESC 0x0C FF FS 0x0D CR GS 0x0E SO RS 0x0F SI US 0x7F DELThe control characters in ASCII still in common use include:* 0x00 (null, , , ), originally intended to be an ignored character, but now used by many programming languages including C to mark the end of a string.", "* 0x07 (bell, , , ), which may cause the device to emit a warning such as a bell or beep sound or the screen flashing.", "* 0x08 (backspace, , , ), may overprint the previous character.", "* 0x09 (horizontal tab, , , ), moves the printing position right to the next tab stop.", "* 0x0A (line feed, , , ), moves the print head down one line, or to the left edge and down.", "Used as the end of line marker in most UNIX systems and variants.", "* 0x0B (vertical tab, , , ), vertical tabulation.", "* 0x0C (form feed, , , ), to cause a printer to eject paper to the top of the next page, or a video terminal to clear the screen.", "* 0x0D (carriage return, , , ), moves the printing position to the start of the line, allowing overprinting.", "Used as the end of line marker in Classic Mac OS, OS-9, FLEX (and variants).", "A pair is used by CP/M-80 and its derivatives including DOS and Windows, and by Application Layer protocols such as FTP, SMTP, and HTTP.", "* 0x1A (Control-Z, , ).", "Acts as an end-of-file for the Windows text-mode file i/o.", "* 0x1B (escape, , (GCC only), ).", "Introduces an escape sequence.Control characters may be described as doing something when the user inputs them, such as code 3 (End-of-Text character, ETX, ) to interrupt the running process, or code 4 (End-of-Transmission character, EOT, ), used to end text input on Unix or to exit a Unix shell.", "These uses usually have little to do with their use when they are in text being output." ], [ "In Unicode", "In Unicode, \"Control-characters\" are U+0000—U+001F (C0 controls), U+007F (delete), and U+0080—U+009F (C1 controls).", "Their General Category is \"Cc\".", "Formatting codes are distinct, in General Category \"Cf\".", "The Cc control characters have no Name in Unicode, but are given labels such as \"\" instead." ], [ "Display", "There are a number of techniques to display non-printing characters, which may be illustrated with the bell character in ASCII encoding:* Code point: decimal 7, hexadecimal 0x07* An abbreviation, often three capital letters: BEL* A special character condensing the abbreviation: Unicode U+2407 (␇), \"symbol for bell\"* An ISO 2047 graphical representation: Unicode U+237E (⍾), \"graphic for bell\"* Caret notation in ASCII, where code point 00xxxxx is represented as a caret followed by the capital letter at code point 10xxxxx: ^G* An escape sequence, as in C/C++ character string codes: , , , etc." ], [ "How control characters map to keyboards", "ASCII-based keyboards have a key labelled \"Control\", \"Ctrl\", or (rarely) \"Cntl\" which is used much like a shift key, being pressed in combination with another letter or symbol key.", "In one implementation, the control key generates the code 64 places below the code for the (generally) uppercase letter it is pressed in combination with (i.e., subtract 0x40 from ASCII code value of the (generally) uppercase letter).", "The other implementation is to take the ASCII code produced by the key and bitwise AND it with 0x1F, forcing bits 5 to 7 to zero.", "For example, pressing \"control\" and the letter \"g\" (which is 0110 0111 in binary), produces the code 7 (BELL, 7 in base ten, or 0000 0111 in binary).", "The NULL character (code 0) is represented by Ctrl-@, \"@\" being the code immediately before \"A\" in the ASCII character set.", "For convenience, some terminals accept Ctrl-Space as an alias for Ctrl-@.", "In either case, this produces one of the 32 ASCII control codes between 0 and 31.Neither approach works to produce the DEL character because of its special location in the table and its value (code 12710), Ctrl-?", "is sometimes used for this character.When the control key is held down, letter keys produce the same control characters regardless of the state of the shift or caps lock keys.", "In other words, it does not matter whether the key would have produced an upper-case or a lower-case letter.", "The interpretation of the control key with the space, graphics character, and digit keys (ASCII codes 32 to 63) vary between systems.", "Some will produce the same character code as if the control key were not held down.", "Other systems translate these keys into control characters when the control key is held down.", "The interpretation of the control key with non-ASCII (\"foreign\") keys also varies between systems.Control characters are often rendered into a printable form known as caret notation by printing a caret (^) and then the ASCII character that has a value of the control character plus 64.Control characters generated using letter keys are thus displayed with the upper-case form of the letter.", "For example, ^G represents code 7, which is generated by pressing the G key when the control key is held down.Keyboards also typically have a few single keys which produce control character codes.", "For example, the key labelled \"Backspace\" typically produces code 8, \"Tab\" code 9, \"Enter\" or \"Return\" code 13 (though some keyboards might produce code 10 for \"Enter\").Many keyboards include keys that do not correspond to any ASCII printable or control character, for example cursor control arrows and word processing functions.", "The associated keypresses are communicated to computer programs by one of four methods: appropriating otherwise unused control characters; using some encoding other than ASCII; using multi-character control sequences; or using an additional mechanism outside of generating characters.", "\"Dumb\" computer terminals typically use control sequences.", "Keyboards attached to stand-alone personal computers made in the 1980s typically use one (or both) of the first two methods.", "Modern computer keyboards generate scancodes that identify the specific physical keys that are pressed; computer software then determines how to handle the keys that are pressed, including any of the four methods described above." ], [ "The design purpose", "The control characters were designed to fall into a few groups: printing and display control, data structuring, transmission control, and miscellaneous.===Printing and display control===Printing control characters were first used to control the physical mechanism of printers, the earliest output device.", "An early example of this idea was the use of Figures (FIGS) and Letters (LTRS) in Baudot code to shift between two code pages.", "A later, but still early, example was the out-of-band ASA carriage control characters.", "Later, control characters were integrated into the stream of data to be printed.The carriage return character (CR), when sent to such a device, causes it to put the character at the edge of the paper at which writing begins (it may, or may not, also move the printing position to the next line).The line feed character (LF/NL) causes the device to put the printing position on the next line.", "It may (or may not), depending on the device and its configuration, also move the printing position to the start of the next line (which would be the leftmost position for left-to-right scripts, such as the alphabets used for Western languages, and the rightmost position for right-to-left scripts such as the Hebrew and Arabic alphabets).The vertical and horizontal tab characters (VT and HT/TAB) cause the output device to move the printing position to the next tab stop in the direction of reading.The form feed character (FF/NP) starts a new sheet of paper, and may or may not move to the start of the first line.The backspace character (BS) moves the printing position one character space backwards.", "On printers, including hard-copy terminals, this is most often used so the printer can overprint characters to make other, not normally available, characters.", "On video terminals and other electronic output devices, there are often software (or hardware) configuration choices that allow a destructive backspace (e.g., a BS, SP, BS sequence), which erases, or a non-destructive one, which does not.The shift in and shift out characters (SI and SO) selected alternate character sets, fonts, underlining, or other printing modes.", "Escape sequences were often used to do the same thing.With the advent of computer terminals that did not physically print on paper and so offered more flexibility regarding screen placement, erasure, and so forth, printing control codes were adapted.", "Form feeds, for example, usually cleared the screen, there being no new paper page to move to.", "More complex escape sequences were developed to take advantage of the flexibility of the new terminals, and indeed of newer printers.", "The concept of a control character had always been somewhat limiting, and was extremely so when used with new, much more flexible, hardware.", "Control sequences (sometimes implemented as escape sequences) could match the new flexibility and power and became the standard method.", "However, there were, and remain, a large variety of standard sequences to choose from.===Data structuring===The separators (File, Group, Record, and Unit: FS, GS, RS and US) were made to structure data, usually on a tape, in order to simulate punched cards.End of medium (EM) warns that the tape (or other recording medium) is ending.While many systems use CR/LF and TAB for structuring data, it is possible to encounter the separator control characters in data that needs to be structured.", "The separator control characters are not overloaded; there is no general use of them except to separate data into structured groupings.", "Their numeric values are contiguous with the space character, which can be considered a member of the group, as a word separator.For example, the RS separator is used by (JSON Text Sequences) to encode a sequence of JSON elements.", "Each sequence item starts with a RS character and ends with a line feed.", "This allows to serialize open-ended JSON sequences.", "It is one of the JSON streaming protocols.===Transmission control===The transmission control characters were intended to structure a data stream, and to manage re-transmission or graceful failure, as needed, in the face of transmission errors.The start of heading (SOH) character was to mark a non-data section of a data stream—the part of a stream containing addresses and other housekeeping data.", "The start of text character (STX) marked the end of the header, and the start of the textual part of a stream.", "The end of text character (ETX) marked the end of the data of a message.", "A widely used convention is to make the two characters preceding ETX a checksum or CRC for error-detection purposes.", "The end of transmission block character (ETB) was used to indicate the end of a block of data, where data was divided into such blocks for transmission purposes.The escape character (ESC) was intended to \"quote\" the next character, if it was another control character it would print it instead of performing the control function.", "It is almost never used for this purpose today.", "Various printable characters are used as visible \"escape characters\", depending on context.The substitute character (SUB) was intended to request a translation of the next character from a printable character to another value, usually by setting bit 5 to zero.", "This is handy because some media (such as sheets of paper produced by typewriters) can transmit only printable characters.", "However, on MS-DOS systems with files opened in text mode, \"end of text\" or \"end of file\" is marked by this Ctrl-Z character, instead of the Ctrl-C or Ctrl-D, which are common on other operating systems.The cancel character (CAN) signaled that the previous element should be discarded.", "The negative acknowledge character (NAK) is a definite flag for, usually, noting that reception was a problem, and, often, that the current element should be sent again.", "The acknowledge character (ACK) is normally used as a flag to indicate no problem detected with current element.When a transmission medium is half duplex (that is, it can transmit in only one direction at a time), there is usually a master station that can transmit at any time, and one or more slave stations that transmit when they have permission.", "The enquire character (ENQ) is generally used by a master station to ask a slave station to send its next message.", "A slave station indicates that it has completed its transmission by sending the end of transmission character (EOT).The device control codes (DC1 to DC4) were originally generic, to be implemented as necessary by each device.", "However, a universal need in data transmission is to request the sender to stop transmitting when a receiver is temporarily unable to accept any more data.", "Digital Equipment Corporation invented a convention which used 19 (the device control 3 character (DC3), also known as control-S, or XOFF) to \"S\"top transmission, and 17 (the device control 1 character (DC1), a.k.a.", "control-Q, or XON) to start transmission.", "It has become so widely used that most don't realize it is not part of official ASCII.", "This technique, however implemented, avoids additional wires in the data cable devoted only to transmission management, which saves money.", "A sensible protocol for the use of such transmission flow control signals must be used, to avoid potential deadlock conditions, however.The data link escape character (DLE) was intended to be a signal to the other end of a data link that the following character is a control character such as STX or ETX.", "For example a packet may be structured in the following way (DLE) (DLE) .===Miscellaneous codes===Code 7 (BEL) is intended to cause an audible signal in the receiving terminal.Many of the ASCII control characters were designed for devices of the time that are not often seen today.", "For example, code 22, \"synchronous idle\" (SYN), was originally sent by synchronous modems (which have to send data constantly) when there was no actual data to send.", "(Modern systems typically use a start bit to announce the beginning of a transmitted word— this is a feature of ''asynchronous'' communication.", "''Synchronous'' communication links were more often seen with mainframes, where they were typically run over corporate leased lines to connect a mainframe to another mainframe or perhaps a minicomputer.", ")Code 0 (ASCII code name NUL) is a special case.", "In paper tape, it is the case when there are no holes.", "It is convenient to treat this as a ''fill'' character with no meaning otherwise.", "Since the position of a NUL character has no holes punched, it can be replaced with any other character at a later time, so it was typically used to reserve space, either for correcting errors or for inserting information that would be available at a later time or in another place.", "In computing, it is often used for padding in fixed length records; to mark the end of a string; and formerly to give printing devices enough time to execute a control function.Code 127 (DEL, a.k.a.", "\"rubout\") is likewise a special case.", "Its 7-bit code is ''all-bits-on'' in binary, which essentially erased a character cell on a paper tape when overpunched.", "Paper tape was a common storage medium when ASCII was developed, with a computing history dating back to WWII code breaking equipment at Biuro Szyfrów.", "Paper tape became obsolete in the 1970s, so this clever aspect of ASCII rarely saw any use after that.", "Some systems (such as the original Apples) converted it to a backspace.", "But because its code is in the range occupied by other printable characters, and because it had no official assigned glyph, many computer equipment vendors used it as an additional printable character (often an all-black \"box\" character useful for erasing text by overprinting with ink).Non-erasable programmable ROMs are typically implemented as arrays of fusible elements, each representing a bit, which can only be switched one way, usually from one to zero.", "In such PROMs, the DEL and NUL characters can be used in the same way that they were used on punched tape: one to reserve meaningless fill bytes that can be written later, and the other to convert written bytes to meaningless fill bytes.", "For PROMs that switch one to zero, the roles of NUL and DEL are reversed; also, DEL will only work with 7-bit characters, which are rarely used today; for 8-bit content, the character code 255, commonly defined as a nonbreaking space character, can be used instead of DEL.Many file systems do not allow control characters in filenames, as they may have reserved functions." ], [ "See also", "* , HJKL as arrow keys, used on ADM-3A terminal* C0 and C1 control codes* Escape sequence* In-band signaling* Whitespace character" ], [ "Notes and references" ], [ "External links", "* ISO IR 1 C0 Set of ISO 646 (PDF)" ] ]

[ [ "Carbon" ], [ "Introduction", "'''Carbon''' () is a chemical element; it has symbol '''C''' and atomic number 6.It is nonmetallic and tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 electrons.", "It belongs to group 14 of the periodic table.", "Carbon makes up about 0.025 percent of Earth's crust.", "Three isotopes occur naturally, C and C being stable, while C is a radionuclide, decaying with a half-life of about 5,730 years.", "Carbon is one of the few elements known since antiquity.Carbon is the 15th most abundant element in the Earth's crust, and the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen.", "Carbon's abundance, its unique diversity of organic compounds, and its unusual ability to form polymers at the temperatures commonly encountered on Earth, enables this element to serve as a common element of all known life.", "It is the second most abundant element in the human body by mass (about 18.5%) after oxygen.The atoms of carbon can bond together in diverse ways, resulting in various allotropes of carbon.", "Well-known allotropes include graphite, diamond, amorphous carbon, and fullerenes.", "The physical properties of carbon vary widely with the allotropic form.", "For example, graphite is opaque and black, while diamond is highly transparent.", "Graphite is soft enough to form a streak on paper (hence its name, from the Greek verb \"γράφειν\" which means \"to write\"), while diamond is the hardest naturally occurring material known.", "Graphite is a good electrical conductor while diamond has a low electrical conductivity.", "Under normal conditions, diamond, carbon nanotubes, and graphene have the highest thermal conductivities of all known materials.", "All carbon allotropes are solids under normal conditions, with graphite being the most thermodynamically stable form at standard temperature and pressure.", "They are chemically resistant and require high temperature to react even with oxygen.The most common oxidation state of carbon in inorganic compounds is +4, while +2 is found in carbon monoxide and transition metal carbonyl complexes.", "The largest sources of inorganic carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil, and methane clathrates.", "Carbon forms a vast number of compounds, with about two hundred million having been described and indexed; and yet that number is but a fraction of the number of theoretically possible compounds under standard conditions." ], [ "Characteristics", "Theoretically predicted phase diagram of carbon, from 1989.Newer work indicates that the melting point of diamond (top-right curve) does not go above about 9000 K.The allotropes of carbon include graphite, one of the softest known substances, and diamond, the hardest naturally occurring substance.", "It bonds readily with other small atoms, including other carbon atoms, and is capable of forming multiple stable covalent bonds with suitable multivalent atoms.", "Carbon is a component element in the large majority of all chemical compounds, with about two hundred million examples having been described in the published chemical literature.", "Carbon also has the highest sublimation point of all elements.", "At atmospheric pressure it has no melting point, as its triple point is at and , so it sublimes at about .", "Graphite is much more reactive than diamond at standard conditions, despite being more thermodynamically stable, as its delocalised pi system is much more vulnerable to attack.", "For example, graphite can be oxidised by hot concentrated nitric acid at standard conditions to mellitic acid, C6(CO2H)6, which preserves the hexagonal units of graphite while breaking up the larger structure.Carbon sublimes in a carbon arc, which has a temperature of about 5800 K (5,530 °C or 9,980 °F).", "Thus, irrespective of its allotropic form, carbon remains solid at higher temperatures than the highest-melting-point metals such as tungsten or rhenium.", "Although thermodynamically prone to oxidation, carbon resists oxidation more effectively than elements such as iron and copper, which are weaker reducing agents at room temperature.Carbon is the sixth element, with a ground-state electron configuration of 1s22s22p2, of which the four outer electrons are valence electrons.", "Its first four ionisation energies, 1086.5, 2352.6, 4620.5 and 6222.7 kJ/mol, are much higher than those of the heavier group-14 elements.", "The electronegativity of carbon is 2.5, significantly higher than the heavier group-14 elements (1.8–1.9), but close to most of the nearby nonmetals, as well as some of the second- and third-row transition metals.", "Carbon's covalent radii are normally taken as 77.2 pm (C−C), 66.7 pm (C=C) and 60.3 pm (C≡C), although these may vary depending on coordination number and what the carbon is bonded to.", "In general, covalent radius decreases with lower coordination number and higher bond order.Carbon-based compounds form the basis of all known life on Earth, and the carbon-nitrogen-oxygen cycle provides a small portion of the energy produced by the Sun, and most of the energy in larger stars (e.g.", "Sirius).", "Although it forms an extraordinary variety of compounds, most forms of carbon are comparatively unreactive under normal conditions.", "At standard temperature and pressure, it resists all but the strongest oxidizers.", "It does not react with sulfuric acid, hydrochloric acid, chlorine or any alkalis.", "At elevated temperatures, carbon reacts with oxygen to form carbon oxides and will rob oxygen from metal oxides to leave the elemental metal.", "This exothermic reaction is used in the iron and steel industry to smelt iron and to control the carbon content of steel:: + 4 C + 2 → 3 Fe + 4 .Carbon reacts with sulfur to form carbon disulfide, and it reacts with steam in the coal-gas reaction used in coal gasification::C + HO → CO + H.Carbon combines with some metals at high temperatures to form metallic carbides, such as the iron carbide cementite in steel and tungsten carbide, widely used as an abrasive and for making hard tips for cutting tools.The system of carbon allotropes spans a range of extremes:Graphite is one of the softest materials known.Synthetic nanocrystalline diamond is the hardest material known.Graphite is a very good lubricant, displaying superlubricity.Diamond is the ultimate abrasive.Graphite is a conductor of electricity.Diamond is an excellent electrical insulator, and has the highest breakdown electric field of any known material.Some forms of graphite are used for thermal insulation (i.e.", "firebreaks and heat shields), but some other forms are good thermal conductors.Diamond is the best known naturally occurring thermal conductor.Graphite is opaque.Diamond is highly transparent.Graphite crystallizes in the hexagonal system.Diamond crystallizes in the cubic system.Amorphous carbon is completely isotropic.Carbon nanotubes are among the most anisotropic materials known.===Allotropes===Atomic carbon is a very short-lived species and, therefore, carbon is stabilized in various multi-atomic structures with diverse molecular configurations called allotropes.", "The three relatively well-known allotropes of carbon are amorphous carbon, graphite, and diamond.", "Once considered exotic, fullerenes are nowadays commonly synthesized and used in research; they include buckyballs, carbon nanotubes, carbon nanobuds and nanofibers.", "Several other exotic allotropes have also been discovered, such as lonsdaleite, glassy carbon, carbon nanofoam and linear acetylenic carbon (carbyne).Graphene is a two-dimensional sheet of carbon with the atoms arranged in a hexagonal lattice.", "As of 2009, graphene appears to be the strongest material ever tested.", "The process of separating it from graphite will require some further technological development before it is economical for industrial processes.", "If successful, graphene could be used in the construction of a space elevator.", "It could also be used to safely store hydrogen for use in a hydrogen based engine in cars.A large sample of glassy carbon The amorphous form is an assortment of carbon atoms in a non-crystalline, irregular, glassy state, not held in a crystalline macrostructure.", "It is present as a powder, and is the main constituent of substances such as charcoal, lampblack (soot), and activated carbon.", "At normal pressures, carbon takes the form of graphite, in which each atom is bonded trigonally to three others in a plane composed of fused hexagonal rings, just like those in aromatic hydrocarbons.", "The resulting network is 2-dimensional, and the resulting flat sheets are stacked and loosely bonded through weak van der Waals forces.", "This gives graphite its softness and its cleaving properties (the sheets slip easily past one another).", "Because of the delocalization of one of the outer electrons of each atom to form a π-cloud, graphite conducts electricity, but only in the plane of each covalently bonded sheet.", "This results in a lower bulk electrical conductivity for carbon than for most metals.", "The delocalization also accounts for the energetic stability of graphite over diamond at room temperature.Some allotropes of carbon: a) diamond; b) graphite; c) lonsdaleite; d–f) fullerenes (C, C, C); g) amorphous carbon; h) carbon nanotubeAt very high pressures, carbon forms the more compact allotrope, diamond, having nearly twice the density of graphite.", "Here, each atom is bonded tetrahedrally to four others, forming a 3-dimensional network of puckered six-membered rings of atoms.", "Diamond has the same cubic structure as silicon and germanium, and because of the strength of the carbon-carbon bonds, it is the hardest naturally occurring substance measured by resistance to scratching.", "Contrary to the popular belief that ''\"diamonds are forever\"'', they are thermodynamically unstable (Δf''G''°(diamond, 298 K) = 2.9 kJ/mol) under normal conditions (298 K, 105 Pa) and should theoretically transform into graphite.", "But due to a high activation energy barrier, the transition into graphite is so slow at normal temperature that it is unnoticeable.", "However, at very high temperatures diamond will turn into graphite, and diamonds can burn up in a house fire.", "The bottom left corner of the phase diagram for carbon has not been scrutinized experimentally.", "Although a computational study employing density functional theory methods reached the conclusion that as and , diamond becomes more stable than graphite by approximately 1.1 kJ/mol, more recent and definitive experimental and computational studies show that graphite is more stable than diamond for , without applied pressure, by 2.7 kJ/mol at ''T'' = 0 K and 3.2 kJ/mol at ''T'' = 298.15 K. Under some conditions, carbon crystallizes as lonsdaleite, a hexagonal crystal lattice with all atoms covalently bonded and properties similar to those of diamond.Fullerenes are a synthetic crystalline formation with a graphite-like structure, but in place of flat hexagonal cells only, some of the cells of which fullerenes are formed may be pentagons, nonplanar hexagons, or even heptagons of carbon atoms.", "The sheets are thus warped into spheres, ellipses, or cylinders.", "The properties of fullerenes (split into buckyballs, buckytubes, and nanobuds) have not yet been fully analyzed and represent an intense area of research in nanomaterials.", "The names ''fullerene'' and ''buckyball'' are given after Richard Buckminster Fuller, popularizer of geodesic domes, which resemble the structure of fullerenes.", "The buckyballs are fairly large molecules formed completely of carbon bonded trigonally, forming spheroids (the best-known and simplest is the soccerball-shaped C buckminsterfullerene).", "Carbon nanotubes (buckytubes) are structurally similar to buckyballs, except that each atom is bonded trigonally in a curved sheet that forms a hollow cylinder.", "Nanobuds were first reported in 2007 and are hybrid buckytube/buckyball materials (buckyballs are covalently bonded to the outer wall of a nanotube) that combine the properties of both in a single structure.Comet C/2014 Q2 (Lovejoy) surrounded by glowing carbon vaporOf the other discovered allotropes, carbon nanofoam is a ferromagnetic allotrope discovered in 1997.It consists of a low-density cluster-assembly of carbon atoms strung together in a loose three-dimensional web, in which the atoms are bonded trigonally in six- and seven-membered rings.", "It is among the lightest known solids, with a density of about 2 kg/m.", "Similarly, glassy carbon contains a high proportion of closed porosity, but contrary to normal graphite, the graphitic layers are not stacked like pages in a book, but have a more random arrangement.", "Linear acetylenic carbon has the chemical structure −(C≡C)− .", "Carbon in this modification is linear with ''sp'' orbital hybridization, and is a polymer with alternating single and triple bonds.", "This carbyne is of considerable interest to nanotechnology as its Young's modulus is 40 times that of the hardest known material – diamond.In 2015, a team at the North Carolina State University announced the development of another allotrope they have dubbed Q-carbon, created by a high-energy low-duration laser pulse on amorphous carbon dust.", "Q-carbon is reported to exhibit ferromagnetism, fluorescence, and a hardness superior to diamonds.In the vapor phase, some of the carbon is in the form of highly reactive diatomic carbon dicarbon ().", "When excited, this gas glows green.===Occurrence===Graphite ore, shown with a penny for scaleRaw diamond crystal\"Present day\" (1990s) sea surface dissolved inorganic carbon concentration (from the GLODAP climatology)Carbon is the fourth most abundant chemical element in the observable universe by mass after hydrogen, helium, and oxygen.", "Carbon is abundant in the Sun, stars, comets, and in the atmospheres of most planets.", "Some meteorites contain microscopic diamonds that were formed when the Solar System was still a protoplanetary disk.", "Microscopic diamonds may also be formed by the intense pressure and high temperature at the sites of meteorite impacts.In 2014 NASA announced a greatly upgraded database for tracking polycyclic aromatic hydrocarbons (PAHs) in the universe.", "More than 20% of the carbon in the universe may be associated with PAHs, complex compounds of carbon and hydrogen without oxygen.", "These compounds figure in the PAH world hypothesis where they are hypothesized to have a role in abiogenesis and formation of life.", "PAHs seem to have been formed \"a couple of billion years\" after the Big Bang, are widespread throughout the universe, and are associated with new stars and exoplanets.It has been estimated that the solid earth as a whole contains 730 ppm of carbon, with 2000 ppm in the core and 120 ppm in the combined mantle and crust.", "Since the mass of the earth is , this would imply 4360 million gigatonnes of carbon.", "This is much more than the amount of carbon in the oceans or atmosphere (below).In combination with oxygen in carbon dioxide, carbon is found in the Earth's atmosphere (approximately 900 gigatonnes of carbon — each ppm corresponds to 2.13 Gt) and dissolved in all water bodies (approximately 36,000 gigatonnes of carbon).", "Carbon in the biosphere has been estimated at 550 gigatonnes but with a large uncertainty, due mostly to a huge uncertainty in the amount of terrestrial deep subsurface bacteria.", "Hydrocarbons (such as coal, petroleum, and natural gas) contain carbon as well.", "Coal \"reserves\" (not \"resources\") amount to around 900 gigatonnes with perhaps 18,000 Gt of resources.", "Oil reserves are around 150 gigatonnes.", "Proven sources of natural gas are about (containing about 105 gigatonnes of carbon), but studies estimate another of \"unconventional\" deposits such as shale gas, representing about 540 gigatonnes of carbon.Carbon is also found in methane hydrates in polar regions and under the seas.", "Various estimates put this carbon between 500, 2500, or 3,000 Gt.According to one source, in the period from 1751 to 2008 about 347 gigatonnes of carbon were released as carbon dioxide to the atmosphere from burning of fossil fuels.", "Another source puts the amount added to the atmosphere for the period since 1750 at 879 Gt, and the total going to the atmosphere, sea, and land (such as peat bogs) at almost 2,000 Gt.Carbon is a constituent (about 12% by mass) of the very large masses of carbonate rock (limestone, dolomite, marble, and others).", "Coal is very rich in carbon (anthracite contains 92–98%) and is the largest commercial source of mineral carbon, accounting for 4,000 gigatonnes or 80% of fossil fuel.As for individual carbon allotropes, graphite is found in large quantities in the United States (mostly in New York and Texas), Russia, Mexico, Greenland, and India.", "Natural diamonds occur in the rock kimberlite, found in ancient volcanic \"necks\", or \"pipes\".", "Most diamond deposits are in Africa, notably in South Africa, Namibia, Botswana, the Republic of the Congo, and Sierra Leone.", "Diamond deposits have also been found in Arkansas, Canada, the Russian Arctic, Brazil, and in Northern and Western Australia.", "Diamonds are now also being recovered from the ocean floor off the Cape of Good Hope.", "Diamonds are found naturally, but about 30% of all industrial diamonds used in the U.S. are now manufactured.Carbon-14 is formed in upper layers of the troposphere and the stratosphere at altitudes of 9–15 km by a reaction that is precipitated by cosmic rays.", "Thermal neutrons are produced that collide with the nuclei of nitrogen-14, forming carbon-14 and a proton.", "As such, of atmospheric carbon dioxide contains carbon-14.Carbon-rich asteroids are relatively preponderant in the outer parts of the asteroid belt in the Solar System.", "These asteroids have not yet been directly sampled by scientists.", "The asteroids can be used in hypothetical space-based carbon mining, which may be possible in the future, but is currently technologically impossible.===Isotopes===Isotopes of carbon are atomic nuclei that contain six protons plus a number of neutrons (varying from 2 to 16).", "Carbon has two stable, naturally occurring isotopes.", "The isotope carbon-12 (C) forms 98.93% of the carbon on Earth, while carbon-13 (C) forms the remaining 1.07%.", "The concentration of C is further increased in biological materials because biochemical reactions discriminate against C. In 1961, the International Union of Pure and Applied Chemistry (IUPAC) adopted the isotope carbon-12 as the basis for atomic weights.", "Identification of carbon in nuclear magnetic resonance (NMR) experiments is done with the isotope C.Carbon-14 (C) is a naturally occurring radioisotope, created in the upper atmosphere (lower stratosphere and upper troposphere) by interaction of nitrogen with cosmic rays.", "It is found in trace amounts on Earth of 1 part per trillion (0.0000000001%) or more, mostly confined to the atmosphere and superficial deposits, particularly of peat and other organic materials.", "This isotope decays by 0.158 MeV β emission.", "Because of its relatively short half-life of 5730 years, C is virtually absent in ancient rocks.", "The amount of C in the atmosphere and in living organisms is almost constant, but decreases predictably in their bodies after death.", "This principle is used in radiocarbon dating, invented in 1949, which has been used extensively to determine the age of carbonaceous materials with ages up to about 40,000 years.There are 15 known isotopes of carbon and the shortest-lived of these is C which decays through proton emission and alpha decay and has a half-life of 1.98739 × 10 s. The exotic C exhibits a nuclear halo, which means its radius is appreciably larger than would be expected if the nucleus were a sphere of constant density.===Formation in stars===Formation of the carbon atomic nucleus occurs within a giant or supergiant star through the triple-alpha process.", "This requires a nearly simultaneous collision of three alpha particles (helium nuclei), as the products of further nuclear fusion reactions of helium with hydrogen or another helium nucleus produce lithium-5 and beryllium-8 respectively, both of which are highly unstable and decay almost instantly back into smaller nuclei.", "The triple-alpha process happens in conditions of temperatures over 100 megakelvins and helium concentration that the rapid expansion and cooling of the early universe prohibited, and therefore no significant carbon was created during the Big Bang.According to current physical cosmology theory, carbon is formed in the interiors of stars on the horizontal branch.", "When massive stars die as supernova, the carbon is scattered into space as dust.", "This dust becomes component material for the formation of the next-generation star systems with accreted planets.", "The Solar System is one such star system with an abundance of carbon, enabling the existence of life as we know it.", "It is the opinion of most scholars that all the carbon in the Solar System and the Milky Way comes from dying stars.The CNO cycle is an additional hydrogen fusion mechanism that powers stars, wherein carbon operates as a catalyst.Rotational transitions of various isotopic forms of carbon monoxide (for example, CO, CO, and CO) are detectable in the submillimeter wavelength range, and are used in the study of newly forming stars in molecular clouds.===Carbon cycle===Diagram of the carbon cycle.", "The black numbers indicate how much carbon is stored in various reservoirs, in billions tonnes (\"GtC\" stands for gigatonnes of carbon; figures are ).", "The purple numbers indicate how much carbon moves between reservoirs each year.", "The sediments, as defined in this diagram, do not include the ≈70 million GtC of carbonate rock and kerogen.Under terrestrial conditions, conversion of one element to another is very rare.", "Therefore, the amount of carbon on Earth is effectively constant.", "Thus, processes that use carbon must obtain it from somewhere and dispose of it somewhere else.", "The paths of carbon in the environment form the carbon cycle.", "For example, photosynthetic plants draw carbon dioxide from the atmosphere (or seawater) and build it into biomass, as in the Calvin cycle, a process of carbon fixation.", "Some of this biomass is eaten by animals, while some carbon is exhaled by animals as carbon dioxide.", "The carbon cycle is considerably more complicated than this short loop; for example, some carbon dioxide is dissolved in the oceans; if bacteria do not consume it, dead plant or animal matter may become petroleum or coal, which releases carbon when burned." ], [ "Compounds", "===Organic compounds===Structural formula of methane, the simplest possible organic compound.Correlation between the ''carbon cycle'' and formation of organic compounds.", "In plants, carbon dioxide formed by carbon fixation can join with water in photosynthesis (green) to form organic compounds, which can be used and further converted by both plants and animals.Carbon can form very long chains of interconnecting carbon–carbon bonds, a property that is called catenation.", "Carbon-carbon bonds are strong and stable.", "Through catenation, carbon forms a countless number of compounds.", "A tally of unique compounds shows that more contain carbon than do not.", "A similar claim can be made for hydrogen because most organic compounds contain hydrogen chemically bonded to carbon or another common element like oxygen or nitrogen.The simplest form of an organic molecule is the hydrocarbon—a large family of organic molecules that are composed of hydrogen atoms bonded to a chain of carbon atoms.", "A hydrocarbon backbone can be substituted by other atoms, known as heteroatoms.", "Common heteroatoms that appear in organic compounds include oxygen, nitrogen, sulfur, phosphorus, and the nonradioactive halogens, as well as the metals lithium and magnesium.", "Organic compounds containing bonds to metal are known as organometallic compounds (''see below'').", "Certain groupings of atoms, often including heteroatoms, recur in large numbers of organic compounds.", "These collections, known as ''functional groups'', confer common reactivity patterns and allow for the systematic study and categorization of organic compounds.", "Chain length, shape and functional groups all affect the properties of organic molecules.In most stable compounds of carbon (and nearly all stable ''organic'' compounds), carbon obeys the octet rule and is ''tetravalent'', meaning that a carbon atom forms a total of four covalent bonds (which may include double and triple bonds).", "Exceptions include a small number of stabilized ''carbocations'' (three bonds, positive charge), ''radicals'' (three bonds, neutral), ''carbanions'' (three bonds, negative charge) and ''carbenes'' (two bonds, neutral), although these species are much more likely to be encountered as unstable, reactive intermediates.Carbon occurs in all known organic life and is the basis of organic chemistry.", "When united with hydrogen, it forms various hydrocarbons that are important to industry as refrigerants, lubricants, solvents, as chemical feedstock for the manufacture of plastics and petrochemicals, and as fossil fuels.When combined with oxygen and hydrogen, carbon can form many groups of important biological compounds including sugars, lignans, chitins, alcohols, fats, aromatic esters, carotenoids and terpenes.", "With nitrogen it forms alkaloids, and with the addition of sulfur also it forms antibiotics, amino acids, and rubber products.", "With the addition of phosphorus to these other elements, it forms DNA and RNA, the chemical-code carriers of life, and adenosine triphosphate (ATP), the most important energy-transfer molecule in all living cells.", "Norman Horowitz, head of the Mariner and Viking missions to Mars (1965-1976), considered that the unique characteristics of carbon made it unlikely that any other element could replace carbon, even on another planet, to generate the biochemistry necessary for life.===Inorganic compounds===Commonly carbon-containing compounds which are associated with minerals or which do not contain bonds to the other carbon atoms, halogens, or hydrogen, are treated separately from classical organic compounds; the definition is not rigid, and the classification of some compounds can vary from author to author (see reference articles above).", "Among these are the simple oxides of carbon.", "The most prominent oxide is carbon dioxide ().", "This was once the principal constituent of the paleoatmosphere, but is a minor component of the Earth's atmosphere today.", "Dissolved in water, it forms carbonic acid (), but as most compounds with multiple single-bonded oxygens on a single carbon it is unstable.", "Through this intermediate, though, resonance-stabilized carbonate ions are produced.", "Some important minerals are carbonates, notably calcite.", "Carbon disulfide () is similar.", "Nevertheless, due to its physical properties and its association with organic synthesis, carbon disulfide is sometimes classified as an ''organic'' solvent.The other common oxide is carbon monoxide (CO).", "It is formed by incomplete combustion, and is a colorless, odorless gas.", "The molecules each contain a triple bond and are fairly polar, resulting in a tendency to bind permanently to hemoglobin molecules, displacing oxygen, which has a lower binding affinity.", "Cyanide (CN), has a similar structure, but behaves much like a halide ion (pseudohalogen).", "For example, it can form the nitride cyanogen molecule ((CN)), similar to diatomic halides.", "Likewise, the heavier analog of cyanide, cyaphide (CP), is also considered inorganic, though most simple derivatives are highly unstable.", "Other uncommon oxides are carbon suboxide (), the unstable dicarbon monoxide (CO), carbon trioxide (CO), cyclopentanepentone (CO), cyclohexanehexone (CO), and mellitic anhydride (CO).", "However, mellitic anhydride is the triple acyl anhydride of mellitic acid; moreover, it contains a benzene ring.", "Thus, many chemists consider it to be organic.With reactive metals, such as tungsten, carbon forms either carbides (C) or acetylides () to form alloys with high melting points.", "These anions are also associated with methane and acetylene, both very weak acids.", "With an electronegativity of 2.5, carbon prefers to form covalent bonds.", "A few carbides are covalent lattices, like carborundum (SiC), which resembles diamond.", "Nevertheless, even the most polar and salt-like of carbides are not completely ionic compounds.===Organometallic compounds===Organometallic compounds by definition contain at least one carbon-metal covalent bond.", "A wide range of such compounds exist; major classes include simple alkyl-metal compounds (for example, tetraethyllead), η-alkene compounds (for example, Zeise's salt), and η-allyl compounds (for example, allylpalladium chloride dimer); metallocenes containing cyclopentadienyl ligands (for example, ferrocene); and transition metal carbene complexes.", "Many metal carbonyls and metal cyanides exist (for example, tetracarbonylnickel and potassium ferricyanide); some workers consider metal carbonyl and cyanide complexes without other carbon ligands to be purely inorganic, and not organometallic.", "However, most organometallic chemists consider metal complexes with any carbon ligand, even 'inorganic carbon' (e.g., carbonyls, cyanides, and certain types of carbides and acetylides) to be organometallic in nature.", "Metal complexes containing organic ligands without a carbon-metal covalent bond (e.g., metal carboxylates) are termed ''metalorganic'' compounds.While carbon is understood to strongly prefer formation of four covalent bonds, other exotic bonding schemes are also known.", "Carboranes are highly stable dodecahedral derivatives of the B12H122- unit, with one BH replaced with a CH+.", "Thus, the carbon is bonded to five boron atoms and one hydrogen atom.", "The cation (PhPAu)C contains an octahedral carbon bound to six phosphine-gold fragments.", "This phenomenon has been attributed to the aurophilicity of the gold ligands, which provide additional stabilization of an otherwise labile species.", "In nature, the iron-molybdenum cofactor (FeMoco) responsible for microbial nitrogen fixation likewise has an octahedral carbon center (formally a carbide, C(-IV)) bonded to six iron atoms.", "In 2016, it was confirmed that, in line with earlier theoretical predictions, the hexamethylbenzene dication contains a carbon atom with six bonds.", "More specifically, the dication could be described structurally by the formulation MeC(η5-C5Me5)2+, making it an \"organic metallocene\" in which a MeC3+ fragment is bonded to a η5-C5Me5− fragment through all five of the carbons of the ring.This anthracene derivative contains a carbon atom with 5 formal electron pairs around it.It is important to note that in the cases above, each of the bonds to carbon contain less than two formal electron pairs.", "Thus, the formal electron count of these species does not exceed an octet.", "This makes them hypercoordinate but not hypervalent.", "Even in cases of alleged 10-C-5 species (that is, a carbon with five ligands and a formal electron count of ten), as reported by Akiba and co-workers, electronic structure calculations conclude that the electron population around carbon is still less than eight, as is true for other compounds featuring four-electron three-center bonding." ], [ "History and etymology", "Antoine Lavoisier in his youthThe English name ''carbon'' comes from the Latin ''carbo'' for coal and charcoal, whence also comes the French ''charbon'', meaning charcoal.", "In German, Dutch and Danish, the names for carbon are ''Kohlenstoff'', ''koolstof'', and ''kulstof'' respectively, all literally meaning coal-substance.Carbon was discovered in prehistory and was known in the forms of soot and charcoal to the earliest human civilizations.", "Diamonds were known probably as early as 2500 BCE in China, while carbon in the form of charcoal was made around Roman times by the same chemistry as it is today, by heating wood in a pyramid covered with clay to exclude air.Carl Wilhelm Scheele In 1722, René Antoine Ferchault de Réaumur demonstrated that iron was transformed into steel through the absorption of some substance, now known to be carbon.", "In 1772, Antoine Lavoisier showed that diamonds are a form of carbon; when he burned samples of charcoal and diamond and found that neither produced any water and that both released the same amount of carbon dioxide per gram.", "In 1779, Carl Wilhelm Scheele showed that graphite, which had been thought of as a form of lead, was instead identical with charcoal but with a small admixture of iron, and that it gave \"aerial acid\" (his name for carbon dioxide) when oxidized with nitric acid.", "In 1786, the French scientists Claude Louis Berthollet, Gaspard Monge and C. A. Vandermonde confirmed that graphite was mostly carbon by oxidizing it in oxygen in much the same way Lavoisier had done with diamond.", "Some iron again was left, which the French scientists thought was necessary to the graphite structure.", "In their publication they proposed the name ''carbone'' (Latin ''carbonum'') for the element in graphite which was given off as a gas upon burning graphite.", "Antoine Lavoisier then listed carbon as an element in his 1789 textbook.A new allotrope of carbon, fullerene, that was discovered in 1985 includes nanostructured forms such as buckyballs and nanotubes.", "Their discoverers – Robert Curl, Harold Kroto, and Richard Smalley – received the Nobel Prize in Chemistry in 1996.The resulting renewed interest in new forms led to the discovery of further exotic allotropes, including glassy carbon, and the realization that \"amorphous carbon\" is not strictly amorphous." ], [ "Production", "===Graphite===Commercially viable natural deposits of graphite occur in many parts of the world, but the most important sources economically are in China, India, Brazil, and North Korea.", "Graphite deposits are of metamorphic origin, found in association with quartz, mica, and feldspars in schists, gneisses, and metamorphosed sandstones and limestone as lenses or veins, sometimes of a metre or more in thickness.", "Deposits of graphite in Borrowdale, Cumberland, England were at first of sufficient size and purity that, until the 19th century, pencils were made by sawing blocks of natural graphite into strips before encasing the strips in wood.", "Today, smaller deposits of graphite are obtained by crushing the parent rock and floating the lighter graphite out on water.There are three types of natural graphite—amorphous, flake or crystalline flake, and vein or lump.", "Amorphous graphite is the lowest quality and most abundant.", "Contrary to science, in industry \"amorphous\" refers to very small crystal size rather than complete lack of crystal structure.", "Amorphous is used for lower value graphite products and is the lowest priced graphite.", "Large amorphous graphite deposits are found in China, Europe, Mexico and the United States.", "Flake graphite is less common and of higher quality than amorphous; it occurs as separate plates that crystallized in metamorphic rock.", "Flake graphite can be four times the price of amorphous.", "Good quality flakes can be processed into expandable graphite for many uses, such as flame retardants.", "The foremost deposits are found in Austria, Brazil, Canada, China, Germany and Madagascar.", "Vein or lump graphite is the rarest, most valuable, and highest quality type of natural graphite.", "It occurs in veins along intrusive contacts in solid lumps, and it is only commercially mined in Sri Lanka.According to the USGS, world production of natural graphite was 1.1 million tonnes in 2010, to which China contributed 800,000 t, India 130,000 t, Brazil 76,000 t, North Korea 30,000 t and Canada 25,000 t. No natural graphite was reported mined in the United States, but 118,000 t of synthetic graphite with an estimated value of $998 million was produced in 2009.===Diamond===Diamond output in 2005The diamond supply chain is controlled by a limited number of powerful businesses, and is also highly concentrated in a small number of locations around the world (see figure).Only a very small fraction of the diamond ore consists of actual diamonds.", "The ore is crushed, during which care has to be taken in order to prevent larger diamonds from being destroyed in this process and subsequently the particles are sorted by density.", "Today, diamonds are located in the diamond-rich density fraction with the help of X-ray fluorescence, after which the final sorting steps are done by hand.", "Before the use of X-rays became commonplace, the separation was done with grease belts; diamonds have a stronger tendency to stick to grease than the other minerals in the ore.Historically diamonds were known to be found only in alluvial deposits in southern India.", "India led the world in diamond production from the time of their discovery in approximately the 9th century BC to the mid-18th century AD, but the commercial potential of these sources had been exhausted by the late 18th century and at that time India was eclipsed by Brazil where the first non-Indian diamonds were found in 1725.Diamond production of primary deposits (kimberlites and lamproites) only started in the 1870s after the discovery of the diamond fields in South Africa.", "Production has increased over time and an accumulated total of over 4.5 billion carats have been mined since that date.", "Most commercially viable diamond deposits were in Russia, Botswana, Australia and the Democratic Republic of Congo.", "By 2005, Russia produced almost one-fifth of the global diamond output (mostly in Yakutia territory; for example, Mir pipe and Udachnaya pipe) but the Argyle mine in Australia became the single largest source, producing 14 million carats in 2018.New finds, the Canadian mines at Diavik and Ekati, are expected to become even more valuable owing to their production of gem quality stones.In the United States, diamonds have been found in Arkansas, Colorado, and Montana.", "In 2004, a startling discovery of a microscopic diamond in the United States led to the January 2008 bulk-sampling of kimberlite pipes in a remote part of Montana." ], [ "Applications", "Pencil leads for mechanical pencils are made of graphite (often mixed with a clay or synthetic binder).Sticks of vine and compressed charcoalA cloth of woven carbon fibresSilicon carbide single crystalThe ''C'' fullerene in crystalline formTungsten carbide endmillsCarbon is essential to all known living systems, and without it life as we know it could not exist (see alternative biochemistry).", "The major economic use of carbon other than food and wood is in the form of hydrocarbons, most notably the fossil fuel methane gas and crude oil (petroleum).", "Crude oil is distilled in refineries by the petrochemical industry to produce gasoline, kerosene, and other products.", "Cellulose is a natural, carbon-containing polymer produced by plants in the form of wood, cotton, linen, and hemp.", "Cellulose is used primarily for maintaining structure in plants.", "Commercially valuable carbon polymers of animal origin include wool, cashmere, and silk.", "Plastics are made from synthetic carbon polymers, often with oxygen and nitrogen atoms included at regular intervals in the main polymer chain.", "The raw materials for many of these synthetic substances come from crude oil.The uses of carbon and its compounds are extremely varied.", "It can form alloys with iron, of which the most common is carbon steel.", "Graphite is combined with clays to form the 'lead' used in pencils used for writing and drawing.", "It is also used as a lubricant and a pigment, as a moulding material in glass manufacture, in electrodes for dry batteries and in electroplating and electroforming, in brushes for electric motors, and as a neutron moderator in nuclear reactors.Charcoal is used as a drawing material in artwork, barbecue grilling, iron smelting, and in many other applications.", "Wood, coal and oil are used as fuel for production of energy and heating.", "Gem quality diamond is used in jewelry, and industrial diamonds are used in drilling, cutting and polishing tools for machining metals and stone.", "Plastics are made from fossil hydrocarbons, and carbon fiber, made by pyrolysis of synthetic polyester fibers is used to reinforce plastics to form advanced, lightweight composite materials.Carbon fiber is made by pyrolysis of extruded and stretched filaments of polyacrylonitrile (PAN) and other organic substances.", "The crystallographic structure and mechanical properties of the fiber depend on the type of starting material, and on the subsequent processing.", "Carbon fibers made from PAN have structure resembling narrow filaments of graphite, but thermal processing may re-order the structure into a continuous rolled sheet.", "The result is fibers with higher specific tensile strength than steel.Carbon black is used as the black pigment in printing ink, artist's oil paint, and water colours, carbon paper, automotive finishes, India ink and laser printer toner.", "Carbon black is also used as a filler in rubber products such as tyres and in plastic compounds.", "Activated charcoal is used as an absorbent and adsorbent in filter material in applications as diverse as gas masks, water purification, and kitchen extractor hoods, and in medicine to absorb toxins, poisons, or gases from the digestive system.", "Carbon is used in chemical reduction at high temperatures.", "Coke is used to reduce iron ore into iron (smelting).", "Case hardening of steel is achieved by heating finished steel components in carbon powder.", "Carbides of silicon, tungsten, boron, and titanium are among the hardest known materials, and are used as abrasives in cutting and grinding tools.", "Carbon compounds make up most of the materials used in clothing, such as natural and synthetic textiles and leather, and almost all of the interior surfaces in the built environment other than glass, stone, drywall and metal.===Diamonds===The diamond industry falls into two categories: one dealing with gem-grade diamonds and the other, with industrial-grade diamonds.", "While a large trade in both types of diamonds exists, the two markets function dramatically differently.Unlike precious metals such as gold or platinum, gem diamonds do not trade as a commodity: there is a substantial mark-up in the sale of diamonds, and there is not a very active market for resale of diamonds.Industrial diamonds are valued mostly for their hardness and heat conductivity, with the gemological qualities of clarity and color being mostly irrelevant.", "About 80% of mined diamonds (equal to about 100 million carats or 20 tonnes annually) are unsuitable for use as gemstones and relegated for industrial use (known as ''bort)''.", "Synthetic diamonds, invented in the 1950s, found almost immediate industrial applications; 3 billion carats (600 tonnes) of synthetic diamond is produced annually.The dominant industrial use of diamond is in cutting, drilling, grinding, and polishing.", "Most of these applications do not require large diamonds; in fact, most diamonds of gem-quality except for their small size can be used industrially.", "Diamonds are embedded in drill tips or saw blades, or ground into a powder for use in grinding and polishing applications.", "Specialized applications include use in laboratories as containment for high-pressure experiments (see diamond anvil cell), high-performance bearings, and limited use in specialized windows.", "With the continuing advances in the production of synthetic diamonds, new applications are becoming feasible.", "Garnering much excitement is the possible use of diamond as a semiconductor suitable for microchips, and because of its exceptional heat conductance property, as a heat sink in electronics." ], [ "Precautions", "Worker at carbon black plant in Sunray, Texas (photo by John Vachon, 1942)Gross pathology of lung showing centrilobular emphysema characteristic of smoking.", "Closeup of fixed, cut surface shows multiple cavities lined by heavy black carbon deposits.Pure carbon has extremely low toxicity to humans and can be handled safely in the form of graphite or charcoal.", "It is resistant to dissolution or chemical attack, even in the acidic contents of the digestive tract.", "Consequently, once it enters into the body's tissues it is likely to remain there indefinitely.", "Carbon black was probably one of the first pigments to be used for tattooing, and Ötzi the Iceman was found to have carbon tattoos that survived during his life and for 5200 years after his death.", "Inhalation of coal dust or soot (carbon black) in large quantities can be dangerous, irritating lung tissues and causing the congestive lung disease, coalworker's pneumoconiosis.", "Diamond dust used as an abrasive can be harmful if ingested or inhaled.", "Microparticles of carbon are produced in diesel engine exhaust fumes, and may accumulate in the lungs.", "In these examples, the harm may result from contaminants (e.g., organic chemicals, heavy metals) rather than from the carbon itself.Carbon generally has low toxicity to life on Earth; but carbon nanoparticles are deadly to ''Drosophila''.Carbon may burn vigorously and brightly in the presence of air at high temperatures.", "Large accumulations of coal, which have remained inert for hundreds of millions of years in the absence of oxygen, may spontaneously combust when exposed to air in coal mine waste tips, ship cargo holds and coal bunkers, and storage dumps.In nuclear applications where graphite is used as a neutron moderator, accumulation of Wigner energy followed by a sudden, spontaneous release may occur.", "Annealing to at least 250 °C can release the energy safely, although in the Windscale fire the procedure went wrong, causing other reactor materials to combust.The great variety of carbon compounds include such lethal poisons as tetrodotoxin, the lectin ricin from seeds of the castor oil plant ''Ricinus communis'', cyanide (CN), and carbon monoxide; and such essentials to life as glucose and protein." ], [ "See also", "* Carbon chauvinism* Carbon detonation* Carbon footprint* Carbon star* Carbon planet* Gas carbon* Low-carbon economy* Timeline of carbon nanotubes" ], [ "References" ], [ "Bibliography", "* *" ], [ "External links", "* * Carbon at ''The Periodic Table of Videos'' (University of Nottingham)* Carbon on Britannica* Extensive Carbon page at asu.edu (archived 18 June 2010)* Electrochemical uses of carbon (archived 9 November 2001)* Carbon—Super Stuff.", "Animation with sound and interactive 3D-models.", "(archived 9 November 2012)" ] ]

[ [ "Computer data storage" ], [ "Introduction", "GiB of SDRAM mounted in a computer.", "An example of ''primary storage''.GB PATA hard disk drive (HDD) from 1999.When connected to a computer it serves as ''secondary'' storage.GB SDLT tape cartridge, an example of ''off-line'' storage.", "When used within a robotic tape library, it is classified as ''tertiary'' storage instead.Read/Write DVD drive with cradle for media extended'''Computer data storage''' is a technology consisting of computer components and recording media that are used to retain digital data.", "It is a core function and fundamental component of computers.The central processing unit (CPU) of a computer is what manipulates data by performing computations.", "In practice, almost all computers use a storage hierarchy, which puts fast but expensive and small storage options close to the CPU and slower but less expensive and larger options further away.", "Generally, the fast technologies are referred to as \"memory\", while slower persistent technologies are referred to as \"storage\".Even the first computer designs, Charles Babbage's Analytical Engine and Percy Ludgate's Analytical Machine, clearly distinguished between processing and memory (Babbage stored numbers as rotations of gears, while Ludgate stored numbers as displacements of rods in shuttles).", "This distinction was extended in the Von Neumann architecture, where the CPU consists of two main parts: The control unit and the arithmetic logic unit (ALU).", "The former controls the flow of data between the CPU and memory, while the latter performs arithmetic and logical operations on data." ], [ "Functionality", "Without a significant amount of memory, a computer would merely be able to perform fixed operations and immediately output the result.", "It would have to be reconfigured to change its behavior.", "This is acceptable for devices such as desk calculators, digital signal processors, and other specialized devices.", "Von Neumann machines differ in having a memory in which they store their operating instructions and data.", "Such computers are more versatile in that they do not need to have their hardware reconfigured for each new program, but can simply be reprogrammed with new in-memory instructions; they also tend to be simpler to design, in that a relatively simple processor may keep state between successive computations to build up complex procedural results.", "Most modern computers are von Neumann machines." ], [ "Data organization and representation", "A modern digital computer represents data using the binary numeral system.", "Text, numbers, pictures, audio, and nearly any other form of information can be converted into a string of bits, or binary digits, each of which has a value of 0 or 1.The most common unit of storage is the byte, equal to 8 bits.", "A piece of information can be handled by any computer or device whose storage space is large enough to accommodate ''the binary representation of the piece of information'', or simply data.", "For example, the complete works of Shakespeare, about 1250 pages in print, can be stored in about five megabytes (40 million bits) with one byte per character.Data are encoded by assigning a bit pattern to each character, digit, or multimedia object.", "Many standards exist for encoding (e.g.", "character encodings like ASCII, image encodings like JPEG, and video encodings like MPEG-4).By adding bits to each encoded unit, redundancy allows the computer to detect errors in coded data and correct them based on mathematical algorithms.", "Errors generally occur in low probabilities due to random bit value flipping, or \"physical bit fatigue\", loss of the physical bit in the storage of its ability to maintain a distinguishable value (0 or 1), or due to errors in inter or intra-computer communication.", "A random bit flip (e.g.", "due to random radiation) is typically corrected upon detection.", "A bit or a group of malfunctioning physical bits (the specific defective bit is not always known; group definition depends on the specific storage device) is typically automatically fenced out, taken out of use by the device, and replaced with another functioning equivalent group in the device, where the corrected bit values are restored (if possible).", "The cyclic redundancy check (CRC) method is typically used in communications and storage for error detection.", "A detected error is then retried.Data compression methods allow in many cases (such as a database) to represent a string of bits by a shorter bit string (\"compress\") and reconstruct the original string (\"decompress\") when needed.", "This utilizes substantially less storage (tens of percent) for many types of data at the cost of more computation (compress and decompress when needed).", "Analysis of the trade-off between storage cost saving and costs of related computations and possible delays in data availability is done before deciding whether to keep certain data compressed or not.For security reasons, certain types of data (e.g.", "credit card information) may be kept encrypted in storage to prevent the possibility of unauthorized information reconstruction from chunks of storage snapshots." ], [ "Hierarchy of storage", "Various forms of storage, divided according to their distance from the central processing unit.", "The fundamental components of a general-purpose computer are arithmetic and logic unit, control circuitry, storage space, and input/output devices.", "Technology and capacity as in common home computers around 2005.Generally, the lower a storage is in the hierarchy, the lesser its bandwidth and the greater its access latency is from the CPU.", "This traditional division of storage to primary, secondary, tertiary, and off-line storage is also guided by cost per bit.In contemporary usage, ''memory'' is usually fast but temporary semiconductor read-write memory, typically DRAM (dynamic RAM) or other such devices.", "''Storage'' consists of storage devices and their media not directly accessible by the CPU (secondary or tertiary storage), typically hard disk drives, optical disc drives, and other devices slower than RAM but non-volatile (retaining contents when powered down).Historically, ''memory'' has, depending on technology, been called ''central memory'', ''core memory'', ''core storage'', ''drum'', ''main memory'', ''real storage'', or ''internal memory''.", "Meanwhile, slower persistent storage devices have been referred to as ''secondary storage'', ''external memory'', or ''auxiliary/peripheral storage''.=== Primary storage ===''Primary storage'' (also known as ''main memory'', ''internal memory'', or ''prime memory''), often referred to simply as ''memory'', is the only one directly accessible to the CPU.", "The CPU continuously reads instructions stored there and executes them as required.", "Any data actively operated on is also stored there in a uniform manner.Historically, early computers used delay lines, Williams tubes, or rotating magnetic drums as primary storage.", "By 1954, those unreliable methods were mostly replaced by magnetic-core memory.", "Core memory remained dominant until the 1970s, when advances in integrated circuit technology allowed semiconductor memory to become economically competitive.This led to modern random-access memory (RAM).", "It is small-sized, light, but quite expensive at the same time.", "The particular types of RAM used for primary storage are volatile, meaning that they lose the information when not powered.", "Besides storing opened programs, it serves as disk cache and write buffer to improve both reading and writing performance.", "Operating systems borrow RAM capacity for caching so long as it's not needed by running software.", "Spare memory can be utilized as RAM drive for temporary high-speed data storage.As shown in the diagram, traditionally there are two more sub-layers of the primary storage, besides main large-capacity RAM:* Processor registers are located inside the processor.", "Each register typically holds a word of data (often 32 or 64 bits).", "CPU instructions instruct the arithmetic logic unit to perform various calculations or other operations on this data (or with the help of it).", "Registers are the fastest of all forms of computer data storage.", "* Processor cache is an intermediate stage between ultra-fast registers and much slower main memory.", "It was introduced solely to improve the performance of computers.", "Most actively used information in the main memory is just duplicated in the cache memory, which is faster, but of much lesser capacity.", "On the other hand, main memory is much slower, but has a much greater storage capacity than processor registers.", "Multi-level hierarchical cache setup is also commonly used—''primary cache'' being smallest, fastest and located inside the processor; ''secondary cache'' being somewhat larger and slower.", "Main memory is directly or indirectly connected to the central processing unit via a ''memory bus''.", "It is actually two buses (not on the diagram): an address bus and a data bus.", "The CPU firstly sends a number through an address bus, a number called memory address, that indicates the desired location of data.", "Then it reads or writes the data in the memory cells using the data bus.", "Additionally, a memory management unit (MMU) is a small device between CPU and RAM recalculating the actual memory address, for example to provide an abstraction of virtual memory or other tasks.As the RAM types used for primary storage are volatile (uninitialized at start up), a computer containing only such storage would not have a source to read instructions from, in order to start the computer.", "Hence, non-volatile primary storage containing a small startup program (BIOS) is used to bootstrap the computer, that is, to read a larger program from non-volatile ''secondary'' storage to RAM and start to execute it.", "A non-volatile technology used for this purpose is called ROM, for read-only memory (the terminology may be somewhat confusing as most ROM types are also capable of ''random access'').Many types of \"ROM\" are not literally ''read only'', as updates to them are possible; however it is slow and memory must be erased in large portions before it can be re-written.", "Some embedded systems run programs directly from ROM (or similar), because such programs are rarely changed.", "Standard computers do not store non-rudimentary programs in ROM, and rather, use large capacities of secondary storage, which is non-volatile as well, and not as costly.Recently, ''primary storage'' and ''secondary storage'' in some uses refer to what was historically called, respectively, ''secondary storage'' and ''tertiary storage''.=== Secondary storage ===''Secondary storage'' (also known as ''external memory'' or ''auxiliary storage'') differs from primary storage in that it is not directly accessible by the CPU.", "The computer usually uses its input/output channels to access secondary storage and transfer the desired data to primary storage.", "Secondary storage is non-volatile (retaining data when its power is shut off).", "Modern computer systems typically have two orders of magnitude more secondary storage than primary storage because secondary storage is less expensive.In modern computers, hard disk drives (HDDs) or solid-state drives (SSDs) are usually used as secondary storage.", "The access time per byte for HDDs or SSDs is typically measured in milliseconds (thousandths of a second), while the access time per byte for primary storage is measured in nanoseconds (billionths of a second).", "Thus, secondary storage is significantly slower than primary storage.", "Rotating optical storage devices, such as CD and DVD drives, have even longer access times.", "Other examples of secondary storage technologies include USB flash drives, floppy disks, magnetic tape, paper tape, punched cards, and RAM disks.Once the disk read/write head on HDDs reaches the proper placement and the data, subsequent data on the track are very fast to access.", "To reduce the seek time and rotational latency, data are transferred to and from disks in large contiguous blocks.", "Sequential or block access on disks is orders of magnitude faster than random access, and many sophisticated paradigms have been developed to design efficient algorithms based on sequential and block access.", "Another way to reduce the I/O bottleneck is to use multiple disks in parallel to increase the bandwidth between primary and secondary memory.Secondary storage is often formatted according to a file system format, which provides the abstraction necessary to organize data into files and directories, while also providing metadata describing the owner of a certain file, the access time, the access permissions, and other information.Most computer operating systems use the concept of virtual memory, allowing the utilization of more primary storage capacity than is physically available in the system.", "As the primary memory fills up, the system moves the least-used chunks (pages) to a swap file or page file on secondary storage, retrieving them later when needed.", "If a lot of pages are moved to slower secondary storage, the system performance is degraded.=== Tertiary storage ===A large tape library, with tape cartridges placed on shelves in the front, and a robotic arm moving in the back.", "The visible height of the library is about 180 cm.", "''Tertiary storage'' or ''tertiary memory'' is a level below secondary storage.", "Typically, it involves a robotic mechanism which will ''mount'' (insert) and ''dismount'' removable mass storage media into a storage device according to the system's demands; such data are often copied to secondary storage before use.", "It is primarily used for archiving rarely accessed information since it is much slower than secondary storage (e.g.", "5–60 seconds vs. 1–10 milliseconds).", "This is primarily useful for extraordinarily large data stores, accessed without human operators.", "Typical examples include tape libraries and optical jukeboxes.When a computer needs to read information from the tertiary storage, it will first consult a catalog database to determine which tape or disc contains the information.", "Next, the computer will instruct a robotic arm to fetch the medium and place it in a drive.", "When the computer has finished reading the information, the robotic arm will return the medium to its place in the library.Tertiary storage is also known as ''nearline storage'' because it is \"near to online\".", "The formal distinction between online, nearline, and offline storage is:* Online storage is immediately available for I/O.", "* Nearline storage is not immediately available, but can be made online quickly without human intervention.", "* Offline storage is not immediately available, and requires some human intervention to become online.For example, always-on spinning hard disk drives are online storage, while spinning drives that spin down automatically, such as in massive arrays of idle disks (MAID), are nearline storage.", "Removable media such as tape cartridges that can be automatically loaded, as in tape libraries, are nearline storage, while tape cartridges that must be manually loaded are offline storage.=== Off-line storage ===''Off-line storage'' is computer data storage on a medium or a device that is not under the control of a processing unit.", "The medium is recorded, usually in a secondary or tertiary storage device, and then physically removed or disconnected.", "It must be inserted or connected by a human operator before a computer can access it again.", "Unlike tertiary storage, it cannot be accessed without human interaction.Off-line storage is used to transfer information since the detached medium can easily be physically transported.", "Additionally, it is useful for cases of disaster, where, for example, a fire destroys the original data, a medium in a remote location will be unaffected, enabling disaster recovery.", "Off-line storage increases general information security since it is physically inaccessible from a computer, and data confidentiality or integrity cannot be affected by computer-based attack techniques.", "Also, if the information stored for archival purposes is rarely accessed, off-line storage is less expensive than tertiary storage.In modern personal computers, most secondary and tertiary storage media are also used for off-line storage.", "Optical discs and flash memory devices are the most popular, and to a much lesser extent removable hard disk drives; older examples include floppy disks and Zip disks.", "In enterprise uses, magnetic tape cartridges are predominant; older examples include open-reel magnetic tape and punched cards." ], [ "Characteristics of storage", "laptop DDR2 RAMStorage technologies at all levels of the storage hierarchy can be differentiated by evaluating certain core characteristics as well as measuring characteristics specific to a particular implementation.", "These core characteristics are volatility, mutability, accessibility, and addressability.", "For any particular implementation of any storage technology, the characteristics worth measuring are capacity and performance.+ Overview Characteristic Hard disk drive Optical disc Flash memory Random-access memory Linear tape-open Technology Magnetic disk Laser beam Semiconductor Magnetic tape Volatility No No No Volatile No Random access Yes Yes Yes Yes No Latency (access time) ~15 ms (swift) ~150 ms (moderate) None (instant) None (instant) Lack of random access (very slow) Controller Internal External Internal Internal External Failure with imminent data loss Head crash — Circuitry — Error detection Diagnostic (S.M.A.R.T.)", "Error rate measurement Indicated by downward spikes in transfer rates (Short-term storage) Unknown Price per space Low Low High Very high Very low (but expensive drives) Price per unit Moderate Low Moderate High Moderate (but expensive drives) Main application Mid-term archival, routine backups, server, workstation storage expansion Long-term archival, hard copy distribution Portable electronics; operating system Real-time Long-term archival=== Volatility ===Non-volatile memory retains the stored information even if not constantly supplied with electric power.", "It is suitable for long-term storage of information.", "Volatile memory requires constant power to maintain the stored information.", "The fastest memory technologies are volatile ones, although that is not a universal rule.", "Since the primary storage is required to be very fast, it predominantly uses volatile memory.Dynamic random-access memory is a form of volatile memory that also requires the stored information to be periodically reread and rewritten, or refreshed, otherwise it would vanish.", "Static random-access memory is a form of volatile memory similar to DRAM with the exception that it never needs to be refreshed as long as power is applied; it loses its content when the power supply is lost.An uninterruptible power supply (UPS) can be used to give a computer a brief window of time to move information from primary volatile storage into non-volatile storage before the batteries are exhausted.", "Some systems, for example EMC Symmetrix, have integrated batteries that maintain volatile storage for several minutes.=== Mutability ===; Read/write storage or mutable storage : Allows information to be overwritten at any time.", "A computer without some amount of read/write storage for primary storage purposes would be useless for many tasks.", "Modern computers typically use read/write storage also for secondary storage.", "; Slow write, fast read storage : Read/write storage which allows information to be overwritten multiple times, but with the write operation being much slower than the read operation.", "Examples include CD-RW and SSD.", "; Write once storage : Write once read many (WORM) allows the information to be written only once at some point after manufacture.", "Examples include semiconductor programmable read-only memory and CD-R.; Read only storage : Retains the information stored at the time of manufacture.", "Examples include mask ROM ICs and CD-ROM.=== Accessibility ===; Random access: Any location in storage can be accessed at any moment in approximately the same amount of time.", "Such characteristic is well suited for primary and secondary storage.", "Most semiconductor memories, flash memories and hard disk drives provide random access, though both semiconductor and flash memories have minimal latency when compared to hard disk drives, as no mechanical parts need to be moved.", "; Sequential access: The accessing of pieces of information will be in a serial order, one after the other; therefore the time to access a particular piece of information depends upon which piece of information was last accessed.", "Such characteristic is typical of off-line storage.=== Addressability ===; Location-addressable : Each individually accessible unit of information in storage is selected with its numerical memory address.", "In modern computers, location-addressable storage usually limits to primary storage, accessed internally by computer programs, since location-addressability is very efficient, but burdensome for humans.", "; File addressable: Information is divided into ''files'' of variable length, and a particular file is selected with human-readable directory and file names.", "The underlying device is still location-addressable, but the operating system of a computer provides the file system abstraction to make the operation more understandable.", "In modern computers, secondary, tertiary and off-line storage use file systems.", "; Content-addressable: Each individually accessible unit of information is selected based on the basis of (part of) the contents stored there.", "Content-addressable storage can be implemented using software (computer program) or hardware (computer device), with hardware being faster but more expensive option.", "Hardware content addressable memory is often used in a computer's CPU cache.=== Capacity ===; Raw capacity: The total amount of stored information that a storage device or medium can hold.", "It is expressed as a quantity of bits or bytes (e.g.", "10.4 megabytes).", "; Memory storage density: The compactness of stored information.", "It is the storage capacity of a medium divided with a unit of length, area or volume (e.g.", "1.2 megabytes per square inch).=== Performance ===; Latency: The time it takes to access a particular location in storage.", "The relevant unit of measurement is typically nanosecond for primary storage, millisecond for secondary storage, and second for tertiary storage.", "It may make sense to separate read latency and write latency (especially for non-volatile memory) and in case of sequential access storage, minimum, maximum and average latency.", "; Throughput: The rate at which information can be read from or written to the storage.", "In computer data storage, throughput is usually expressed in terms of megabytes per second (MB/s), though bit rate may also be used.", "As with latency, read rate and write rate may need to be differentiated.", "Also accessing media sequentially, as opposed to randomly, typically yields maximum throughput.", "; Granularity: The size of the largest \"chunk\" of data that can be efficiently accessed as a single unit, e.g.", "without introducing additional latency.", ";Reliability: The probability of spontaneous bit value change under various conditions, or overall failure rate.Utilities such as hdparm and sar can be used to measure IO performance in Linux.=== Energy use ===* Storage devices that reduce fan usage automatically shut-down during inactivity, and low power hard drives can reduce energy consumption by 90 percent.", "* 2.5-inch hard disk drives often consume less power than larger ones.", "Low capacity solid-state drives have no moving parts and consume less power than hard disks.", "Also, memory may use more power than hard disks.", "Large caches, which are used to avoid hitting the memory wall, may also consume a large amount of power.=== Security ===Full disk encryption, volume and virtual disk encryption, andor file/folder encryption is readily available for most storage devices.Hardware memory encryption is available in Intel Architecture, supporting Total Memory Encryption (TME) and page granular memory encryption with multiple keys (MKTME).", "and in SPARC M7 generation since October 2015.=== Vulnerability and reliability ===S.M.A.R.T.", "software warning suggests impending hard drive failure.Distinct types of data storage have different points of failure and various methods of predictive failure analysis.Vulnerabilities that can instantly lead to total loss are head crashing on mechanical hard drives and failure of electronic components on flash storage.==== Error detection ====Error rate measurement on a DVD+R.", "The minor errors are correctable and within a healthy range.Impending failure on hard disk drives is estimable using S.M.A.R.T.", "diagnostic data that includes the hours of operation and the count of spin-ups, though its reliability is disputed.Flash storage may experience downspiking transfer rates as a result of accumulating errors, which the flash memory controller attempts to correct.The health of optical media can be determined by measuring correctable minor errors, of which high counts signify deteriorating and/or low-quality media.", "Too many consecutive minor errors can lead to data corruption.", "Not all vendors and models of optical drives support error scanning." ], [ "{{anchor|media}}Storage media", ", the most commonly used data storage media are semiconductor, magnetic, and optical, while paper still sees some limited usage.", "Some other fundamental storage technologies, such as all-flash arrays (AFAs) are proposed for development.=== Semiconductor ===Semiconductor memory uses semiconductor-based integrated circuit (IC) chips to store information.", "Data are typically stored in metal–oxide–semiconductor (MOS) memory cells.", "A semiconductor memory chip may contain millions of memory cells, consisting of tiny MOS field-effect transistors (MOSFETs) and/or MOS capacitors.", "Both ''volatile'' and ''non-volatile'' forms of semiconductor memory exist, the former using standard MOSFETs and the latter using floating-gate MOSFETs.In modern computers, primary storage almost exclusively consists of dynamic volatile semiconductor random-access memory (RAM), particularly dynamic random-access memory (DRAM).", "Since the turn of the century, a type of non-volatile floating-gate semiconductor memory known as flash memory has steadily gained share as off-line storage for home computers.", "Non-volatile semiconductor memory is also used for secondary storage in various advanced electronic devices and specialized computers that are designed for them.As early as 2006, notebook and desktop computer manufacturers started using flash-based solid-state drives (SSDs) as default configuration options for the secondary storage either in addition to or instead of the more traditional HDD.=== Magnetic ===Magnetic storage uses different patterns of magnetization on a magnetically coated surface to store information.", "Magnetic storage is ''non-volatile''.", "The information is accessed using one or more read/write heads which may contain one or more recording transducers.", "A read/write head only covers a part of the surface so that the head or medium or both must be moved relative to another in order to access data.", "In modern computers, magnetic storage will take these forms:* Magnetic disk;** Floppy disk, used for off-line storage;** Hard disk drive, used for secondary storage.", "* Magnetic tape, used for tertiary and off-line storage;* Carousel memory (magnetic rolls).In early computers, magnetic storage was also used as:* Primary storage in a form of magnetic memory, or core memory, core rope memory, thin-film memory and/or twistor memory;* Tertiary (e.g.", "NCR CRAM) or off line storage in the form of magnetic cards;* Magnetic tape was then often used for secondary storage.Magnetic storage does not have a definite limit of rewriting cycles like flash storage and re-writeable optical media, as altering magnetic fields causes no physical wear.", "Rather, their life span is limited by mechanical parts.=== Optical ===Optical storage, the typical optical disc, stores information in deformities on the surface of a circular disc and reads this information by illuminating the surface with a laser diode and observing the reflection.", "Optical disc storage is ''non-volatile''.", "The deformities may be permanent (read only media), formed once (write once media) or reversible (recordable or read/write media).", "The following forms are in common use :* CD, CD-ROM, DVD, BD-ROM: Read only storage, used for mass distribution of digital information (music, video, computer programs);* CD-R, DVD-R, DVD+R, BD-R: Write once storage, used for tertiary and off-line storage;* CD-RW, DVD-RW, DVD+RW, DVD-RAM, BD-RE: Slow write, fast read storage, used for tertiary and off-line storage;* Ultra Density Optical or UDO is similar in capacity to BD-R or BD-RE and is slow write, fast read storage used for tertiary and off-line storage.Magneto-optical disc storage is optical disc storage where the magnetic state on a ferromagnetic surface stores information.", "The information is read optically and written by combining magnetic and optical methods.", "Magneto-optical disc storage is ''non-volatile'', ''sequential access'', slow write, fast read storage used for tertiary and off-line storage.3D optical data storage has also been proposed.Light induced magnetization melting in magnetic photoconductors has also been proposed for high-speed low-energy consumption magneto-optical storage.=== Paper ===Paper data storage, typically in the form of paper tape or punched cards, has long been used to store information for automatic processing, particularly before general-purpose computers existed.", "Information was recorded by punching holes into the paper or cardboard medium and was read mechanically (or later optically) to determine whether a particular location on the medium was solid or contained a hole.", "Barcodes make it possible for objects that are sold or transported to have some computer-readable information securely attached.Relatively small amounts of digital data (compared to other digital data storage) may be backed up on paper as a matrix barcode for very long-term storage, as the longevity of paper typically exceeds even magnetic data storage.=== Other storage media or substrates ===; Vacuum-tube memory: A Williams tube used a cathode-ray tube, and a Selectron tube used a large vacuum tube to store information.", "These primary storage devices were short-lived in the market, since the Williams tube was unreliable, and the Selectron tube was expensive.", "; Electro-acoustic memory: Delay-line memory used sound waves in a substance such as mercury to store information.", "Delay-line memory was dynamic volatile, cycle sequential read/write storage, and was used for primary storage.", "; Optical tape: is a medium for optical storage, generally consisting of a long and narrow strip of plastic, onto which patterns can be written and from which the patterns can be read back.", "It shares some technologies with cinema film stock and optical discs, but is compatible with neither.", "The motivation behind developing this technology was the possibility of far greater storage capacities than either magnetic tape or optical discs.", "; Phase-change memory: uses different mechanical phases of phase-change material to store information in an X–Y addressable matrix and reads the information by observing the varying electrical resistance of the material.", "Phase-change memory would be non-volatile, random-access read/write storage, and might be used for primary, secondary and off-line storage.", "Most rewritable and many write-once optical disks already use phase-change material to store information.", "; Holographic data storage: stores information optically inside crystals or photopolymers.", "Holographic storage can utilize the whole volume of the storage medium, unlike optical disc storage, which is limited to a small number of surface layers.", "Holographic storage would be non-volatile, sequential-access, and either write-once or read/write storage.", "It might be used for secondary and off-line storage.", "See Holographic Versatile Disc (HVD).", "; Molecular memory: stores information in polymer that can store electric charge.", "Molecular memory might be especially suited for primary storage.", "The theoretical storage capacity of molecular memory is 10 terabits per square inch (16 Gbit/mm2).", "; Magnetic photoconductors: store magnetic information, which can be modified by low-light illumination.", "; DNA: stores information in DNA nucleotides.", "It was first done in 2012, when researchers achieved a ratio of 1.28 petabytes per gram of DNA.", "In March 2017 scientists reported that a new algorithm called a DNA fountain achieved 85% of the theoretical limit, at 215 petabytes per gram of DNA." ], [ "Related technologies", "=== Redundancy ===While a group of bits malfunction may be resolved by error detection and correction mechanisms (see above), storage device malfunction requires different solutions.", "The following solutions are commonly used and valid for most storage devices:* '''Device mirroring (replication)''' – A common solution to the problem is constantly maintaining an identical copy of device content on another device (typically of the same type).", "The downside is that this doubles the storage, and both devices (copies) need to be updated simultaneously with some overhead and possibly some delays.", "The upside is the possible concurrent reading of the same data group by two independent processes, which increases performance.", "When one of the replicated devices is detected to be defective, the other copy is still operational and is being utilized to generate a new copy on another device (usually available operational in a pool of stand-by devices for this purpose).", "* '''Redundant array of independent disks''' ('''RAID''') – This method generalizes the device mirroring above by allowing one device in a group of devices to fail and be replaced with the content restored (Device mirroring is RAID with ''n=2'').", "RAID groups of ''n=5'' or ''n=6'' are common.", "''n>2'' saves storage, when compared with ''n=2'', at the cost of more processing during both regular operation (with often reduced performance) and defective device replacement.Device mirroring and typical RAID are designed to handle a single device failure in the RAID group of devices.", "However, if a second failure occurs before the RAID group is completely repaired from the first failure, then data can be lost.", "The probability of a single failure is typically small.", "Thus the probability of two failures in the same RAID group in time proximity is much smaller (approximately the probability squared, i.e., multiplied by itself).", "If a database cannot tolerate even such a smaller probability of data loss, then the RAID group itself is replicated (mirrored).", "In many cases such mirroring is done geographically remotely, in a different storage array, to handle recovery from disasters (see disaster recovery above).=== Network connectivity ===A secondary or tertiary storage may connect to a computer utilizing computer networks.", "This concept does not pertain to the primary storage, which is shared between multiple processors to a lesser degree.", "* Direct-attached storage (DAS) is a traditional mass storage, that does not use any network.", "This is still a most popular approach.", "This retronym was coined recently, together with NAS and SAN.", "* Network-attached storage (NAS) is mass storage attached to a computer which another computer can access at file level over a local area network, a private wide area network, or in the case of online file storage, over the Internet.", "NAS is commonly associated with the NFS and CIFS/SMB protocols.", "* Storage area network (SAN) is a specialized network, that provides other computers with storage capacity.", "The crucial difference between NAS and SAN, is that NAS presents and manages file systems to client computers, while SAN provides access at block-addressing (raw) level, leaving it to attaching systems to manage data or file systems within the provided capacity.", "SAN is commonly associated with Fibre Channel networks.=== Robotic storage ===Large quantities of individual magnetic tapes, and optical or magneto-optical discs may be stored in robotic tertiary storage devices.", "In tape storage field they are known as tape libraries, and in optical storage field optical jukeboxes, or optical disk libraries per analogy.", "The smallest forms of either technology containing just one drive device are referred to as autoloaders or autochangers.Robotic-access storage devices may have a number of slots, each holding individual media, and usually one or more picking robots that traverse the slots and load media to built-in drives.", "The arrangement of the slots and picking devices affects performance.", "Important characteristics of such storage are possible expansion options: adding slots, modules, drives, robots.", "Tape libraries may have from 10 to more than 100,000 slots, and provide terabytes or petabytes of near-line information.", "Optical jukeboxes are somewhat smaller solutions, up to 1,000 slots.Robotic storage is used for backups, and for high-capacity archives in imaging, medical, and video industries.", "Hierarchical storage management is a most known archiving strategy of automatically ''migrating'' long-unused files from fast hard disk storage to libraries or jukeboxes.", "If the files are needed, they are ''retrieved'' back to disk." ], [ "See also", "=== Primary storage topics ===* Aperture (computer memory)* Dynamic random-access memory (DRAM)* Memory latency* Mass storage* Memory cell (disambiguation) * Memory management** Memory leak** Virtual memory* Memory protection* Page address register* Stable storage* Static random-access memory (SRAM)=== Secondary, tertiary and off-line storage topics ===* Cloud storage* Hybrid cloud storage* Data deduplication* Data proliferation* Data storage tag used for capturing research data* Disk utility* File system** List of file formats** Global filesystem* Flash memory* Geoplexing* Information repository* Noise-predictive maximum-likelihood detection* Object(-based) storage* Removable media* Solid-state drive* Spindle* Virtual tape library* Wait state* Write buffer* Write protection* Cold data=== Data storage conferences ===* Storage Networking World* Storage World Conference" ], [ "Notes" ], [ "References" ], [ "Further reading", "* * Memory & storage, Computer history museum" ] ]

[ [ "Conditional" ], [ "Introduction", "'''Conditional''' (if then) may refer to:*Causal conditional, if X then Y, where X is a cause of Y*Conditional probability, the probability of an event A given that another event B has occurred*Conditional proof, in logic: a proof that asserts a conditional, and proves that the antecedent leads to the consequent*Strict conditional, in philosophy, logic, and mathematics*Material conditional, in propositional calculus, or logical calculus in mathematics*Relevance conditional, in relevance logic*Conditional (computer programming), a statement or expression in computer programming languages*A conditional expression in computer programming languages such as ?", ":*Conditions in a contract" ], [ "Grammar and linguistics", "*Conditional mood (or conditional tense), a verb form in many languages*Conditional sentence, a sentence type used to refer to hypothetical situations and their consequences**Indicative conditional, a conditional sentence expressing \"if A then B\" in a natural language**Counterfactual conditional, a conditional sentence indicating what would be the case if its antecedent were true" ], [ "Other", "* \"Conditional\" (Laura Mvula song)* Conditional jockey, an apprentice jockey in British or Irish National Hunt racing* Conditional short-circuit current* Conditional Value-at-Risk" ], [ "See also", "*Condition (disambiguation)*Conditional statement (disambiguation)" ] ]

[ [ "Cone (disambiguation)" ], [ "Introduction", "A '''cone''' is a basic geometrical shape.", "'''Cone''' may also refer to:" ], [ "Mathematics", "*Cone (category theory)*Cone (formal languages)*Cone (graph theory), a graph in which one vertex is adjacent to all others*Cone (linear algebra), a subset of vector space*Mapping cone (homological algebra)*Cone (topology)*Conic bundle, a concept in algebraic geometry*Conical surface, generated by a moving line with one fixed point*Projective cone, the union of all lines that intersect a projective subspace and an arbitrary subset of some other disjoint subspace" ], [ "Computing", "*Cone tracing, a derivative of the ray-tracing algorithm that replaces rays, which have no thickness, with cones*Second-order cone programming, a library of routines that implements a predictor corrector variant of the semidefinite programming algorithm" ], [ "Astronomy", "*Cone Nebula (also known as NGC 2264), an H II region in the constellation of Monoceros*Ionization cone, cones of material extending out from spiral galaxies" ], [ "Engineering and physical science", "*Antenna blind cone, the volume of space that cannot be scanned by an antenna*Carbon nanocones, conical structures which are made predominantly from carbon and which have at least one dimension of the order one micrometer or smaller*Cone algorithm identifies surface particles quickly and accurately for three-dimensional clusters composed of discrete particles*Cone beam reconstruction, a method of X-ray scanning in microtomography*Cone calorimeter, a modern device used to study the fire behavior of small samples of various materials in condensed phase*Cone clutch serves the same purpose as a disk or plate clutch*Cone of depression occurs in an aquifer when groundwater is pumped from a well*Cone penetration test (CPT), an in situ testing method used to determine the geotechnical engineering properties of soils*Cone Penetrometer apparatus, an alternative method to the Casagrande Device in measuring the Liquid Limit of a soil sample*Conical intersection of two potential energy surfaces of the same spatial and spin symmetries*Conical measure, a type of graduated laboratory glassware with a conical cup and a notch on the top to facilitate pouring of liquids*Conical mill (or conical screen mill), a machine used to reduce the size of material in a uniform manner*Conical pendulum, a weight (or bob) fixed on the end of a string (or rod) suspended from a pivot*Conical scanning, a system used in early radar units to improve their accuracy*Helical cone beam computed tomography, a type of three-dimensional computed tomography*Hertzian cone, the cone of force that propagates through a brittle, amorphous or cryptocrystalline solid material from a point of impact*Nose cone, used to refer to the forwardmost section of a rocket, guided missile or aircraft*Pyrometric cone, pyrometric devices that are used to gauge time and temperature during the firing of ceramic materials*Roller cone bit, a drill bit used for drilling through rock, for example when drilling for oil and gas*Skid cone, a hollow steel or plastic cone placed over the sawn end of a log*Speaker cone, the cone inside a loudspeaker that moves to generate sound*Spinning cone columns are used in a form of steam distillation to gently extract volatile chemicals from liquid foodstuffs" ], [ "Biology and medicine", "*Cone cell, in anatomy, a type of light-sensitive cell found along with rods in the retina of the eye*Cone dystrophy, an inherited ocular disorder characterized by the loss of cone cells*Cone snail, a carnivorous mollusc of the family Conidae*Cone-billed tanager (''Conothraupis mesoleuca''), a species of bird in the family Thraupidae*Conifer cone, a seed-bearing organ on conifer plants*Growth cone, a dynamic, actin-supported extension of a developing axon seeking its synaptic target*Witch-hazel cone gall aphid (''Hormaphis hamamelidis''), a minuscule insect, a member of the aphid superfamily*Coning, a brain herniation in which the cerebellar tonsils move downwards through the foramen magnum" ], [ "Geography", "*Cinder cone, a steep conical hill of volcanic fragments around and downwind from a volcanic vent*Cone (hill), a hill in the shape of a cone which may or may not be volcanic in origin*Dirt cone, a feature of a glacier or snow patch, in which dirt forms a coating insulating the ice below*Parasitic cone (or satellite cone), a geographical feature found around a volcano*Shatter cone, rare geological feature in the bedrock beneath meteorite impact craters or underground nuclear explosions*Volcanic cone, among the simplest volcanic formations in the world*Lambert conformal conic projection (LCC), a conic map projection, which is often used for aeronautical charts" ], [ "Places", "*Cone (Phrygia), a town and bishopric of ancient Phrygia*Cone, Michigan, an unincorporated community in Michigan*Cone, Texas, an unincorporated community in Crosby County, Texas, United States*Cone Islet, a small granite island in south-eastern Australia*Conical Range, a small mountain range in southwestern British Columbia, Canada, between Seymour Inlet and Belize Inlet" ], [ "People", "*Bonnie Ethel Cone (1907–2003), American educator and founder of the University of North Carolina at Charlotte*Carin Cone (born 1940), American swimmer, Olympic medalist, world record holder, and gold medal winner from the Pan American Games*Chadrick Cone (born 1983), American football wide receiver for the Georgia Force in the Arena Football League*Cindy Parlow Cone (born 1978), American soccer player and coach*Cone sisters, Claribel Cone (1864–1929), and Etta Cone (1870–1949), collectors and socialites*David Cone (born 1963), former Major League Baseball pitcher*Edward T. Cone (1917–2004), American music theorist and composer*Fairfax M. Cone (1903–1977), director of the American Association of Advertising Agencies*Fred Cone (baseball) (1848–1909), pioneer professional baseball player*Fred Cone (American football) (1926–2021), former professional American football running back*Fred P. Cone (1871–1948), twenty-seventh governor of Florida (Frederick Preston)*Jason McCaslin (born 1980), nicknamed Cone, bassist for the Canadian band Sum 41*James Hal Cone (1938–2018), advocate of Black liberation theology*John Cone (born 1974), American professional wrestling referee*John J. Cone, the fourth Supreme Knight of the Knights of Columbus from 1898 to 1899*Mac Cone (born 1952), Canadian show jumper*Martin Cone (1882–1963), 6th president of St. Ambrose College from 1930 to 1937*Marvin Cone (1891–1965), American painter*Reuben Cone (1788–1851), pioneer and landowner in Atlanta, Georgia*Robert W. Cone (1957-2016), major general in the United States Army, and Special Assistant to the Commanding General of TRADOC*Sara Cone Bryant (1873–?", "), author of various children's book in the early 20th century*Spencer Cone Jones (1836–1915), President of the Maryland State Senate, Mayor of Rockville, Maryland*Spencer Houghton Cone (1785–1855), American Baptist minister and president of the American and Foreign Bible Society*Tim Cone (born 1957), American basketball coach" ], [ "Other uses", "*Conical Asian hat, a simple style of straw hat originating in East and Southeast Asia*Ice cream cone, an edible container in which ice cream is served, shaped like an inverted cone open at its top*Snow cone, a dessert usually made of crushed or shaved ice, flavored with sweet, usually fruit-flavored, brightly colored syrup*Traffic cone, a brightly colored cone-shaped plastic object commonly used as a temporary traffic barrier or warning sign*USS ''Cone'' (DD-866), a ''Gearing''-class destroyer of the United States Navy*Elizabethan collar or e-collar, a device to keep an animal from licking or biting itself*To locate an aircraft using a searchlight*Cone Mills Corporation, a textile manufacturer" ], [ "See also", "***Kone (disambiguation)*Colne (disambiguation) (pronounced ''cone'')*Kegel (disambiguation) (German/Dutch translation of cone)" ] ]

[ [ "Chemical equilibrium" ], [ "Introduction", "In a chemical reaction, '''chemical equilibrium''' is the state in which both the reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the system.", "This state results when the forward reaction proceeds at the same rate as the reverse reaction.", "The reaction rates of the forward and backward reactions are generally not zero, but they are equal.", "Thus, there are no net changes in the concentrations of the reactants and products.", "Such a state is known as dynamic equilibrium." ], [ "Historical introduction", "The concept of chemical equilibrium was developed in 1803, after Berthollet found that some chemical reactions are reversible.", "For any reaction mixture to exist at equilibrium, the rates of the forward and backward (reverse) reactions must be equal.", "In the following chemical equation, arrows point both ways to indicate equilibrium.", "A and B are reactant chemical species, S and T are product species, and ''α'', ''β'', ''σ'', and ''τ'' are the stoichiometric coefficients of the respective reactants and products::''α'' A + ''β'' B ''σ'' S + ''τ'' TThe equilibrium concentration position of a reaction is said to lie \"far to the right\" if, at equilibrium, nearly all the reactants are consumed.", "Conversely the equilibrium position is said to be \"far to the left\" if hardly any product is formed from the reactants.Guldberg and Waage (1865), building on Berthollet's ideas, proposed the law of mass action::where A, B, S and T are active masses and ''k''+ and ''k''− are rate constants.", "Since at equilibrium forward and backward rates are equal::and the ratio of the rate constants is also a constant, now known as an equilibrium constant.", ":By convention, the products form the numerator.However, the law of mass action is valid only for concerted one-step reactions that proceed through a single transition state and is '''not valid in general''' because rate equations do not, in general, follow the stoichiometry of the reaction as Guldberg and Waage had proposed (see, for example, nucleophilic aliphatic substitution by SN1 or reaction of hydrogen and bromine to form hydrogen bromide).", "Equality of forward and backward reaction rates, however, is a necessary condition for chemical equilibrium, though it is not sufficient to explain why equilibrium occurs.Despite the limitations of this derivation, the equilibrium constant for a reaction is indeed a constant, independent of the activities of the various species involved, though it does depend on temperature as observed by the van 't Hoff equation.", "Adding a catalyst will affect both the forward reaction and the reverse reaction in the same way and will not have an effect on the equilibrium constant.", "The catalyst will speed up both reactions thereby increasing the speed at which equilibrium is reached.Although the macroscopic equilibrium concentrations are constant in time, reactions do occur at the molecular level.", "For example, in the case of acetic acid dissolved in water and forming acetate and hydronium ions,:a proton may hop from one molecule of acetic acid onto a water molecule and then onto an acetate anion to form another molecule of acetic acid and leaving the number of acetic acid molecules unchanged.", "This is an example of dynamic equilibrium.", "Equilibria, like the rest of thermodynamics, are statistical phenomena, averages of microscopic behavior.", "'''Le Châtelier's principle''' (1884) predicts the behavior of an equilibrium system when changes to its reaction conditions occur.", "''If a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to partially reverse the change''.", "For example, adding more S (to the chemical reaction above) from the outside will cause an excess of products, and the system will try to counteract this by increasing the reverse reaction and pushing the equilibrium point backward (though the equilibrium constant will stay the same).If mineral acid is added to the acetic acid mixture, increasing the concentration of hydronium ion, the amount of dissociation must decrease as the reaction is driven to the left in accordance with this principle.", "This can also be deduced from the equilibrium constant expression for the reaction::If {H3O+} increases {CH3CO2H} must increase and must decrease.", "The H2O is left out, as it is the solvent and its concentration remains high and nearly constant.A quantitative version is given by the reaction quotient.J.", "W. Gibbs suggested in 1873 that equilibrium is attained when the Gibbs free energy of the system is at its minimum value (assuming the reaction is carried out at a constant temperature and pressure).", "What this means is that the derivative of the Gibbs energy with respect to reaction coordinate (a measure of the extent of reaction that has occurred, ranging from zero for all reactants to a maximum for all products) vanishes (because dG = 0), signaling a stationary point.", "This derivative is called the reaction Gibbs energy (or energy change) and corresponds to the difference between the chemical potentials of reactants and products at the composition of the reaction mixture.", "This criterion is both necessary and sufficient.", "If a mixture is not at equilibrium, the liberation of the excess Gibbs energy (or Helmholtz energy at constant volume reactions) is the \"driving force\" for the composition of the mixture to change until equilibrium is reached.", "The equilibrium constant can be related to the standard Gibbs free energy change for the reaction by the equation:where ''R'' is the universal gas constant and ''T'' the temperature.When the reactants are dissolved in a medium of high ionic strength the quotient of activity coefficients may be taken to be constant.", "In that case the '''concentration quotient''', ''K''c,:where A is the concentration of A, etc., is independent of the analytical concentration of the reactants.", "For this reason, equilibrium constants for solutions are usually determined in media of high ionic strength.", "''Kc'' varies with ionic strength, temperature and pressure (or volume).", "Likewise ''Kp'' for gases depends on partial pressure.", "These constants are easier to measure and encountered in high-school chemistry courses." ], [ "Thermodynamics", "At constant temperature and pressure, one must consider the Gibbs free energy, ''G'', while at constant temperature and volume, one must consider the Helmholtz free energy, ''A'', for the reaction; and at constant internal energy and volume, one must consider the entropy, ''S'', for the reaction.The constant volume case is important in geochemistry and atmospheric chemistry where pressure variations are significant.", "Note that, if reactants and products were in standard state (completely pure), then there would be no reversibility and no equilibrium.", "Indeed, they would necessarily occupy disjoint volumes of space.", "The mixing of the products and reactants contributes a large entropy increase (known as entropy of mixing) to states containing equal mixture of products and reactants and gives rise to a distinctive minimum in the Gibbs energy as a function of the extent of reaction.", "The standard Gibbs energy change, together with the Gibbs energy of mixing, determine the equilibrium state.In this article only the '''constant pressure''' case is considered.", "The relation between the Gibbs free energy and the equilibrium constant can be found by considering chemical potentials.At constant temperature and pressure in the absence of an applied voltage, the Gibbs free energy, ''G'', for the reaction depends only on the extent of reaction: ''ξ'' (Greek letter xi), and can only decrease according to the second law of thermodynamics.", "It means that the derivative of ''G'' with respect to ''ξ'' must be negative if the reaction happens; at the equilibrium this derivative is equal to zero.", "::equilibriumIn order to meet the thermodynamic condition for equilibrium, the Gibbs energy must be stationary, meaning that the derivative of ''G'' with respect to the extent of reaction, ''ξ'', must be zero.", "It can be shown that in this case, the sum of chemical potentials times the stoichiometric coefficients of the products is equal to the sum of those corresponding to the reactants.", "Therefore, the sum of the Gibbs energies of the reactants must be the equal to the sum of the Gibbs energies of the products.", ":where ''μ'' is in this case a partial molar Gibbs energy, a chemical potential.", "The chemical potential of a reagent A is a function of the activity, {A} of that reagent.", ":(where ''μ'' is the '''standard chemical potential''').The definition of the Gibbs energy equation interacts with the fundamental thermodynamic relation to produce:.Inserting ''dNi'' = ''νi dξ'' into the above equation gives a stoichiometric coefficient () and a differential that denotes the reaction occurring to an infinitesimal extent (''dξ'').", "At constant pressure and temperature the above equations can be written as: which is the \"Gibbs free energy change for the reaction'''.", "This results in::.By substituting the chemical potentials::,the relationship becomes::::which is the '''standard Gibbs energy change for the reaction''' that can be calculated using thermodynamical tables.The reaction quotient is defined as::Therefore,:At equilibrium::leading to::and:Obtaining the value of the standard Gibbs energy change, allows the calculation of the equilibrium constant.right===Addition of reactants or products===For a reactional system at equilibrium: ''Q''r = ''K''eq; ''ξ'' = ''ξ''eq.", "*If the activities of constituents are modified, the value of the reaction quotient changes and becomes different from the equilibrium constant: ''Q''r ≠ ''K''eq and then *If activity of a reagent ''i'' increases the reaction quotient decreases.", "Then and The reaction will shift to the right (i.e.", "in the forward direction, and thus more products will form).", "*If activity of a product ''j'' increases, then and The reaction will shift to the left (i.e.", "in the reverse direction, and thus less products will form).Note that activities and equilibrium constants are dimensionless numbers.===Treatment of activity===The expression for the equilibrium constant can be rewritten as the product of a concentration quotient, ''K''c and an activity coefficient quotient, ''Γ''.", ":A is the concentration of reagent A, etc.", "It is possible in principle to obtain values of the activity coefficients, γ.", "For solutions, equations such as the Debye–Hückel equation or extensions such as Davies equation Specific ion interaction theory or Pitzer equations may be used.Software (below) However this is not always possible.", "It is common practice to assume that ''Γ'' is a constant, and to use the concentration quotient in place of the thermodynamic equilibrium constant.", "It is also general practice to use the term ''equilibrium constant'' instead of the more accurate ''concentration quotient''.", "This practice will be followed here.For reactions in the gas phase partial pressure is used in place of concentration and fugacity coefficient in place of activity coefficient.", "In the real world, for example, when making ammonia in industry, fugacity coefficients must be taken into account.", "Fugacity, ''f'', is the product of partial pressure and fugacity coefficient.", "The chemical potential of a species in the real gas phase is given by:so the general expression defining an equilibrium constant is valid for both solution and gas phases.===Concentration quotients===In aqueous solution, equilibrium constants are usually determined in the presence of an \"inert\" electrolyte such as sodium nitrate, NaNO3, or potassium perchlorate, KClO4.The ionic strength of a solution is given by:where ''ci'' and ''zi'' stand for the concentration and ionic charge of ion type ''i'', and the sum is taken over all the ''N'' types of charged species in solution.", "When the concentration of dissolved salt is much higher than the analytical concentrations of the reagents, the ions originating from the dissolved salt determine the ionic strength, and the ionic strength is effectively constant.", "Since activity coefficients depend on ionic strength, the activity coefficients of the species are effectively independent of concentration.", "Thus, the assumption that ''Γ'' is constant is justified.", "The concentration quotient is a simple multiple of the equilibrium constant.", ":However, ''K''c will vary with ionic strength.", "If it is measured at a series of different ionic strengths, the value can be extrapolated to zero ionic strength.", "The concentration quotient obtained in this manner is known, paradoxically, as a thermodynamic equilibrium constant.Before using a published value of an equilibrium constant in conditions of ionic strength different from the conditions used in its determination, the value should be adjustedSoftware (below).===Metastable mixtures===A mixture may appear to have no tendency to change, though it is not at equilibrium.", "For example, a mixture of SO2 and O2 is metastable as there is a kinetic barrier to formation of the product, SO3.", ":2 SO2 + O2 2 SO3The barrier can be overcome when a catalyst is also present in the mixture as in the contact process, but the catalyst does not affect the equilibrium concentrations.Likewise, the formation of bicarbonate from carbon dioxide and water is very slow under normal conditions:but almost instantaneous in the presence of the catalytic enzyme carbonic anhydrase." ], [ "Pure substances", "When pure substances (liquids or solids) are involved in equilibria their activities do not appear in the equilibrium constant because their numerical values are considered one.Applying the general formula for an equilibrium constant to the specific case of a dilute solution of acetic acid in water one obtains:CH3CO2H + H2O CH3CO2− + H3O+:For all but very concentrated solutions, the water can be considered a \"pure\" liquid, and therefore it has an activity of one.", "The equilibrium constant expression is therefore usually written as:.A particular case is the self-ionization of water:2 H2O H3O+ + OH−Because water is the solvent, and has an activity of one, the self-ionization constant of water is defined as:It is perfectly legitimate to write H+ for the hydronium ion concentration, since the state of solvation of the proton is constant (in dilute solutions) and so does not affect the equilibrium concentrations.", "''K''w varies with variation in ionic strength and/or temperature.The concentrations of H+ and OH− are not independent quantities.", "Most commonly OH− is replaced by ''K''wH+−1 in equilibrium constant expressions which would otherwise include hydroxide ion.Solids also do not appear in the equilibrium constant expression, if they are considered to be pure and thus their activities taken to be one.", "An example is the Boudouard reaction::2 CO CO2 + Cfor which the equation (without solid carbon) is written as::" ], [ "Multiple equilibria", "Consider the case of a dibasic acid H2A.", "When dissolved in water, the mixture will contain H2A, HA− and A2−.", "This equilibrium can be split into two steps in each of which one proton is liberated.", ":''K''1 and'' K''2 are examples of ''stepwise'' equilibrium constants.", "The ''overall'' equilibrium constant, ''β''D, is product of the stepwise constants.", ":{H2A} {A^{2-}} + {2H+}:Note that these constants are dissociation constants because the products on the right hand side of the equilibrium expression are dissociation products.", "In many systems, it is preferable to use association constants.", ":''β''1 and ''β''2 are examples of association constants.", "Clearly and ; and For multiple equilibrium systems, also see: theory of Response reactions." ], [ "Effect of temperature", "The effect of changing temperature on an equilibrium constant is given by the van 't Hoff equation:Thus, for exothermic reactions (Δ''H'' is negative), ''K'' decreases with an increase in temperature, but, for endothermic reactions, (ΔH is positive) ''K'' increases with an increase temperature.", "An alternative formulation is:At first sight this appears to offer a means of obtaining the standard molar enthalpy of the reaction by studying the variation of ''K'' with temperature.", "In practice, however, the method is unreliable because error propagation almost always gives very large errors on the values calculated in this way." ], [ "Effect of electric and magnetic fields", "The effect of electric field on equilibrium has been studied by Manfred Eigen among others." ], [ "Types of equilibrium", "Equilibrium can be broadly classified as heterogeneous and homogeneous equilibrium.", "Homogeneous equilibrium consists of reactants and products belonging in the same phase whereas heterogeneous equilibrium comes into play for reactants and products in different phases.", "* In the gas phase: rocket engines* The industrial synthesis such as ammonia in the Haber–Bosch process (depicted right) takes place through a succession of equilibrium steps including adsorption processes* Atmospheric chemistry* Seawater and other natural waters: chemical oceanography* Distribution between two phases** log ''D'' distribution coefficient: important for pharmaceuticals where lipophilicity is a significant property of a drug** Liquid–liquid extraction, Ion exchange, Chromatography** Solubility product** Uptake and release of oxygen by hemoglobin in blood* Acid–base equilibria: acid dissociation constant, hydrolysis, buffer solutions, indicators, acid–base homeostasis* Metal–ligand complexation: sequestering agents, chelation therapy, MRI contrast reagents, Schlenk equilibrium* Adduct formation: host–guest chemistry, supramolecular chemistry, molecular recognition, dinitrogen tetroxide* In certain oscillating reactions, the approach to equilibrium is not asymptotically but in the form of a damped oscillation .", "* The related Nernst equation in electrochemistry gives the difference in electrode potential as a function of redox concentrations.", "* When molecules on each side of the equilibrium are able to further react irreversibly in secondary reactions, the final product ratio is determined according to the Curtin–Hammett principle.In these applications, terms such as stability constant, formation constant, binding constant, affinity constant, association constant and dissociation constant are used.", "In biochemistry, it is common to give units for binding constants, which serve to define the concentration units used when the constant's value was determined." ], [ "Composition of a mixture", "When the only equilibrium is that of the formation of a 1:1 adduct as the composition of a mixture, there are many ways that the composition of a mixture can be calculated.", "For example, see ICE table for a traditional method of calculating the pH of a solution of a weak acid.There are three approaches to the general calculation of the composition of a mixture at equilibrium.#The most basic approach is to manipulate the various equilibrium constants until the desired concentrations are expressed in terms of measured equilibrium constants (equivalent to measuring chemical potentials) and initial conditions.#Minimize the Gibbs energy of the system.# Satisfy the equation of mass balance.", "The equations of mass balance are simply statements that demonstrate that the total concentration of each reactant must be constant by the law of conservation of mass.===Mass-balance equations===In general, the calculations are rather complicated or complex.", "For instance, in the case of a dibasic acid, H2A dissolved in water the two reactants can be specified as the conjugate base, A2−, and the proton, H+.", "The following equations of mass-balance could apply equally well to a base such as 1,2-diaminoethane, in which case the base itself is designated as the reactant A:::with TA the total concentration of species A.", "Note that it is customary to omit the ionic charges when writing and using these equations.When the equilibrium constants are known and the total concentrations are specified there are two equations in two unknown \"free concentrations\" A and H. This follows from the fact that HA = ''β''1AH, H2A = ''β''2AH2 and OH = ''K''wH−1::so the concentrations of the \"complexes\" are calculated from the free concentrations and the equilibrium constants.General expressions applicable to all systems with two reagents, A and B would be::It is easy to see how this can be extended to three or more reagents.====Polybasic acids====Species concentrations during hydrolysis of the aluminium.The composition of solutions containing reactants A and H is easy to calculate as a function of pH|pH.", "When H is known, the free concentration A is calculated from the mass-balance equation in A.The diagram alongside, shows an example of the hydrolysis of the aluminium Lewis acid Al3+(aq) shows the species concentrations for a 5 × 10−6 M solution of an aluminium salt as a function of pH.", "Each concentration is shown as a percentage of the total aluminium.====Solution and precipitation====The diagram above illustrates the point that a precipitate that is not one of the main species in the solution equilibrium may be formed.", "At pH just below 5.5 the main species present in a 5 μM solution of Al3+ are aluminium hydroxides Al(OH)2+, and , but on raising the pH Al(OH)3 precipitates from the solution.", "This occurs because Al(OH)3 has a very large lattice energy.", "As the pH rises more and more Al(OH)3 comes out of solution.", "This is an example of Le Châtelier's principle in action: Increasing the concentration of the hydroxide ion causes more aluminium hydroxide to precipitate, which removes hydroxide from the solution.", "When the hydroxide concentration becomes sufficiently high the soluble aluminate, , is formed.Another common instance where precipitation occurs is when a metal cation interacts with an anionic ligand to form an electrically neutral complex.", "If the complex is hydrophobic, it will precipitate out of water.", "This occurs with the nickel ion Ni2+ and dimethylglyoxime, (dmgH2): in this case the lattice energy of the solid is not particularly large, but it greatly exceeds the energy of solvation of the molecule Ni(dmgH)2.===Minimization of Gibbs energy===At equilibrium, at a specified temperature and pressure, and with no external forces, the Gibbs free energy ''G'' is at a minimum::where μj is the chemical potential of molecular species ''j'', and ''Nj'' is the amount of molecular species ''j''.", "It may be expressed in terms of thermodynamic activity as::where is the chemical potential in the standard state, ''R'' is the gas constant ''T'' is the absolute temperature, and ''Aj'' is the activity.For a closed system, no particles may enter or leave, although they may combine in various ways.", "The total number of atoms of each element will remain constant.", "This means that the minimization above must be subjected to the constraints::where ''aij'' is the number of atoms of element ''i'' in molecule ''j'' and ''b'' is the total number of atoms of element ''i'', which is a constant, since the system is closed.", "If there are a total of ''k'' types of atoms in the system, then there will be ''k'' such equations.", "If ions are involved, an additional row is added to the aij matrix specifying the respective charge on each molecule which will sum to zero.This is a standard problem in optimisation, known as constrained minimisation.", "The most common method of solving it is using the method of Lagrange multipliers (although other methods may be used).Define::where the ''λi'' are the Lagrange multipliers, one for each element.", "This allows each of the ''Nj'' and ''λj'' to be treated independently, and it can be shown using the tools of multivariate calculus that the equilibrium condition is given by::(For proof see Lagrange multipliers.)", "This is a set of (''m'' + ''k'') equations in (''m'' + ''k'') unknowns (the ''Nj'' and the ''λi'') and may, therefore, be solved for the equilibrium concentrations ''Nj'' as long as the chemical activities are known as functions of the concentrations at the given temperature and pressure.", "(In the ideal case, activities are proportional to concentrations.)", "(See Thermodynamic databases for pure substances.)", "Note that the second equation is just the initial constraints for minimization.This method of calculating equilibrium chemical concentrations is useful for systems with a large number of different molecules.", "The use of ''k'' atomic element conservation equations for the mass constraint is straightforward, and replaces the use of the stoichiometric coefficient equations.", "The results are consistent with those specified by chemical equations.", "For example, if equilibrium is specified by a single chemical equation:,:where νj is the stoichiometric coefficient for the ''j'' th molecule (negative for reactants, positive for products) and ''Rj'' is the symbol for the ''j'' th molecule, a properly balanced equation will obey::Multiplying the first equilibrium condition by νj and using the above equation yields::As above, defining ΔG:where ''Kc'' is the equilibrium constant, and ΔG will be zero at equilibrium.Analogous procedures exist for the minimization of other thermodynamic potentials." ], [ "See also", "* Acidosis* Alkalosis* Arterial blood gas* Benesi–Hildebrand method* Determination of equilibrium constants* Equilibrium constant* Henderson–Hasselbalch equation* Mass-action ratio* Michaelis–Menten kinetics* pCO2* pH* p''K''a* Redox equilibria* Steady state (chemistry)* Thermodynamic databases for pure substances* Non-random two-liquid model (NRTL model) – Phase equilibrium calculations* UNIQUAC model – Phase equilibrium calculations" ], [ "References" ], [ "Further reading", "* Mainly concerned with gas-phase equilibria.", "**" ], [ "External links", "*" ] ]

[ [ "Combination" ], [ "Introduction", "In mathematics, a '''combination''' is a selection of items from a set that has distinct members, such that the order of selection does not matter (unlike permutations).", "For example, given three fruits, say an apple, an orange and a pear, there are three combinations of two that can be drawn from this set: an apple and a pear; an apple and an orange; or a pear and an orange.", "More formally, a ''k''-combination of a set ''S'' is a subset of ''k'' distinct elements of ''S''.", "So, two combinations are identical if and only if each combination has the same members.", "(The arrangement of the members in each set does not matter.)", "If the set has ''n'' elements, the number of ''k''-combinations, denoted by or , is equal to the binomial coefficientwhich can be written using factorials as whenever , and which is zero when .", "This formula can be derived from the fact that each ''k''-combination of a set ''S'' of ''n'' members has permutations so or .", "The set of all ''k''-combinations of a set ''S'' is often denoted by .A combination is a combination of ''n'' things taken ''k'' at a time ''without repetition''.", "To refer to combinations in which repetition is allowed, the terms ''k''-combination with repetition, ''k''-multiset, or ''k''-selection, are often used.", "If, in the above example, it were possible to have two of any one kind of fruit there would be 3 more 2-selections: one with two apples, one with two oranges, and one with two pears.Although the set of three fruits was small enough to write a complete list of combinations, this becomes impractical as the size of the set increases.", "For example, a poker hand can be described as a 5-combination (''k'' = 5) of cards from a 52 card deck (''n'' = 52).", "The 5 cards of the hand are all distinct, and the order of cards in the hand does not matter.", "There are 2,598,960 such combinations, and the chance of drawing any one hand at random is 1 / 2,598,960." ], [ "Number of ''k''-combinations", "3-element subsets of a 5-element setThe number of ''k''-combinations from a given set ''S'' of ''n'' elements is often denoted in elementary combinatorics texts by , or by a variation such as , , , or even (the last form is standard in French, Romanian, Russian, Chinese and Polish texts).", "The same number however occurs in many other mathematical contexts, where it is denoted by (often read as \"''n'' choose ''k''\"); notably it occurs as a coefficient in the binomial formula, hence its name binomial coefficient.", "One can define for all natural numbers ''k'' at once by the relationfrom which it is clear thatand furtherfor ''k'' > ''n''.To see that these coefficients count ''k''-combinations from ''S'', one can first consider a collection of ''n'' distinct variables ''X''''s'' labeled by the elements ''s'' of ''S'', and expand the product over all elements of ''S'':it has 2''n'' distinct terms corresponding to all the subsets of ''S'', each subset giving the product of the corresponding variables ''X''''s''.", "Now setting all of the ''X''''s'' equal to the unlabeled variable ''X'', so that the product becomes , the term for each ''k''-combination from ''S'' becomes ''X''''k'', so that the coefficient of that power in the result equals the number of such ''k''-combinations.Binomial coefficients can be computed explicitly in various ways.", "To get all of them for the expansions up to , one can use (in addition to the basic cases already given) the recursion relationfor 0 ''n''.", "Choose those numbers having ''k'' nonzero bits, although this is very inefficient even for small ''n'' (e.g.", "''n'' = 20 would require visiting about one million numbers while the maximum number of allowed ''k'' combinations is about 186 thousand for ''k'' = 10).", "The positions of these 1 bits in such a number is a specific ''k''-combination of the set { 1, ..., ''n'' }.", "Another simple, faster way is to track ''k'' index numbers of the elements selected, starting with {0 .. ''k''−1} (zero-based) or {1 .. ''k''} (one-based) as the first allowed ''k''-combination and then repeatedly moving to the next allowed ''k''-combination by incrementing the last index number if it is lower than ''n''-1 (zero-based) or ''n'' (one-based) or the last index number ''x'' that is less than the index number following it minus one if such an index exists and resetting the index numbers after ''x'' to {''x''+1, ''x''+2, ...}." ], [ "Number of combinations with repetition", "A ''k''-'''combination with repetitions''', or ''k''-'''multicombination''', or '''multisubset''' of size ''k'' from a set ''S'' of size ''n'' is given by a set of ''k'' not necessarily distinct elements of ''S'', where order is not taken into account: two sequences define the same multiset if one can be obtained from the other by permuting the terms.", "In other words, it is a sample of ''k'' elements from a set of ''n'' elements allowing for duplicates (i.e., with replacement) but disregarding different orderings (e.g.", "{2,1,2} = {1,2,2}).", "Associate an index to each element of ''S'' and think of the elements of ''S'' as ''types'' of objects, then we can let denote the number of elements of type ''i'' in a multisubset.", "The number of multisubsets of size ''k'' is then the number of nonnegative integer (so allowing zero) solutions of the Diophantine equation:If ''S'' has ''n'' elements, the number of such ''k''-multisubsets is denoted bya notation that is analogous to the binomial coefficient which counts ''k''-subsets.", "This expression, ''n'' multichoose ''k'', can also be given in terms of binomial coefficients:This relationship can be easily proved using a representation known as stars and bars.", "A solution of the above Diophantine equation can be represented by ''stars'', a separator (a ''bar''), then more stars, another separator, and so on.", "The total number of stars in this representation is ''k'' and the number of bars is ''n'' - 1 (since a separation into n parts needs n-1 separators).", "Thus, a string of ''k'' + ''n'' - 1 (or ''n'' + ''k'' - 1) symbols (stars and bars) corresponds to a solution if there are ''k'' stars in the string.", "Any solution can be represented by choosing ''k'' out of positions to place stars and filling the remaining positions with bars.", "For example, the solution of the equation (''n'' = 4 and ''k'' = 10) can be represented byThe number of such strings is the number of ways to place 10 stars in 13 positions, which is the number of 10-multisubsets of a set with 4 elements.Bijection between 3-subsets of a 7-set (left) and 3-multisets with elements from a 5-set (right).This illustrates that .As with binomial coefficients, there are several relationships between these multichoose expressions.", "For example, for ,This identity follows from interchanging the stars and bars in the above representation.=== Example of counting multisubsets ===For example, if you have four types of donuts (''n'' = 4) on a menu to choose from and you want three donuts (''k'' = 3), the number of ways to choose the donuts with repetition can be calculated asThis result can be verified by listing all the 3-multisubsets of the set ''S'' = {1,2,3,4}.", "This is displayed in the following table.", "The second column lists the donuts you actually chose, the third column shows the nonnegative integer solutions of the equation and the last column gives the stars and bars representation of the solutions.", "No.", "3-multiset Eq.", "solution Stars and bars 1 {1,1,1} 3,0,0,0 2 {1,1,2} 2,1,0,0 3 {1,1,3} 2,0,1,0 4 {1,1,4} 2,0,0,1 5 {1,2,2} 1,2,0,0 6 {1,2,3} 1,1,1,0 7 {1,2,4} 1,1,0,1 8 {1,3,3} 1,0,2,0 9 {1,3,4} 1,0,1,1 10 {1,4,4} 1,0,0,2 11 {2,2,2} 0,3,0,0 12 {2,2,3} 0,2,1,0 13 {2,2,4} 0,2,0,1 14 {2,3,3} 0,1,2,0 15 {2,3,4} 0,1,1,1 16 {2,4,4} 0,1,0,2 17 {3,3,3} 0,0,3,0 18 {3,3,4} 0,0,2,1 19 {3,4,4} 0,0,1,2 20 {4,4,4} 0,0,0,3" ], [ "Number of ''k''-combinations for all ''k''", "The number of ''k''-combinations for all ''k'' is the number of subsets of a set of ''n'' elements.", "There are several ways to see that this number is 2''n''.", "In terms of combinations, , which is the sum of the ''n''th row (counting from 0) of the binomial coefficients in Pascal's triangle.", "These combinations (subsets) are enumerated by the 1 digits of the set of base 2 numbers counting from 0 to 2''n'' − 1, where each digit position is an item from the set of ''n''.Given 3 cards numbered 1 to 3, there are 8 distinct combinations (subsets), including the empty set:Representing these subsets (in the same order) as base 2 numerals:*0 – 000*1 – 001*2 – 010*3 – 011*4 – 100*5 – 101*6 – 110*7 – 111" ], [ "Probability: sampling a random combination", "There are various algorithms to pick out a random combination from a given set or list.", "Rejection sampling is extremely slow for large sample sizes.", "One way to select a ''k''-combination efficiently from a population of size ''n'' is to iterate across each element of the population, and at each step pick that element with a dynamically changing probability of (see Reservoir sampling).", "Another is to pick a random non-negative integer less than and convert it into a combination using the combinatorial number system." ], [ "Number of ways to put objects into bins", "A combination can also be thought of as a selection of ''two'' sets of items: those that go into the chosen bin and those that go into the unchosen bin.", "This can be generalized to any number of bins with the constraint that every item must go to exactly one bin.", "The number of ways to put objects into bins is given by the multinomial coefficientwhere ''n'' is the number of items, ''m'' is the number of bins, and is the number of items that go into bin ''i''.One way to see why this equation holds is to first number the objects arbitrarily from ''1'' to ''n'' and put the objects with numbers into the first bin in order, the objects with numbers into the second bin in order, and so on.", "There are distinct numberings, but many of them are equivalent, because only the set of items in a bin matters, not their order in it.", "Every combined permutation of each bins' contents produces an equivalent way of putting items into bins.", "As a result, every equivalence class consists of distinct numberings, and the number of equivalence classes is .The binomial coefficient is the special case where ''k'' items go into the chosen bin and the remaining items go into the unchosen bin:" ], [ "See also", "* Binomial coefficient* Combinatorics* Block design* Kneser graph* List of permutation topics* Multiset* Pascal's triangle* Permutation* Probability* Subset" ], [ "Notes" ], [ "References", "* * * Erwin Kreyszig, ''Advanced Engineering Mathematics'', John Wiley & Sons, INC, 1999.", "* * *" ], [ "External links", "* Topcoder tutorial on combinatorics * C code to generate all combinations of n elements chosen as k* Many Common types of permutation and combination math problems, with detailed solutions* The Unknown Formula For combinations when choices can be repeated and order does ''not'' matter* Combinations with repetitions (by: Akshatha AG and Smitha B)* The dice roll with a given sum problem An application of the combinations with repetition to rolling multiple dice" ] ]

[ [ "Software" ], [ "Introduction", "user interacts with application software on a typical desktop computer.", "The application software layer interfaces with the operating system, which in turn communicates with the hardware.", "The arrows indicate information flow.", "'''Software''' is a collection of programs and data that tell a computer how to perform specific tasks.", "Software often includes associated software documentation.", "This is in contrast to hardware, from which the system is built and which actually performs the work.At the lowest programming level, executable code consists of machine language instructions supported by an individual processor—typically a central processing unit (CPU) or a graphics processing unit (GPU).", "Machine language consists of groups of binary values signifying processor instructions that change the state of the computer from its preceding state.", "For example, an instruction may change the value stored in a particular storage location in the computer—an effect that is not directly observable to the user.", "An instruction may also invoke one of many input or output operations, for example, displaying some text on a computer screen, causing state changes that should be visible to the user.", "The processor executes the instructions in the order they are provided, unless it is instructed to \"jump\" to a different instruction or is interrupted by the operating system.", ", most personal computers, smartphone devices, and servers have processors with multiple execution units, or multiple processors performing computation together, so computing has become a much more concurrent activity than in the past.The majority of software is written in high-level programming languages.", "They are easier and more efficient for programmers because they are closer to natural languages than machine languages.", "High-level languages are translated into machine language using a compiler, an interpreter, or a combination of the two.", "Software may also be written in a low-level assembly language that has a strong correspondence to the computer's machine language instructions and is translated into machine language using an assembler." ], [ "History", "An algorithm for what would have been the first piece of software was written by Ada Lovelace in the 19th century, for the planned Analytical Engine.", "She created proofs to show how the engine would calculate Bernoulli numbers.", "Because of the proofs and the algorithm, she is considered the first computer programmer.The first theory about software, prior to the creation of computers as we know them today, was proposed by Alan Turing in his 1936 essay, ''On Computable Numbers, with an Application to the Entscheidungsproblem'' (decision problem).", "This eventually led to the creation of the academic fields of computer science and software engineering; both fields study software and its creation.", "Computer science is the theoretical study of computer and software (Turing's essay is an example of computer science), whereas software engineering is the application of engineering principles to development of software.In 2000, Fred Shapiro, a librarian at the Yale Law School, published a letter revealing that John Wilder Tukey's 1958 paper \"The Teaching of Concrete Mathematics\" contained the earliest known usage of the term \"software\" found in a search of JSTOR's electronic archives, predating the ''Oxford English Dictionary'''s citation by two years.", "This led many to credit Tukey with coining the term, particularly in obituaries published that same year, although Tukey never claimed credit for any such coinage.", "In 1995, Paul Niquette claimed he had originally coined the term in October 1953, although he could not find any documents supporting his claim.", "The earliest known publication of the term \"software\" in an engineering context was in August 1953 by Richard R. Carhart, in a Rand Corporation Research Memorandum." ], [ "Types", "Blender, a free software programOn virtually all computer platforms, software can be grouped into a few broad categories.===Purpose, or domain of use===Based on the goal, computer software can be divided into:* '''Application software''' uses the computer system to perform special functions beyond the basic operation of the computer itself.", "There are many different types of application software because the range of tasks that can be performed with a modern computer is so large—see list of software.", "* '''System software''' manages hardware behaviour, as to provide basic functionalities that are required by users, or for other software to run properly, if at all.", "System software is also designed for providing a platform for running application software, and it includes the following:** '''Operating systems''' are essential collections of software that manage resources and provide common services for other software that runs \"on top\" of them.", "Supervisory programs, boot loaders, shells and window systems are core parts of operating systems.", "In practice, an operating system comes bundled with additional software (including application software) so that a user can potentially do some work with a computer that only has one operating system.", "** '''Device drivers''' operate or control a particular type of device that is attached to a computer.", "Each device needs at least one corresponding device driver; because a computer typically has at minimum at least one input device and at least one output device, a computer typically needs more than one device driver.", "** '''Utilities''' are computer programs designed to assist users in the maintenance and care of their computers.", "* '''Malicious software''', or '''malware''', is software that is developed to harm or disrupt computers.", "Malware is closely associated with computer-related crimes, though some malicious programs may have been designed as practical jokes.===Nature or domain of execution===* Desktop applications such as web browsers and Microsoft Office and LibreOffice and WordPerfect, as well as smartphone and tablet applications (called \"apps\").", "* JavaScript scripts are pieces of software traditionally embedded in web pages that are run directly inside the web browser when a web page is loaded without the need for a web browser plugin.", "Software written in other programming languages can also be run within the web browser if the software is either translated into JavaScript, or if a web browser plugin that supports that language is installed; the most common example of the latter is ActionScript scripts, which are supported by the Adobe Flash plugin.", "* Server software, including:** Web applications, which usually run on the web server and output dynamically generated web pages to web browsers, using e.g.", "PHP, Java, ASP.NET, or even JavaScript that runs on the server.", "In modern times these commonly include some JavaScript to be run in the web browser as well, in which case they typically run partly on the server, partly in the web browser.", "* Plugins and extensions are software that extends or modifies the functionality of another piece of software, and require that software be used in order to function.", "* Embedded software resides as firmware within embedded systems, devices dedicated to a single use or a few uses such as cars and televisions (although some embedded devices such as wireless chipsets can ''themselves'' be part of an ordinary, non-embedded computer system such as a PC or smartphone).", "In the embedded system context there is sometimes no clear distinction between the system software and the application software.", "However, some embedded systems run embedded operating systems, and these systems do retain the distinction between system software and application software (although typically there will only be one, fixed application which is always run).", "* Microcode is a special, relatively obscure type of embedded software which tells the processor ''itself'' how to execute machine code, so it is actually a lower level than machine code.", "It is typically proprietary to the processor manufacturer, and any necessary correctional microcode software updates are supplied by them to users (which is much cheaper than shipping replacement processor hardware).", "Thus an ordinary programmer would not expect to ever have to deal with it.===Programming tools===Programming tools are also software in the form of programs or applications that developers use to create, debug, maintain, or otherwise support software.Software is written in one or more programming languages; there are many programming languages in existence, and each has at least one implementation, each of which consists of its own set of programming tools.", "These tools may be relatively self-contained programs such as compilers, debuggers, interpreters, linkers, and text editors, that can be combined to accomplish a task; or they may form an integrated development environment (IDE), which combines much or all of the functionality of such self-contained tools.", "IDEs may do this by either invoking the relevant individual tools or by re-implementing their functionality in a new way.", "An IDE can make it easier to do specific tasks, such as searching in files in a particular project.", "Many programming language implementations provide the option of using both individual tools or an IDE." ], [ "Topics", "===Architecture===People who use modern general purpose computers (as opposed to embedded systems, analog computers and supercomputers) usually see three layers of software performing a variety of tasks: platform, application, and user software.", "* '''Platform software''': The platform includes the firmware, device drivers, an operating system, and typically a graphical user interface which, in total, allow a user to interact with the computer and its peripherals (associated equipment).", "Platform software often comes bundled with the computer.", "On a PC one will usually have the ability to change the platform software.", "* '''Application software''': Application software is what most people think of when they think of software.", "Typical examples include office suites and video games.", "Application software is often purchased separately from computer hardware.", "Sometimes applications are bundled with the computer, but that does not change the fact that they run as independent applications.", "Applications are usually independent programs from the operating system, though they are often tailored for specific platforms.", "Most users think of compilers, databases, and other \"system software\" as applications.", "* '''User-written software''': End-user development tailors systems to meet users' specific needs.", "User software includes spreadsheet templates and word processor templates.", "Even email filters are a kind of user software.", "Users create this software themselves and often overlook how important it is.", "Depending on how competently the user-written software has been integrated into default application packages, many users may not be aware of the distinction between the original packages, and what has been added by co-workers.===Execution===Computer software has to be \"loaded\" into the computer's storage (such as the hard drive or memory).", "Once the software has loaded, the computer is able to ''execute'' the software.", "This involves passing instructions from the application software, through the system software, to the hardware which ultimately receives the instruction as machine code.", "Each instruction causes the computer to carry out an operation—moving data, carrying out a computation, or altering the control flow of instructions.Data movement is typically from one place in memory to another.", "Sometimes it involves moving data between memory and registers which enable high-speed data access in the CPU.", "Moving data, especially large amounts of it, can be costly; this is sometimes avoided by using \"pointers\" to data instead.", "Computations include simple operations such as incrementing the value of a variable data element.", "More complex computations may involve many operations and data elements together.===Quality and reliability===Software quality is very important, especially for commercial and system software.", "If software is faulty, it can delete a person's work, crash the computer and do other unexpected things.", "Faults and errors are called \"bugs\" which are often discovered during alpha and beta testing.", "Software is often also a victim to what is known as software aging, the progressive performance degradation resulting from a combination of unseen bugs.Many bugs are discovered and fixed through software testing.", "However, software testing rarely—if ever—eliminates every bug; some programmers say that \"every program has at least one more bug\" (Lubarsky's Law).", "In the waterfall method of software development, separate testing teams are typically employed, but in newer approaches, collectively termed agile software development, developers often do all their own testing, and demonstrate the software to users/clients regularly to obtain feedback.", "Software can be tested through unit testing, regression testing and other methods, which are done manually, or most commonly, automatically, since the amount of code to be tested can be large.", "Programs containing command software enable hardware engineering and system operations to function much easier together.===License===The software's license gives the user the right to use the software in the licensed environment, and in the case of free software licenses, also grants other rights such as the right to make copies.Proprietary software can be divided into two types:* freeware, which includes the category of \"free trial\" software or \"freemium\" software (in the past, the term shareware was often used for free trial/freemium software).", "As the name suggests, freeware can be used for free, although in the case of free trials or freemium software, this is sometimes only true for a limited period of time or with limited functionality.", "* software available for a fee, which can only be legally used on purchase of a license.Open-source software comes with a free software license, granting the recipient the rights to modify and redistribute the software.===Patents===Software patents, like other types of patents, are theoretically supposed to give an inventor an exclusive, time-limited license for a ''detailed idea (e.g.", "an algorithm) on how to implement'' a piece of software, or a component of a piece of software.", "Ideas for useful things that software could ''do'', and user ''requirements'', are not supposed to be patentable, and concrete implementations (i.e.", "the actual software packages implementing the patent) are not supposed to be patentable either—the latter are already covered by copyright, generally automatically.", "So software patents are supposed to cover the middle area, between requirements and concrete implementation.", "In some countries, a requirement for the claimed invention to have an effect on the physical world may also be part of the requirements for a software patent to be held valid—although since ''all'' useful software has effects on the physical world, this requirement may be open to debate.", "Meanwhile, American copyright law was applied to various aspects of the writing of the software code.Software patents are controversial in the software industry with many people holding different views about them.", "One of the sources of controversy is that the aforementioned split between initial ideas and patent does not seem to be honored in practice by patent lawyers—for example the patent for aspect-oriented programming (AOP), which purported to claim rights over ''any'' programming tool implementing the idea of AOP, howsoever implemented.", "Another source of controversy is the effect on innovation, with many distinguished experts and companies arguing that software is such a fast-moving field that software patents merely create vast additional litigation costs and risks, and actually retard innovation.", "In the case of debates about software patents outside the United States, the argument has been made that large American corporations and patent lawyers are likely to be the primary beneficiaries of allowing or continue to allow software patents." ], [ "Design and implementation", "Design and implementation of software vary depending on the complexity of the software.", "For instance, the design and creation of Microsoft Word took much more time than designing and developing Microsoft Notepad because the former has much more basic functionality.Software is usually developed in integrated development environments (IDE) like Eclipse, IntelliJ and Microsoft Visual Studio that can simplify the process and compile the software.", "As noted in a different section, software is usually created on top of existing software and the application programming interface (API) that the underlying software provides like GTK+, JavaBeans or Swing.", "Libraries (APIs) can be categorized by their purpose.", "For instance, the Spring Framework is used for implementing enterprise applications, the Windows Forms library is used for designing graphical user interface (GUI) applications like Microsoft Word, and Windows Communication Foundation is used for designing web services.", "When a program is designed, it relies upon the API.", "For instance, a Microsoft Windows desktop application might call API functions in the .NET Windows Forms library like ''Form1.Close()'' and ''Form1.Show()'' to close or open the application.", "Without these APIs, the programmer needs to write these functionalities entirely themselves.", "Companies like Oracle and Microsoft provide their own APIs so that many applications are written using their software libraries that usually have numerous APIs in them.Data structures such as hash tables, arrays, and binary trees, and algorithms such as quicksort, can be useful for creating software.Computer software has special economic characteristics that make its design, creation, and distribution different from most other economic goods.A person who creates software is called a programmer, software engineer or software developer, terms that all have a similar meaning.", "More informal terms for programmer also exist such as \"coder\" and \"hacker\"although use of the latter word may cause confusion, because it is more often used to mean someone who illegally breaks into computer systems." ], [ "See also", "* Computer program* Independent software vendor* Open-source software* Outline of software* Software asset management* Software release life cycle" ], [ "References", "===Sources===*" ], [ "External links", "* Software at ''Encyclopædia Britannica''*" ] ]

[ [ "Computer programming" ], [ "Introduction", "'''Computer programming''' or '''coding''' is the composition of sequences of instructions, called programs, that computers can follow to perform tasks.", "It involves designing and implementing algorithms, step-by-step specifications of procedures, by writing code in one or more programming languages.", "Programmers typically use high-level programming languages that are more easily intelligible to humans than machine code, which is directly executed by the central processing unit.", "Proficient programming usually requires expertise in several different subjects, including knowledge of the application domain, details of programming languages and generic code libraries, specialized algorithms, and formal logic.Auxiliary tasks accompanying and related to programming include analyzing requirements, testing, debugging (investigating and fixing problems), implementation of build systems, and management of derived artifacts, such as programs' machine code.", "While these are sometimes considered programming, often the term ''software development'' is used for this larger overall process – with the terms ''programming'', ''implementation'', and ''coding'' reserved for the writing and editing of code per se.", "Sometimes software development is known as ''software engineering'', especially when it employs formal methods or follows an engineering design process." ], [ "History", "Ada Lovelace, whose notes added to the end of Luigi Menabrea's paper included the first algorithm designed for processing by an Analytical Engine.", "She is often recognized as history's first computer programmer.Programmable devices have existed for centuries.", "As early as the 9th century, a programmable music sequencer was invented by the Persian Banu Musa brothers, who described an automated mechanical flute player in the ''Book of Ingenious Devices''.", "In 1206, the Arab engineer Al-Jazari invented a programmable drum machine where a musical mechanical automaton could be made to play different rhythms and drum patterns, via pegs and cams.", "In 1801, the Jacquard loom could produce entirely different weaves by changing the \"program\" – a series of pasteboard cards with holes punched in them.Code-breaking algorithms have also existed for centuries.", "In the 9th century, the Arab mathematician Al-Kindi described a cryptographic algorithm for deciphering encrypted code, in ''A Manuscript on Deciphering Cryptographic Messages''.", "He gave the first description of cryptanalysis by frequency analysis, the earliest code-breaking algorithm.The first computer program is generally dated to 1843, when mathematician Ada Lovelace published an algorithm to calculate a sequence of Bernoulli numbers, intended to be carried out by Charles Babbage's Analytical Engine.", "However, Charles Babbage had already written his first program for the Analytical Engine in 1837.Data and instructions were once stored on external punched cards, which were kept in order and arranged in program decks.In the 1880s, Herman Hollerith invented the concept of storing ''data'' in machine-readable form.", "Later a control panel (plug board) added to his 1906 Type I Tabulator allowed it to be programmed for different jobs, and by the late 1940s, unit record equipment such as the IBM 602 and IBM 604, were programmed by control panels in a similar way, as were the first electronic computers.", "However, with the concept of the stored-program computer introduced in 1949, both programs and data were stored and manipulated in the same way in computer memory.===Machine language===Machine code was the language of early programs, written in the instruction set of the particular machine, often in binary notation.", "Assembly languages were soon developed that let the programmer specify instruction in a text format (e.g., ADD X, TOTAL), with abbreviations for each operation code and meaningful names for specifying addresses.", "However, because an assembly language is little more than a different notation for a machine language, two machines with different instruction sets also have different assembly languages.control panel for an IBM 402 Accounting Machine.", "Wires connect pulse streams from the card reader to counters and other internal logic and ultimately to the printer.===Compiler languages===High-level languages made the process of developing a program simpler and more understandable, and less bound to the underlying hardware.", "The first compiler related tool, the A-0 System, was developed in 1952 by Grace Hopper, who also coined the term 'compiler'.", "FORTRAN, the first widely used high-level language to have a functional implementation, came out in 1957, and many other languages were soon developed—in particular, COBOL aimed at commercial data processing, and Lisp for computer research.These compiled languages allow the programmer to write programs in terms that are syntactically richer, and more capable of abstracting the code, making it easy to target varying machine instruction sets via compilation declarations and heuristics.", "Compilers harnessed the power of computers to make programming easier by allowing programmers to specify calculations by entering a formula using infix notation.===Source code entry===Programs were mostly entered using punched cards or paper tape.", "By the late 1960s, data storage devices and computer terminals became inexpensive enough that programs could be created by typing directly into the computers.", "Text editors were also developed that allowed changes and corrections to be made much more easily than with punched cards." ], [ "Modern programming", "===Quality requirements===Whatever the approach to development may be, the final program must satisfy some fundamental properties.", "The following properties are among the most important:*Reliability: how often the results of a program are correct.", "This depends on conceptual correctness of algorithms and minimization of programming mistakes, such as mistakes in resource management (e.g., buffer overflows and race conditions) and logic errors (such as division by zero or off-by-one errors).", "*Robustness: how well a program anticipates problems due to errors (not bugs).", "This includes situations such as incorrect, inappropriate or corrupt data, unavailability of needed resources such as memory, operating system services, and network connections, user error, and unexpected power outages.", "*Usability: the ergonomics of a program: the ease with which a person can use the program for its intended purpose or in some cases even unanticipated purposes.", "Such issues can make or break its success even regardless of other issues.", "This involves a wide range of textual, graphical, and sometimes hardware elements that improve the clarity, intuitiveness, cohesiveness and completeness of a program's user interface.", "*Portability: the range of computer hardware and operating system platforms on which the source code of a program can be compiled/interpreted and run.", "This depends on differences in the programming facilities provided by the different platforms, including hardware and operating system resources, expected behavior of the hardware and operating system, and availability of platform-specific compilers (and sometimes libraries) for the language of the source code.", "*Maintainability: the ease with which a program can be modified by its present or future developers in order to make improvements or to customize, fix bugs and security holes, or adapt it to new environments.", "Good practices during initial development make the difference in this regard.", "This quality may not be directly apparent to the end user but it can significantly affect the fate of a program over the long term.", "*Efficiency/performance: Measure of system resources a program consumes (processor time, memory space, slow devices such as disks, network bandwidth and to some extent even user interaction): the less, the better.", "This also includes careful management of resources, for example cleaning up temporary files and eliminating memory leaks.", "This is often discussed under the shadow of a chosen programming language.", "Although the language certainly affects performance, even slower languages, such as Python, can execute programs instantly from a human perspective.", "Speed, resource usage, and performance are important for programs that bottleneck the system, but efficient use of programmer time is also important and is related to cost: more hardware may be cheaper.===Readability of source code===In computer programming, readability refers to the ease with which a human reader can comprehend the purpose, control flow, and operation of source code.", "It affects the aspects of quality above, including portability, usability and most importantly maintainability.Readability is important because programmers spend the majority of their time reading, trying to understand, reusing and modifying existing source code, rather than writing new source code.", "Unreadable code often leads to bugs, inefficiencies, and duplicated code.", "A study found that a few simple readability transformations made code shorter and drastically reduced the time to understand it.Following a consistent programming style often helps readability.", "However, readability is more than just programming style.", "Many factors, having little or nothing to do with the ability of the computer to efficiently compile and execute the code, contribute to readability.", "Some of these factors include:*Different indent styles (whitespace)*Comments*Decomposition*Naming conventions for objects (such as variables, classes, functions, procedures, etc.", ")The presentation aspects of this (such as indents, line breaks, color highlighting, and so on) are often handled by the source code editor, but the content aspects reflect the programmer's talent and skills.Various visual programming languages have also been developed with the intent to resolve readability concerns by adopting non-traditional approaches to code structure and display.", "Integrated development environments (IDEs) aim to integrate all such help.", "Techniques like Code refactoring can enhance readability.===Algorithmic complexity===The academic field and the engineering practice of computer programming are both largely concerned with discovering and implementing the most efficient algorithms for a given class of problems.", "For this purpose, algorithms are classified into ''orders'' using so-called Big O notation, which expresses resource use, such as execution time or memory consumption, in terms of the size of an input.", "Expert programmers are familiar with a variety of well-established algorithms and their respective complexities and use this knowledge to choose algorithms that are best suited to the circumstances.===Methodologies===The first step in most formal software development processes is requirements analysis, followed by testing to determine value modeling, implementation, and failure elimination (debugging).", "There exist a lot of different approaches for each of those tasks.", "One approach popular for requirements analysis is Use Case analysis.", "Many programmers use forms of Agile software development where the various stages of formal software development are more integrated together into short cycles that take a few weeks rather than years.", "There are many approaches to the Software development process.Popular modeling techniques include Object-Oriented Analysis and Design (OOAD) and Model-Driven Architecture (MDA).", "The Unified Modeling Language (UML) is a notation used for both the OOAD and MDA.A similar technique used for database design is Entity-Relationship Modeling (ER Modeling).Implementation techniques include imperative languages (object-oriented or procedural), functional languages, and logic languages.===Measuring language usage===It is very difficult to determine what are the most popular modern programming languages.", "Methods of measuring programming language popularity include: counting the number of job advertisements that mention the language, the number of books sold and courses teaching the language (this overestimates the importance of newer languages), and estimates of the number of existing lines of code written in the language (this underestimates the number of users of business languages such as COBOL).Some languages are very popular for particular kinds of applications, while some languages are regularly used to write many different kinds of applications.", "For example, COBOL is still strong in corporate data centers often on large mainframe computers, Fortran in engineering applications, scripting languages in Web development, and C in embedded software.", "Many applications use a mix of several languages in their construction and use.", "New languages are generally designed around the syntax of a prior language with new functionality added, (for example C++ adds object-orientation to C, and Java adds memory management and bytecode to C++, but as a result, loses efficiency and the ability for low-level manipulation).===Debugging===The first known actual bug causing a problem in a computer was a moth, trapped inside a Harvard mainframe, recorded in a log book entry dated September 9, 1947.", "\"Bug\" was already a common term for a software defect when this insect was found.Debugging is a very important task in the software development process since having defects in a program can have significant consequences for its users.", "Some languages are more prone to some kinds of faults because their specification does not require compilers to perform as much checking as other languages.", "Use of a static code analysis tool can help detect some possible problems.", "Normally the first step in debugging is to attempt to reproduce the problem.", "This can be a non-trivial task, for example as with parallel processes or some unusual software bugs.", "Also, specific user environment and usage history can make it difficult to reproduce the problem.After the bug is reproduced, the input of the program may need to be simplified to make it easier to debug.", "For example, when a bug in a compiler can make it crash when parsing some large source file, a simplification of the test case that results in only few lines from the original source file can be sufficient to reproduce the same crash.", "Trial-and-error/divide-and-conquer is needed: the programmer will try to remove some parts of the original test case and check if the problem still exists.", "When debugging the problem in a GUI, the programmer can try to skip some user interaction from the original problem description and check if remaining actions are sufficient for bugs to appear.", "Scripting and breakpointing is also part of this process.Debugging is often done with IDEs.", "Standalone debuggers like GDB are also used, and these often provide less of a visual environment, usually using a command line.", "Some text editors such as Emacs allow GDB to be invoked through them, to provide a visual environment." ], [ "Programming languages{{anchor|Languages}}", "Different programming languages support different styles of programming (called ''programming paradigms'').", "The choice of language used is subject to many considerations, such as company policy, suitability to task, availability of third-party packages, or individual preference.", "Ideally, the programming language best suited for the task at hand will be selected.", "Trade-offs from this ideal involve finding enough programmers who know the language to build a team, the availability of compilers for that language, and the efficiency with which programs written in a given language execute.", "Languages form an approximate spectrum from \"low-level\" to \"high-level\"; \"low-level\" languages are typically more machine-oriented and faster to execute, whereas \"high-level\" languages are more abstract and easier to use but execute less quickly.", "It is usually easier to code in \"high-level\" languages than in \"low-level\" ones.Programming languages are essential for software development.", "They are the building blocks for all software, from the simplest applications to the most sophisticated ones.Allen Downey, in his book ''How To Think Like A Computer Scientist'', writes::The details look different in different languages, but a few basic instructions appear in just about every language::*Input: Gather data from the keyboard, a file, or some other device.", ":*Output: Display data on the screen or send data to a file or other device.", ":*Arithmetic: Perform basic arithmetical operations like addition and multiplication.", ":*Conditional Execution: Check for certain conditions and execute the appropriate sequence of statements.", ":*Repetition: Perform some action repeatedly, usually with some variation.Many computer languages provide a mechanism to call functions provided by shared libraries.", "Provided the functions in a library follow the appropriate run-time conventions (e.g., method of passing arguments), then these functions may be written in any other language." ], [ "Programmers", "Computer programmers are those who write computer software.", "Their jobs usually involve:*Prototyping*Coding*Debugging*Documentation*Integration*Maintenance*Requirements analysis*Software architecture*Software testing*SpecificationAlthough programming has been presented in the media as a somewhat mathematical subject, some research shows that good programmers have strong skills in natural human languages, and that learning to code is similar to learning a foreign language." ], [ "See also", "*Computer networking*Programming best practices*Systems programming" ], [ "References", "=== Sources ===* ***" ], [ "Further reading", "* A.K.", "Hartmann, '' Practical Guide to Computer Simulations'', Singapore: World Scientific (2009)* A.", "Hunt, D. Thomas, and W. Cunningham, ''The Pragmatic Programmer.", "From Journeyman to Master'', Amsterdam: Addison-Wesley Longman (1999)* Brian W. Kernighan, ''The Practice of Programming'', Pearson (1999)* Weinberg, Gerald M., ''The Psychology of Computer Programming'', New York: Van Nostrand Reinhold (1971)* Edsger W. Dijkstra, ''A Discipline of Programming'', Prentice-Hall (1976)* O.-J.", "Dahl, E.W.Dijkstra, C.A.R.", "Hoare, ''Structured Programming'', Academic Press (1972)* David Gries, ''The Science of Programming'', Springer-Verlag (1981)" ], [ "External links", "***" ] ]

[ [ "On the Consolation of Philosophy" ], [ "Introduction", "'''''On the Consolation of Philosophy''''' (), often titled as '''''The Consolation of Philosophy''''' or simply the '''''Consolation''''', is a philosophical work by the Roman philosopher Boethius.", "Written in 523 while he was imprisoned and awaiting execution by the Ostrogothic King Theodoric, it is often described as the last great Western work of the Classical Period.", "Boethius' ''Consolation'' heavily influenced the philosophy of late antiquity, as well as Medieval and early Renaissance Christianity." ], [ "Description", "''On the Consolation of Philosophy'' was written in AD 523 during a one-year imprisonment Boethius served while awaiting trial—and eventual execution—for the alleged crime of treason under the Ostrogothic King Theodoric the Great.", "Boethius was at the very heights of power in Rome, holding the prestigious office of ''magister officiorum'', and was brought down by treachery.", "This experience inspired the text, which reflects on how evil can exist in a world governed by God (the problem of theodicy), and how happiness is still attainable amidst fickle fortune, while also considering the nature of happiness and God.", "In 1891, the academic Hugh Fraser Stewart described the work as \"by far the most interesting example of prison literature the world has ever seen.", "\"Boethius writes the book as a conversation between himself and a female personification of philosophy, referred to as \"Lady Philosophy\".", "Philosophy consoles Boethius by discussing the transitory nature of wealth, fame, and power (\"no man can ever truly be secure until he has been forsaken by Fortune\"), and the ultimate superiority of things of the mind, which she calls the \"one true good\".", "She contends that happiness comes from within, and that virtue is all that one truly has because it is not imperiled by the vicissitudes of fortune.Boethius engages with the nature of predestination and free will, the problem of evil and the \"problem of desert\", human nature, virtue, and justice.", "He speaks about the nature of free will and determinism when he asks whether God knows and sees all, or does man have free will.", "On human nature, Boethius says that humans are essentially good, and only when they give in to \"wickedness\" do they \"sink to the level of being an animal.\"", "On justice, he says criminals are not to be abused, but rather treated with sympathy and respect, using the analogy of doctor and patient to illustrate the ideal relationship between prosecutor and criminal.===Outline===''On the Consolation of Philosophy'' is laid out as follows:*'''Book I:''' Boethius laments his imprisonment before he is visited by Philosophy, personified as a woman.", "*'''Book II:''' Philosophy illustrates the capricious nature of Fate by discussing the \"wheel of Fortune\"; she further argues that true happiness lies in the pursuit of wisdom.", "*'''Book III:''' Building on the ideas laid out in the previous book, Philosophy explains how wisdom has a divine source; she also demonstrates how many earthly goods (e.g., wealth, beauty) are fleeting at best.", "*'''Book IV:''' Philosophy and Boethius discuss the nature of good and evil, with Philosophy offering several explanations concerned with evil events and why the wicked can never attain true happiness.", "*'''Book V:''' Boethius asks Philosophy about the role Chance plays in the order of everything.", "Philosophy argues that Chance is guided by Providence.", "Boethius then asks Philosophy about the compatibility of an omniscient God and free will." ], [ "Interpretation", "In the ''Consolation'', Boethius answered religious questions without reference to Christianity, relying solely on natural philosophy and the Classical Greek tradition.", "He believed in the correspondence between faith and reason.", "The truths found in Christianity would be no different from the truths found in philosophy.", "In the words of Henry Chadwick, \"If the ''Consolation'' contains nothing distinctively Christian, it is also relevant that it contains nothing specifically pagan either...it is a work written by a Platonist who is also a Christian.", "\"Boethius repeats the Macrobius model of the Earth in the center of a spherical cosmos.The philosophical message of the book fits well with the religious piety of the Middle Ages.", "Boethius encouraged readers not to pursue worldly goods such as money and power, but to seek internalized virtues.", "Evil had a purpose, to provide a lesson to help change for good; while suffering from evil was seen as virtuous.", "Because God ruled the universe through Love, prayer to God and the application of Love would lead to true happiness.", "The Middle Ages, with their vivid sense of an overruling fate, found in Boethius an interpretation of life closely akin to the spirit of Christianity.", "The ''Consolation'' stands, by its note of fatalism and its affinities with the Christian doctrine of humility, midway between the pagan philosophy of Seneca the Younger and the later Christian philosophy of consolation represented by Thomas à Kempis.The book is heavily influenced by Plato and his dialogues (as was Boethius himself).", "Its popularity can in part be explained by its Neoplatonic and Christian ethical messages, although current scholarly research is still far from clear exactly why and how the work became so vastly popular in the Middle Ages." ], [ "Influence", "Lady Fortune with the Wheel of Fortune in a medieval manuscript of a work by BoccaccioFrom the Carolingian epoch to the end of the Middle Ages and beyond, ''The Consolation of Philosophy'' was one of the most popular and influential philosophical works, read by statesmen, poets, historians, philosophers, and theologians.", "It is through Boethius that much of the thought of the Classical period was made available to the Western Medieval world.", "It has often been said Boethius was the \"last of the Romans and the first of the Scholastics\".Translations into the vernacular were done by famous notables, including King Alfred (Old English), Jean de Meun (Old French), Geoffrey Chaucer (Middle English), Queen Elizabeth I (Early Modern English) and Notker Labeo (Old High German).", "Boethius's ''Consolation of Philosophy'' was translated into Italian by Alberto della Piagentina (1332), Anselmo Tanso (Milan, 1520), Lodovico Domenichi (Florence, 1550), Benedetto Varchi (Florence, 1551), Cosimo Bartoli (Florence, 1551) and Tommaso Tamburini (Palermo, 1657).Found within the ''Consolation'' are themes that have echoed throughout the Western canon: the female figure of wisdom that informs Dante, the ascent through the layered universe that is shared with Milton, the reconciliation of opposing forces that find their way into Chaucer in ''The Knight's Tale'', and the Wheel of Fortune so popular throughout the Middle Ages.Citations from it occur frequently in Dante's ''Divina Commedia''.", "Of Boethius, Dante remarked: \"The blessed soul who exposes the deceptive world to anyone who gives ear to him.", "\"Boethian influence can be found nearly everywhere in Geoffrey Chaucer's poetry, e.g.", "in ''Troilus and Criseyde'', ''The Knight's Tale'', ''The Clerk's Tale'', ''The Franklin's Tale'', ''The Parson's Tale'' and ''The Tale of Melibee'', in the character of Lady Nature in ''The Parliament of Fowls'' and some of the shorter poems, such as ''Truth'', ''The Former Age'' and ''Lak of Stedfastnesse''.", "Chaucer translated the work in his ''Boece''.The Italian composer Luigi Dallapiccola used some of the text in his choral work ''Canti di prigionia'' (1938).", "The Australian composer Peter Sculthorpe quoted parts of it in his opera or music theatre work ''Rites of Passage'' (1972–73), which was commissioned for the opening of the Sydney Opera House but was not ready in time.Tom Shippey in ''The Road to Middle-earth'' says how \"Boethian\" much of the treatment of evil is in Tolkien's ''The Lord of the Rings''.", "Shippey says that Tolkien knew well the translation of Boethius that was made by King Alfred and he quotes some \"Boethian\" remarks from Frodo, Treebeard, and Elrond.Miniatures of Boethius teaching and in prison from a 1385 Italian manuscriptBoethius and ''Consolatio Philosophiae'' are cited frequently by the main character Ignatius J. Reilly in the Pulitzer Prize-winning ''A Confederacy of Dunces'' (1980).It is a prosimetrical text, meaning that it is written in alternating sections of prose and metered verse.", "In the course of the text, Boethius displays a virtuosic command of the forms of Latin poetry.", "It is classified as a Menippean satire, a fusion of allegorical tale, platonic dialogue, and lyrical poetry.Edward Gibbon described the work as \"a golden volume not unworthy of the leisure of Plato or Tully.", "\"In the 20th century, there were close to four hundred manuscripts still surviving, a testament to its popularity.Of the work, C. S. Lewis wrote: \"To acquire a taste for it is almost to become naturalised in the Middle Ages.", "\"===Reconstruction of lost songs===Hundreds of Latin songs were recorded in neumes from the ninth century through to the thirteenth century, including settings of the poetic passages from Boethius's ''The Consolation of Philosophy''.", "The music of this song repertory had long been considered irretrievably lost because the notational signs indicated only melodic outlines, relying on now-lapsed oral traditions to fill in the missing details.", "However, research conducted by Sam Barrett at the University of Cambridge, extended in collaboration with medieval music ensemble Sequentia, has shown that principles of musical setting for this period can be identified, providing crucial information to enable modern realisations.", "Sequentia performed the world premiere of the reconstructed songs from Boethius's ''The Consolation of Philosophy'' at Pembroke College, Cambridge, in April 2016, bringing to life music not heard in over 1,000 years; a number of the songs were subsequently recorded on the CD ''Boethius: Songs of Consolation.", "Metra from 11th-Century Canterbury'' (Glossa, 2018).", "The detective story behind the recovery of these lost songs is told in a documentary film, and a website launched by the University of Cambridge in 2018 provides further details of the reconstruction process, bringing together manuscripts, reconstructions, and video resources." ], [ "See also", "*Allegory in the Middle Ages*Consolatio*Girdle book*''Metres of Boethius''*Prosimetrum*Stoicism*The Wheel of Fortune" ], [ "References", "=== Sources ===* * Boethius, ''The Consolation of Philosophy''.", "** Trans.", "Joel C. Relihan, (Hackett Publishing), 2001.", "** Trans.", "P. G. Walsh, (Oxford World's Classics), 2001.", "** Trans.", "Richard H. Green, (Library of the Liberal Arts), 1962.", "** Trans.", "Victor Watts, (Penguin Classics), 2000.", "* Cochrane, Charles Norris., ''Christianity and Classical Culture'', 1940, .", "* Henry Chadwick, ''Boethius: The Consolations of Music, Logic, Theology and Philosophy'', 1990, * .", "* .", "* Relihan, Joel C., ''Ancient Menippean Satire'', 1993, * Relihan, Joel C., ''The Prisoner's Philosophy: Life and Death in Boethius's Consolation, '' 2007, .", "* Sanderson Beck, ''The Consolation of Boethius'' an analysis and commentary.", "1996.", "* ''The Cambridge History of English and American Literature'', Volume I Ch.6.5: ''De Consolatione Philosophiae'', 1907–1921." ], [ "External links", "* * ''Consolatio Philosophiae'' from Project Gutenberg, HTML conversion, originally translated by H. R. James, London 1897.", "* ''Consolatio Philosophiae'' in the original Latin with English comments at the University of Georgetown* ''First Performance in 1000 years: lost songs from the Middle Ages are brought back to life''* Medieval translations into Old English by Alfred the Great, Old High German by Notker Labeo, Middle (originally Old) French by Jean de Meun, and Middle English by Geoffrey Chaucer** ''The Consolation of Philosophy'', many translations and commentaries from Internet Archive* ''The Consolation of Philosophy'', Translated by: W.V.", "Cooper : J.M.", "Dent and Company London 1902 The Temple Classics, edited by Israel Golancz M.A.", "Online reading and multiple ebook formats at Ex-classics." ] ]

[ [ "Crouching Tiger, Hidden Dragon" ], [ "Introduction", "'''''Crouching Tiger, Hidden Dragon''''' is a 2000 wuxia martial arts adventure film directed by Ang Lee and written for the screen by Wang Hui-ling, James Schamus, and Tsai Kuo-jung.", "The film stars Chow Yun-fat, Michelle Yeoh, Zhang Ziyi, and Chang Chen.", "It is based on the Chinese novel of the same name, serialized between 1941 and 1942 by Wang Dulu, the fourth part of his ''Crane Iron'' pentalogy.A multinational venture, the film was made on a US$17 million budget, and was produced by Edko Films and Zoom Hunt Productions in collaboration with China Film Co-productions Corporation and Asian Union Film & Entertainment for Columbia Pictures Film Production Asia in association with Good Machine International.", "The film premiered at the Cannes Film Festival on 18 May 2000, and was theatrically released in the United States on 8 December.", "With dialogue in Standard Chinese, subtitled for various markets, ''Crouching Tiger, Hidden Dragon'' became a surprise international success, grossing $213.5 million worldwide.", "It grossed US$128 million in the United States, becoming the highest-grossing foreign produced Mandarin-language film in American history.", "The film was the first foreign-language film to break the $100 million mark in the United States.The film received universal acclaim from critics, praised for its story, direction, cinematography, and martial arts sequences.", "''Crouching Tiger, Hidden Dragon'' won over 40 awards and was nominated for 10 Academy Awards in 2001, including Best Picture, and won Best Foreign Language Film, Best Art Direction, Best Original Score, and Best Cinematography, receiving the most nominations ever for a non-English-language film at the time, until 2018's ''Roma'' tied this record.", "The film also won four BAFTAs and two Golden Globe Awards, each of them for Best Foreign Film.", "For retrospective years, ''Crouching Tiger'' is often cited as one of the finest wuxia films ever made and has been widely regarded as one of the greatest films of the 21st century." ], [ "Plot", "In Qing dynasty China, Li Mu Bai is a renowned Wudang swordsman, and his friend Yu Shu Lien, a female warrior, heads a private security company.", "Shu Lien and Mu Bai have long had feelings for each other, but because Shu Lien had been engaged to Mu Bai's close friend, Meng Sizhao before his death, Shu Lien and Mu Bai feel bound by loyalty to Meng Sizhao and have not revealed their feelings to each other.", "Mu Bai, choosing to retire from the life of a swordsman, asks Shu Lien to give his fabled 400-year-old sword \"Green Destiny\" to their benefactor Sir Te in Beijing.", "Long ago, Mu Bai's teacher was killed by Jade Fox, a woman who sought to learn Wudang secrets.", "While at Sir Te's place, Shu Lien meets Yu Jiaolong, or Jen, who is the daughter of the rich and powerful Governor Yu and is about to get married.One evening, a masked thief sneaks into Sir Te's estate and steals the Green Destiny.", "Sir Te's servant Master Bo and Shu Lien trace the theft to Governor Yu's compound, where Jade Fox had been posing as Jen's governess for many years.", "Soon after, Mu Bai arrives in Beijing and discusses the theft with Shu Lien.", "Master Bo makes the acquaintance of Inspector Tsai, a police investigator from the provinces, and his daughter May, who have come to Beijing in pursuit of Fox.", "Fox challenges the pair and Master Bo to a showdown that night.", "Following a protracted battle, the group is on the verge of defeat when Mu Bai arrives and outmaneuvers Fox.", "She reveals that she killed Mu Bai's teacher because he would sleep with her, but refuse to take a woman as a disciple, and she felt it poetic justice for him to die at a woman's hand.", "Just as Mu Bai is about to kill her, the masked thief reappears and helps Fox.", "Fox kills Tsai before fleeing with the thief (who is revealed to be Jen).", "After seeing Jen fight Mu Bai, Fox realizes Jen had been secretly studying the Wudang manual.", "Fox is illiterate and could only follow the diagrams, whereas Jen's ability to read the manual allowed her to surpass her teacher in martial arts.At night, a bandit named Lo breaks into Jen's bedroom and asks her to leave with him.", "In the past, when Governor Yu and his family were traveling in the western deserts of Xinjiang, Lo and his bandits raided Jen's caravan and Lo stole her comb.", "She pursued him to his desert cave to retrieve her comb.", "However, the pair soon fell in love.", "Lo eventually convinced Jen to return to her family, though not before telling her a legend of a man who jumped off a mountain to make his wishes come true.", "Because the man's heart was pure, his wish was granted and he was unharmed, but flew away never to be seen again.", "Lo has come now to Beijing to persuade Jen not to go through with her arranged marriage.", "However, Jen refuses to leave with him.", "Later, Lo interrupts Jen's wedding procession, begging her to leave with him.", "Shu Lien and Mu Bai convince Lo to wait for Jen at Mount Wudang, where he will be safe from Jen's family, who are furious with him.", "Jen runs away from her husband on their wedding night before the marriage can be consummated.", "Disguised in men's clothing, she is accosted at an inn by a large group of warriors; armed with the Green Destiny and her own superior combat skills, she emerges victorious.Jen visits Shu Lien, who tells her that Lo is waiting for her at Mount Wudang.", "After an angry exchange, the two women engage in a duel.", "Shu Lien is the superior fighter, but Jen wields the Green Destiny and is able to destroy each weapon that Shu Lien wields, until Shu Lien finally manages to defeat Jen with a broken sword.", "When Shu Lien shows mercy, Jen wounds Shu Lien in the arm.", "Mu Bai arrives and pursues Jen into a bamboo forest, where he offers to take her as his student.", "Jen agrees if he can take Green Destiny from her in three moves.", "Mu Bai is able to take the sword in only one move, but Jen reneges on her promise, and Mu Bai throws the sword over a waterfall.", "Jen dives after the sword and is rescued by Fox.", "Fox puts Jen into a drugged sleep and places her in a cavern, where Mu Bai and Shu Lien discover her.", "Fox suddenly attacks them with poisoned needles.", "Mu Bai mortally wounds Fox, only to realize that one of the needles has hit him in the neck.", "Before dying, Fox confesses that her goal had been to kill Jen because Jen had hidden the secrets of Wudang's fighting techniques from her.Contrite, Jen leaves to prepare an antidote for the poisoned dart.", "With his last breath, Mu Bai finally confesses his love for Shu Lien.", "He dies in her arms as Jen returns.", "Shu Lien forgives Jen, telling her to go to Lo and always be true to herself.", "The Green Destiny is returned to Sir Te.", "Jen goes to Mount Wudang and spends the night with Lo.", "The next morning, Lo finds Jen standing on a bridge overlooking the edge of the mountain.", "In an echo of the legend that they spoke about in the desert, she asks him to make a wish.", "Lo wishes for them to be together again, back in the desert.", "Jen leaps from the bridge, falling into the mists below." ], [ "Cast", "Actor Chow Yun-Fat who portrayed Li Mu BaiCredits from British Film Institute:* Chow Yun-fat as Li Mu Bai (, )* Michelle Yeoh as Yu Shu Lien (, )* Zhang Ziyi as Jen Yu (, )* Chang Chen as Lo \"Dark Cloud\" Xiao Hou (, )* Lang Sihung as Sir Te (, )* Cheng Pei-pei as Jade Fox (, )* as Governor Yu (, )* Wang Deming as Inspector Tsai (, )* Li Li as Tsai May (, )* Hai Yan as Madam Yu (, )* Gao Xi'an as Bo (, )* as Aunt Wu (, )* Zhang Jinting as De Lu (, )* Du Zhenxi as Uncle Jiao (, )* Li Kai as Gou Jun Pei (, )* Feng Jianhua as Shining Phoenix Mountain Gou (, )* Ma Zhongxuan as Iron Arm Mi (, )* Li Bao-Cheng as Flying Machete Chang (, )* Yang Yongde as Monk Jing (, )" ], [ "Themes and interpretations", "===Title===The title \"''Crouching Tiger, Hidden Dragon''\" is a literal translation of the Chinese idiom \"臥虎藏龍\" which describes a place or situation that is full of unnoticed masters.", "It is from a poem of the ancient Chinese poet Yu Xin (513–581) that reads \"暗石疑藏虎，盤根似臥龍\", which means \"behind the rock in the dark probably hides a tiger, and the coiling giant root resembles a crouching dragon\".", "The title also has several other layers of meaning.", "On one level, the Chinese characters in the title connect to the narrative that the last character in Xiaohu and Jiaolong's names mean \"tiger\" and \"dragon\", respectively.", "On another level, the Chinese idiomatic phrase is an expression referring to the undercurrents of emotion, passion, and secret desire that lie beneath the surface of polite society and civil behavior, which alludes to the film's storyline.=== Gender roles ===The success of the Disney animated feature ''Mulan'' (1998) popularized the image of the Chinese woman warrior in the west.", "The storyline of ''Crouching Tiger, Hidden Dragon'' is mostly driven by the three female characters.", "In particular, Jen is driven by her desire to be free from the gender role imposed on her, while Shu Lien, herself oppressed by the gender role, tries to lead Jen back into the role deemed appropriate for her.", "Some prominent martial arts disciplines are traditionally held to have been originated by women, e.g., Wing Chun.", "The film's title refers to masters one does not notice, which necessarily includes mostly women, and therefore suggests the advantage of a female bodyguard.===Poison===Poison is also a significant theme in the film.", "The Chinese word \"毒\" (''dú'') means not only physical poison but also cruelty and sinfulness.", "In the world of martial arts, the use of poison is considered an act of one who is too cowardly and dishonorable to fight; and indeed, the only character who explicitly fits these characteristics is Jade Fox.", "The poison is a weapon of her bitterness and quest for vengeance: she poisons the master of Wudang, attempts to poison Jen, and succeeds in killing Mu Bai using a poisoned needle.", "In further play on this theme by the director, Jade Fox, as she dies, refers to the poison from a young child, \"the deceit of an eight-year-old girl\", referring to what she considers her own spiritual poisoning by her young apprentice Jen.", "Li Mu Bai himself warns that, without guidance, Jen could become a \"poison dragon\".===China of the imagination===The story is set during the Qing dynasty (1644–1912), but it does not specify an exact time.", "Lee sought to present a \"China of the imagination\" rather than an accurate vision of Chinese history.", "At the same time, Lee also wanted to make a film that Western audiences would want to see.", "Thus, the film is shot for a balance between Eastern and Western aesthetics.", "There are some scenes showing uncommon artistry for the typical martial arts film such as an airborne battle among wispy bamboo plants." ], [ "Production", "The film was adapted from the novel ''Crouching Tiger, Hidden Dragon'' by Wang Dulu, serialized between 1941 and 1942 in ''Qingdao Xinmin News''.", "The novel is the fourth in a sequence of five.", "In the contract reached between Columbia Pictures and Ang Lee and Hsu Li-kong, they agreed to invest US$6 million in filming, but the stipulated recovery amount must be more than six times before the two parties will start to pay dividends.===Casting===Shu Qi was Ang Lee's first choice for the role of Jen, but she turned it down.===Filming===Mount Cangyan, including the bridge pictured above, was one of many filming locations.Although its Academy Award for Best Foreign Language Film was presented to Taiwan, ''Crouching Tiger, Hidden Dragon'' was in fact an international co-production between companies in four regions: the Chinese company China Film Co-production Corporation, the American companies Columbia Pictures Film Production Asia, Sony Pictures Classics, and Good Machine, the Hong Kong company Edko Films, and the Taiwanese Zoom Hunt Productions, as well as the unspecified United China Vision and Asia Union Film & Entertainment, created solely for this film.The film was made in Beijing, with location shooting in Urumchi, Western Provinces, Taklamakan Plateau, Shanghai and Anji of China.", "The first phase of shooting was in the Gobi Desert where it consistently rained.", "Director Ang Lee noted, \"I didn't take one break in eight months, not even for half a day.", "I was miserable—I just didn't have the extra energy to be happy.", "Near the end, I could hardly breathe.", "I thought I was about to have a stroke.\"", "The stunt work was mostly performed by the actors themselves and Ang Lee stated in an interview that computers were used \"only to remove the safety wires that held the actors\" aloft.", "\"Most of the time you can see their faces,\" he added.", "\"That's really them in the trees.", "\"Another compounding issue was the difference between accents of the four lead actors: Chow Yun-fat is from Hong Kong and speaks Cantonese natively; Michelle Yeoh is from Malaysia and grew up speaking English and Malay, so she learned the Standard Chinese lines phonetically; Chang Chen is from Taiwan and he speaks Standard Chinese in a Taiwanese accent.", "Only Zhang Ziyi spoke with a native Mandarin accent that Ang Lee wanted.", "Chow Yun Fat said, on \"the first day of shooting, I had to do 28 takes just because of the language.", "That's never happened before in my life.", "\"The film specifically targeted Western audiences rather than the domestic audiences who were already used to Wuxia films.", "As a result, high-quality English subtitles were needed.", "Ang Lee, who was educated in the West, personally edited the subtitles to ensure they were satisfactory for Western audiences.===Soundtrack===The score was composed by Dun TAN in 1999.It was played for the movie by the Shanghai Symphony Orchestra, the Shanghai National Orchestra and the Shanghai Percussion Ensemble.", "It features solo passages for cello played by Yo-Yo Ma.", "The \"last track\" (\"A Love Before Time\") features Coco Lee, who later sang it at the Academy Awards.", "The composer Chen Yuanlin also collaborated in the project.", "The music for the entire film was produced in two weeks.", "Tan the next year (2000) adapted his filmscore as a cello concerto called simply \"Crouching Tiger.\"" ], [ "Release", "===Marketing===The film was adapted into a video game and a series of comics, and it led to the original novel being adapted into a 34-episode Taiwanese television series.", "The latter was released in 2004 as ''New Crouching Tiger, Hidden Dragon'' for Northern American release.===Home media===The film was released on VHS and DVD on 5 June 2001 by Columbia TriStar Home Entertainment.", "It was also released on UMD on 26 June 2005.In the United Kingdom, it was watched by viewers on television in 2004, making it the year's most-watched foreign-language film on television.=== Restoration ===The film was re-released in a 4K restoration by Sony Pictures Classics in 2023." ], [ "Reception", "===Box office===The film premiered in cinemas on 8 December 2000, in limited release within the United States.", "During its opening weekend, the film opened in 15th place, grossing $663,205 in business, showing at 16 locations.", "On 12 January 2001, ''Crouching Tiger, Hidden Dragon'' premiered in cinemas in wide release throughout the U.S., grossing $8,647,295 in business, ranking in sixth place.", "The film ''Save the Last Dance'' came in first place during that weekend, grossing $23,444,930.The film's revenue dropped by almost 30% in its second week of release, earning $6,080,357.For that particular weekend, the film fell to eighth place, screening in 837 theaters.", "''Save the Last Dance'' remained unchanged in first place, grossing $15,366,047 in box-office revenue.", "During its final week in release, ''Crouching Tiger, Hidden Dragon'' opened in a distant 50th place with $37,233 in revenue.", "The film went on to top out domestically at $128,078,872 in total ticket sales through a 31-week theatrical run.", "Internationally, the film took in an additional $85,446,864 in box-office business for a combined worldwide total of $213,525,736.For 2000 as a whole, the film cumulatively ranked at a worldwide box-office performance position of 19.===Critical response===''Crouching Tiger, Hidden Dragon'' was widely acclaimed in the Western world, receiving numerous awards.", "On Rotten Tomatoes, the film holds an approval rating of 98% based on 168 reviews, with an average rating of 8.6/10.The site's critical consensus states: \"The movie that catapulted Ang Lee into the ranks of upper echelon Hollywood filmmakers, ''Crouching Tiger, Hidden Dragon'' features a deft mix of amazing martial arts battles, beautiful scenery, and tasteful drama.\"", "Metacritic reported the film had an average score of 94 out of 100, based on 32 reviews, indicating \"universal acclaim\".Some Chinese-speaking viewers were bothered by the accents of the leading actors.", "Neither Chow (a native Cantonese speaker) nor Yeoh (who was born and raised in Malaysia) spoke Mandarin Chinese as a mother tongue.", "All four main actors spoke Standard Chinese with vastly different accents: Chow speaks with a Cantonese accent, Yeoh with a Malaysian accent, Chang Chen with a Taiwanese accent, and Zhang Ziyi with a Beijing accent.", "Yeoh responded to this complaint in a 28 December 2000, interview with ''Cinescape''.", "She argued, \"My character lived outside of Beijing, and so I didn't have to do the Beijing accent.\"", "When the interviewer, Craig Reid, remarked, \"My mother-in-law has this strange Sichuan-Mandarin accent that's hard for me to understand,\" Yeoh responded: \"Yes, provinces all have their very own strong accents.", "When we first started the movie, Cheng Pei Pei was going to have her accent, and Chang Zhen was going to have his accent, and this person would have that accent.", "And in the end nobody could understand what they were saying.", "Forget about us, even the crew from Beijing thought this was all weird.", "\"The film led to a boost in popularity of Chinese wuxia films in the western world, where they were previously little known, and led to films such as ''Hero'' and ''House of Flying Daggers'', both directed by Zhang Yimou, being marketed towards Western audiences.", "The film also provided the breakthrough role for Zhang Ziyi's career, who noted:''Film Journal'' noted that ''Crouching Tiger, Hidden Dragon'' \"pulled off the rare trifecta of critical acclaim, boffo box-office and gestalt shift\", in reference to its ground-breaking success for a subtitled film in the American market.===Accolades===Gathering widespread critical acclaim at the Toronto and New York film festivals, the film also became a favorite when Academy Awards nominations were announced in 2001.The film was screened out of competition at the 2000 Cannes Film Festival.", "The film received ten Academy Award nominations, which was the highest ever for a non-English language film, up until it was tied by ''Roma'' (2018).The film is ranked at number 497 on ''Empire'''s 2008 list of the 500 greatest movies of all time.", "and at number 66 in the magazine's 100 Best Films of World Cinema, published in 2010.In 2010, the Independent Film & Television Alliance selected the film as one of the 30 Most Significant Independent Films of the last 30 years.In 2016, it was voted the 35th-best film of the 21st century as picked by 177 film critics from around the world in a poll conducted by BBC.The film was included in BBC's 2018 list of The 100 greatest foreign language films ranked by 209 critics from 43 countries around the world.", "In 2019, ''The Guardian'' ranked the film 51st in its 100 best films of the 21st century list.", "Award Category Nominee Result Ammy Awards Best Hollywood Picture Ang Lee Best Male Actor in a Cinematic Production Chow Yun Fat Best Female Actor in a Cinematic Production Michelle Yeoh Zhang Ziyi 73rd Academy AwardsBest PictureBill Kong, Hsu Li-kong, and Ang LeeBest DirectorAng LeeBest Adapted ScreenplayWang Hui-ling, James Schamus, and Tsai Kuo-jungBest Foreign Language FilmTaiwanBest Art DirectionArt Direction and Set Decoration: Tim YipBest CinematographyPeter PauBest Costume DesignTim YipBest Film EditingTim SquyresBest Original ScoreTan DunBest Original SongJorge Calandrelli, Tan Dun and James Schamus for \"A Love Before Time\"2000 American Society of Cinematographers AwardsBest CinematographyPeter Pau54th British Academy Film AwardsBest Film Best Film Not in the English LanguageBest Actress in a Leading RoleMichelle YeohBest Actress in a Supporting RoleZhang ZiyiBest CinematographyPeter PauBest Makeup and HairBest EditingTim SquyresBest Costume DesignTim YipBest DirectorAng LeeBest MusicTan DunBest Adapted ScreenplayWang Hui-ling, James Schamus, and Tsai Kuo-jung Best Production DesignTim YipBest SoundBest Visual EffectsBroadcast Film Critics Association Awards 2000Best Foreign FilmChicago Film Critics Association Awards 2000Most Promising ActressZhang Ziyi Best Original ScoreTan DunBest CinematographyPeter PauBest Foreign Film2000 Directors Guild of America AwardsBest DirectorAng Lee2000 Film Fest Gent festivalGeorges Delerue AwardTan Dun58th Golden Globe AwardsBest Foreign Language FilmBest DirectorAng LeeBest Original ScoreTan Dun20th Hong Kong Film AwardsBest FilmBest DirectorAng LeeBest ScreenplayWang Hui-ling, James Schamus, and Tsai Kuo-jungBest ActorChow Yun-fatBest ActressZhang ZiyiMichelle YeohBest Supporting ActorChang ChenBest Supporting ActressCheng Pei-peiBest CinematographyPeter PauBest Film EditingTim SquyresBest Art DirectionTim YipBest Costume Make Up DesignTim YipBest Action ChoreographyYuen Wo-pingBest Original Film ScoreTan DunBest Original Film SongTan Dun, Jorge Calandrelli, Yee Kar-yeung, Coco LeeBest Sound DesignEugene GeartyHugo Award (2001)Best Dramatic PresentationIndependent Spirit Awards 2000Best PictureBest DirectorAng LeeBest Supporting ActressZhang ZiyiLos Angeles Film Critics Association Awards 2000Best PictureBest CinematographyPeter PauBest Music ScoreTan DunBest Production DesignTim YipNational Board of Review Awards 2000Best Foreign Language Film Top Foreign Films2000 New York Film Critics Circle AwardsBest CinematographyPeter Pau Toronto Film Critics Association Awards 2000Best PictureBest DirectorAng LeeBest ActressMichelle YeohBest Supporting ActressZhang Ziyi2000 Toronto International Film FestivalPeople's Choice AwardAng LeeWriters Guild of America Awards 2000Best Adapted ScreenplayWang Hui-ling, James Schamus, and Tsai Kuo-jung 37th Golden Horse Awards – 2000 Best Feature Film Best Director Ang Lee Best Leading Actress Michelle Yeoh Zhang Ziyi Best Screenplay Adaption Wang Hui-ling, James Schamus, and Tsai Kuo-jung Best Cinematography Peter Pau Best Film Editing Tim Squyres Best Art Direction Tim Yip Best Original Score Tan Dun Best Sound Design Eugene Gearty Best Action Choreography Yuen Wo-ping Best Visual Effects Leo Lo, and Rob Hodgson 54th Bodil AwardsBest Non-American Film Online Film Critics Society Awards 2000 Best Picture Best Foreign Language Film Best Director Ang Lee Best Supporting Actress Zhang Ziyi Best Cinematography Peter Pau Best Editing Tim Squyres Best Original Score Tan Dun" ], [ "Sequel", "In 2001, it was reported that director Ang Lee was planning to make a sequel to the film.", "''Crouching Tiger, Hidden Dragon: Sword of Destiny'', was released in 2016.It was directed by Yuen Wo-ping, who was the action choreographer for the first film.", "It is a co-production between Pegasus Media, China Film Group Corporation, and the Weinstein Company.", "Unlike the original film, the sequel was filmed in English for international release and dubbed into Chinese for Chinese releases.", "''Sword of Destiny'' is based on ''Iron Knight, Silver Vase'', the next (and last) novel in the Crane–Iron Pentalogy.", "It features a mostly new cast, headed by Donnie Yen.", "Michelle Yeoh reprised her role from the original.", "Zhang Ziyi was also approached to appear in ''Sword of Destiny'' but refused, stating that she would only appear in a sequel if Ang Lee were directing it.In the West, the sequel was for the most part not shown in theaters, instead being distributed direct-to-video by the streaming service Netflix." ], [ "Posterity", "The theme of Janet Jackson's song \"China Love\" was related to the film by MTV News, in which Jackson sings of the daughter of an emperor in love with a warrior, unable to sustain relations when forced to marry into royalty.The names of the pterosaur genus ''Kryptodrakon'' and the ceratopsian genus ''Yinlong'' (both meaning \"hidden dragon\" in Greek and Chinese respectively) allude to the film.The character of Lo, or \"Dark Cloud\" the desert bandit, influenced the development of the protagonist of the ''Prince of Persia'' series of video games.In the video game Def Jam Fight for NY: The Takeover there are two hybrid fighting styles that pay homage to this movie.", "Which have the following combinations: Crouching tiger (Martial Arts + Streetfighting + Submissions) and Hidden Dragon (Martial Arts + Streetfighting + Kickboxing)." ], [ "See also", "* Anji County* Clear waters and green mountains" ], [ "References" ], [ "Further reading", "* * – Collection of articles*" ], [ "External links", "* * * * * * * *" ] ]

[ [ "Charlemagne" ], [ "Introduction", "'''Charlemagne''' ( ; 2 April 748 – 28 January 814) was King of the Franks from 768, King of the Lombards from 774, and Emperor of the Carolingian Empire from 800, all until his death in 814.Charlemagne succeeded in uniting the majority of Western Central Europe, and he was the first recognized emperor to rule in the west after the fall of the Western Roman Empire approximately three centuries earlier.", "Charlemagne's rule saw a program of political and societal changes that had a lasting impact on Europe in the Middle Ages.A member of the Frankish Carolingian dynasty, Charlemagne was the eldest son of Pepin the Short and Bertrada of Laon.", "With his brother Carloman I, he became king of the Franks in 768 following Pepins's death, and became sole ruler in 771.As king, he continued his father's policy towards the protection of the papacy and became its chief defender, removing the Lombards from power in northern Italy in 774.Charlemagne's reign saw a period of expansion that led to the conquests of Bavaria, Saxony, and northern Spain, as well as other campaigns that led Charlemagne to extend his rule over a vast area of Europe.", "He spread Christianity to his new conquests, often by force, as seen at the Massacre of Verden against the Saxons.In 800, Charlemagne was crowned as emperor in Rome by Pope Leo III.", "While historians debate about the exact significance of the coronation, the title represented the height of prestige and authority he had achieved.", "Charlemagne's position as the first emperor in the West in over 300 years brought him into conflict with the contemporary Eastern Roman Empire based in Constantinople.", "By his assumption of the imperial title, he is considered the forerunner of the line of Holy Roman Emperors that lasted into the nineteenth century.", "As king and emperor, Charlemagne engaged in a number of reforms in administration, law, education, military organization, and religion which shaped Europe for centuries.", "The stability of his reign saw the beginning of a period of significant cultural activity known as the Carolingian Renaissance.Charlemagne died in 814, and was laid to rest in the Aachen Cathedral, in his imperial capital city of Aachen.", "He was succeeded by his only surviving son Louis the Pious.", "After Louis, the Frankish kingdom would be divided, eventually coalescing into West and East Francia, which would respectively become France and the Holy Roman Empire.", "Charlemagne's profound impact on the Middle Ages, and the influence on the vast territory he ruled has led him to be called the \"Father of Europe\".", "He is seen as a founding figure by multiple European states, and many historical royal houses of Europe trace their lineage back to him.", "Charlemagne has been the subject of artwork, monuments, and literature since the medieval period, and has received veneration in the Catholic Church." ], [ "Name", "Various languages were spoken in Charlemagne's world, and he was known to contemporaries as in the Old High German he spoke; to Romance speakers; and (or alternatively ) in Latin, the formal language of writing and diplomacy.", "Charles is the modern English form of these names.", "The name Charlemagne, by which the emperor is normally known in English, comes from the French , meaning \"Charles the Great\".", "In modern German, he is known as .", "The Latin epithet ('great') may have been associated with him already in his lifetime, but this is not certain.", "The contemporary ''Royal Frankish Annals'' routinely call him ('Charles the great king').", "As an epithet, it is certainly attested in the works of the Poeta Saxo around 900, and it became commonly applied to him by 1000.Charlemagne was named after his grandfather Charles Martel.", "The name and its derivatives are unattested before their use by Charles Martel and Charlemagne.", "Karolus was adapted into Slavic languages as their word for king (present in modern languages, e.g.", ", , and ), either through the influence of Charlemagne or his great-grandson Charles the Fat." ], [ "Early life and rise to power", "===Political background and ancestry===By the sixth century, the western Germanic tribe of the Franks had been Christianised, due in considerable measure to the conversion of their king Clovis I to Catholicism.", "The Franks had established a kingdom in Gaul in the wake of the Fall of the Western Roman Empire.", "This kingdom, Francia, grew to encompass nearly all of modern France and Switzerland, along with parts of modern Germany and the Low Countries under the rule of the Merovingian dynasty.", "Francia was often divided into several sub-kingdoms under different Merovingian kings, due to the partible inheritance practiced by the Franks.", "The late 7th century saw a period of war and instability following the murder of King Childeric II, which led to factional struggles among the Frankish aristocrats.In 687, Pepin of Herstal, mayor of the palace of the Frankish sub-kingdom Austrasia, ended the strife between various kings and their mayors with his victory at the Battle of Tertry.", "Pepin was the grandson of two important figures of Austrasia: Arnulf of Metz and Pepin of Landen.", "The mayors of the palace had gained influence as the Merovingian kings' own power waned due to the divisions of the kingdom and several succession crises.", "Pepin was eventually succeeded by his son Charles, later known as Charles Martel.", "Charles did not support a Merovingian successor upon the death of King Theuderic IV in 737, leaving the throne vacant.", "Charles made plans to divide the kingdom between his sons Carloman and Pepin the Short, who succeeded upon his death in 741.The brothers placed the Merovingian Childeric III on the throne in 743.In 747, Carloman abdicated and entered a monastery at Rome.", "Carloman had at least two sons, and the elder, Drogo took his place.===Birth===Charlemagne was the first-born son of Pepin the Short and his wife Bertada, a member of an influential noble Austrasian family.", "His birth date is uncertain, though was most likely in 748.An older tradition, based on the 9th-century biographer Einhard's report of Charlemagne being 72 at death, gives a birth year of 742.Einhard admittedly did not know much of Charlemagne's early life, and, not knowing the emperor's true age, still presented an exact date in keeping with the Roman imperial biographies of Suetonius which he used as a model.", "The German scholar Karl Werner challenged the acceptance of Einhard's date and cited a near-contemporary additions to annals which recorded Charlemagne's birth in 747.Lorsch Abbey commemorated Charlemagne's date of birth as 2 April since the mid-9th century, and this date is likely genuine.", "As the annalists recorded the start of the year from Easter rather than 1 January, Matthais Becher built off of Werner's work and showed that 2 April in the year recorded would have actually been in 748.2 April 748 has therefore become the accepted date among scholars.", "The date of 742 had led to the belief that Charlemagne may have been an illegitimate child, as Pepin and Bertrada did not marry until 744.Charlemagne's place of birth is also unknown; the Frankish palaces in Vaires-sur-Marne and Quierzy are among the places suggested by scholars.===Language and education===Sketch thought to be of Charlemagne Einhard speaks of Charlemagne's ('native toungue').", "Most scholars have identified this as a form of Old High German, probably a Rhenish Franconian dialect.", "Due to the prevalence in Francia of the \"rustic Roman\" language that was rapidly developing into Old French, he was probably functionally bilingual in both Germanic and Romance dialects from a young age.", "Charlemagne also spoke Latin, and according to Einhard could understand and perhaps speak some Greek.Charlemagne's father Pepin had been educated at the abbey of Saint-Denis, though the extent of Charlemagne's formal education is unknown.", "He almost certainly was trained in military matters as a youth in Pepin's court, which was itinerant.", "Charlemagne also asserted his own education in the liberal arts when encouraging their study by his children and others, though it is unknown whether his study was as a child or at court during his later life.", "The question of Charlemagne's literacy is subject to debate, and there is little direct evidence from contemporary sources.", "He normally had texts read aloud to him and dictated responses and decrees, though this was not unusual even for a literate ruler at the time.", "The German historian Johannes Fried considers it likely that Charlemagne would have been able to read, though the medievalist Paul Dutton writes that \"the evidence for his ability to read is circumstantial and inferential at best,\" and concludes it likely that he never properly mastered the skill.", "Einhard makes no direct mention of Charlemagne reading, but recorded that he only attempted to learn to write later in life.===Accession and joint reign with Carloman===There are only sparse references to Charlemagne in the Frankish annals during his father's lifetime.", "By 751 or 752, Pepin deposed Childeric and replaced him as king.", "Early Carolingian-influenced sources claim that Pepin's seizure of the throne was sanctioned beforehand by Pope Stephen II, but modern historians dispute this.", "It is possible papal approval only came when Stephen traveled to Francia in 754, apparently to request Pepin's aid against the Lombards, and on this trip anointed Pepin as king, legitimizing his rule.", "Charlemagne had been sent to greet and escort the Pope, and he and his younger brother Carloman were anointed along with their father.", "Around the same time, Pepin sidelined Drogo, sending him and his brother to a monastery.20th-century painting of Charlemagne's coronation at Noyon in 768.Charlemagne began issuing charters in his own name in 760.Next year, he joined his father's campaign against Aquitaine.", "Aquitaine, led by Duke Hunald was constantly in rebellion during Pepin's reign.", "Pepin fell ill on campaign there and died on 24 September 768, and Charlemagne and Carloman succeeded their father.", "They had separate coronations, Charlemagne at Noyon and Carloman at Soissons, each on 9 October.", "The brothers maintained separate palaces and separate spheres of influence, though they were considered joint rulers of a single Frankish kingdom.", "The ''Royal Frankish Annals'' report that Charlemagne ruled Austrasia and Carloman ruled Burgundy, Provence, Aquitaine, and Alamannia, with no mention made of which brother received Neustria.", "The immediate concern of the brothers was the ongoing uprising in Aquitane.", "While they marched into Aquitaine together, Carloman returned to Francia for unknown reasons, and Charlemagne completed the campaign on his own.", "Charlemagne's capture of Duke Hunald marked the end of ten years of war in the attempt to bring Aquitaine in line.Carloman's refusal to complete in the war against Aquitaine led to a rift between the two kings.", "It is uncertain why Carloman abandoned the campaign.", "It is possible that the brothers disagreed over control over the territory, or that Carloman was focusing on securing his rule in the north of Francia.", "Regardless of strife between the kings, they still maintained a joint rule out of practicality.", "Both Charlemagne and Carloman worked to obtain the support of the clergy and local elites to solidify their positions.Pope Stephen III was elected in 768, but was briefly deposed by an antipope before being restored to Rome.", "With factional struggle still occurring, Stephen sought the support of the Frankish kings.", "Both brothers sent troops to Rome, each hoping to exert their own influence.", "The Lombard king Desiderius also had interests in the affairs in Rome, and Charlemagne moved to gain him as an ally.", "Desiderius already had alliances with Bavaria and Benevento through the marriages of his daughters to their dukes, and an alliance with Charlemagne would add to his influence.", "Charlemagne's mother Betrada went on his behalf to Lombardy in 770, where she brokered the marriage alliance before returning to Francia with Charlemagne's new bride.", "Desiderius's daughter is traditionally named Desiderata, though she may have been named Gerperga.", "Being anxious at the prospect of a Frankish–Lombard alliance, Pope Stephen sent a letter to both Frankish kings decrying the marriage, while also separately seeking closer ties with Carloman.Charlemagne had already had a relationship with the Frankish noblewoman Himiltrude, having a son in 769 they named Pepin.", "Paul the Deacon wrote in his 784 that Pepin was born \"before legal marriage\", but does not specify as to whether Charles and Himiltrude were never married, were joined in a non-canonical marriage or , or if they married after Pepin was born.", "Pope Stephen's letter described the relationship as a legitimate marriage, but he had a vested interest in preventing Charlemagne from marrying Desiderius's daughter.Carloman died suddenly on 4 December 771, leaving Charlemagne as sole king of the Franks.", "He moved immediately to secure his hold on his brother's territory, forcing Carloman's widow Gerberga to flee to Desiderius's court in Lombardy with their children.", "In response, Charlemagne ended his marriage to Desiderius's daughter and married Hildegard, daughter of count Gerold, a powerful magnate of Carloman's kingdom.", "This was both a reaction to Desiderius's sheltering of Carloman's family as well as a move to secure the Gerold's support." ], [ "King of the Franks and the Lombards", "===Annexation of the Lombard kingdom===Political map of Europe in 771, showing the Franks and their neighbors.Charlemagne's first campaigning season as sole king of the Franks was spent on the eastern frontier, in his first war against the Saxons.", "Saxons had engaged in border raiding against the Frankish kingdom, and Charlemagne responded, destroying the pagan irminsul shrine at Eresburg and seizing the Saxons' gold and silver.", "The successful war helped secure Charlemagne's reputation among his brother's former supporters as well as providing funds for further military action.", "This campaign was the beginning of over thirty years of near continuous warfare against the Saxons by Charlemagne.Pope Adrian I succeeded Stephen III in 772, and sought the return of papal control of cities captured by Desiderius.", "Unable to get results directly by dealing with the Lombard king, Adrian sent emissaries to Charlemagne to gain his support in recovering papal territory.", "Charlemagne, motivated by this appeal and the dynastic threat posed by the presence of Carloman's sons in the Lombard court, gathered his forces and moved to intervene.", "First seeking diplomatic solutions, he offered gold to Desiderius in exchange for the return of the papal territories and his nephews.", "These overtures were rejected, and Charlemagne's army (with command divided between himself and his uncle Bernard) crossed the Alps to besiege the Lombard capital Pavia in late 773.Charlemagne's second son, also named Charles, had been born in 772, and Charlemagne brought the child and his wife to the camp at Pavia.", "Hildegard was pregnant, and gave birth to a daughter named Adelhaid.", "The baby was sent back to Francia, but died on the way.", "Charlemagne left Bernard to maintain the siege at Pavia while he took a force to capture Verona, where Desiderius's son Adalgis had taken Carloman's sons.", "Charlemagne captured the city, and no further record exists of his nephews or of Carloman's wife, and their fates are unknown.", "The historian Janet Nelson likens them to the \"princes in the tower\" of the Wars of the Roses.", "Fried puts forth the possibilities that the boys were forced into a monastery (a common solution for dynastic issues) or that \"an act of murder smoothed Charlemagne’s ascent to power.\"", "Adalgis was not captured by Charlemagne and fled to Constantinople.Pope Adrian receiving Charlemagne at RomeCharlemagne left the siege in April 774 to celebrate Easter at Rome.", "Pope Adrian arranged for a formal welcome of the Frankish king, and the two swore oaths to each other over the relics of St. Peter.", "Adrian presented a copy of the agreement between Pepin and Stephen III outlining the papal lands and rights Pepin had agreed to protect and restore.", "What exact lands and rights the agreement pertained to is unclear, and would remain a point of dispute for centuries.", "Charlemagne deposited a copy of the agreement in the chapel above St. Peter's tomb as a symbol of his commitment, then left Rome to continue the siege at Pavia.Shortly after his return to Pavia, disease struck the besieged Lombards and they surrendered the city by June.", "Charlemagne deposed Desiderius and took the title king of the Lombards for himself.", "The complete takeover of one kingdom by another was \"extraordinary\" (Roger Collins), and the authors of ''The Carolingian World'' say it was \"without parallel\".", "Charlemagne was able to secure the support of the Lombard nobles and Italian urban elites to seize power in a mostly peaceful annexation.", "The historian Rosamond McKitterick suggests that the elective nature of the Lombard monarchy eased Charlemagne's takeover; Collins attributes the easy conquest to the Lombard elite's \"presupposition that rightful authority was in the hands of the one powerful enough to seize it\".", "Charlemagne shortly returned to Francia with the Lombard royal treasury and with Desiderius and his family, who would be confined to a monastery for the rest of their days.===Frontier wars in Saxony and Spain===Charlemagne's additions to the Frankish KingdomSaxons had taken advantage of Charlemagne's absence in Italy to raid the Frankish borderlands, leading to a counter-raid in the autumn of 774 and a campaign of reprisal in 775.Charlemagne was soon drawn back to Italy, as Duke Hrodgaud of Friuli rebelled against him.", "Charlemagne quickly crushed the rebellion and distributed Hrogaud's lands to Franks to better consolidate his rule in Lombardy.", "He wintered in Italy, and further consolidated his power through issuing charters and legislation as well as taking Lombard hostages.", "In the midst of the 775 Saxon and Friulian campaigns, his daughter Rotrude was born in Francia.Returning north, Charlemagne waged another brief but destructive campaign against the Saxons in 776.This led to the submission of many Saxons, who turned over captives and lands as well as submitting to baptism as Christians.", "In 777, Charlemagne held an assembly at Paderborn with both Frankish and Saxon men, and many more Saxons came under his rule, but the Saxon magnate Widukind fled to Denmark to make preparations for a new rebellion.", "Charlemagne's third son Carloman was also born this year.", "Also present at the Paderborn assembly were representatives of dissident factions from al-Andalus (or Muslim Spain).", "These included the son and son-in-law Yusuf ibn Abd al-Rahman al-Fihri, the former governor of Cordóba, who had been ousted by the Caliph Abd al-Rahman in 756.They sought Charlemagne's support for al-Fihri's restoration.", "Also present was Sulayman al-Arabi, governor of Barcelona and Girona, who wished to become part of the Frankish kingdom and receive Charlemagne's protection rather than remain under the rule of Cordoba.", "Charlemagne, seeing an opportunity to strengthen the security of the kingdom's southern frontier and further extend his influence, agreed to intervene.", "Crossing the Pyrenees, his army found little resistance until an ambush by Basque forces in 778 at the Battle of Roncevaux Pass.", "The Franks had been defeated in the battle and withdrew from the campaign, though with most of the army intact.===Building the dynasty===Adrian crowning Louis as Charlemagne looks on.Charlemagne returned to Francia to greet his new twin sons Louis and Lothair, who had been born while he was in Spain.", "Lothair would die in infancy.", "Again, Saxons had seized on the king's absence to raid.", "Charlemagne sent an army to Saxony in 779, while he took time to hold assemblies, legislate, and address a famine in Francia.", "Hildegard gave birth to another daughter, Bertha.", "Charlemagne himself returned to Saxony in 780, holding assemblies where he received hostages from Saxon nobles and oversaw their baptisms.In the spring of 781, Charlemagne and Hildegard traveled with their four younger children to Rome (leaving Pepin and Charles at Worms), making a journey requested by Adrian since 775.Adrian baptized Carloman and renamed him Pepin, resulting in him sharing a name with his half brother.", "Louis and the newly renamed Pepin were then anointed and crowned, Pepin appointed king of the Lombards and Louis king of Aquitaine.", "This was not merely nominal, as the young kings were sent to reside in their kingdoms under the care of regents and advisors.", "A delegation from the Byzantine regent Empress Irene came to meet Charlemagne during his stay in Rome, and he agreed to betroth his daughter Rotrude to her son Emperor Constantine VI.Hildegard also gave birth to her eighth child, Gisela during this trip to Italy.", "After the royal family's return to Francia, she had her final pregnancy, and died from resulting complications on 30 April 783.The child, named for her, died shortly thereafter.", "Charlemagne commissioned epitaphs for both his wife and daughter, and arranged for daily mass to be said at Hildegard's tomb.", "Charlemagne's mother Betrada died shortly after Hildegard, on 12 July 783.By the end of the year, Charlemagne remarried to Fastrada, daughter of the East Frankish count Radolf.===Saxon resistance and reprisal===Charlemagne receiving the submission of Widukind at Paderborn in 785, painted by Ary Scheffer.In summer 782, Widukind returned from Denmark to attack the Frankish positions in Saxony.", "He defeated a Frankish army, possibly due to rivalry among the Frankish counts leading it.", "After learning of the defeat, Charlemagne came to Verden but Widukind fled before his arrival.", "Charlemagne convoked the Saxon magnates to an assembly, and compelled them to turn over prisoners to him as he regarded their previous acts as a treachery.", "The annals record that Charlemagne had 4,500 Saxon prisoners beheaded in what is called the Massacre of Verden.", "Fried writes that \"although this figure may be exaggerated, the basic truth of the event is not in doubt.\"", "Historian Alessandro Barbero regards it as \"perhaps the greatest stain on his reputation.\"", "Likely in the immediate aftermath, or as a prescursor for the massacre, Charlemagne issued the ''Capitulatio de partibus Saxoniae'' legal code.", "Featuring a harsh set of laws that included death penalty for pagan practices, the ''Capitulatio'' \"constituted a program for the forced conversion of the Saxons\" (Barbero) and \"aimed...at suppressing Saxon identity\" (Nelson).Charlemagne's focus for the next several years would be to attempt to complete the subjugation of the Saxons.", "Concentrating first in Westphalia in 783, he pushed into Thuringia in 784 as Charles the Younger continued operations in the west.", "At each stage of the campaigns, the Frankish armies seized wealth and carried Saxon captives into slavery.", "Unusually, Charlemagne remained campaigning through the winter rather than resting his army.", "By 785, Charlemagne had cowed the Saxon resistance and commanded complete control of Westphalia.", "That summer, he met Widukind and convinced him to end his resistance.", "Widukind agreed to be baptized with Charlemagne as his godfather, ending this phase of the Saxon Wars.===Benevento, Bavaria, and Pepin's revolt===Charlemagne traveled to Italy in 786, arriving by Christmas.", "Aiming to extend his influence further into southern Italy, he marched into the Duchy of Benevento.", "Duke Arechis fled to a fortified position at Salerno, before offering Charlemagne his fealty.", "Charlemagne accepted the submission along with hostages, who included Arechis's son Grimoald.", "While in Italy, Charlemagne also met with envoys from Constantinople.", "Empress Irene had called the 787 Second Council of Nicaea, but did not inform Charlemagne nor invite any Frankish bishops.", "Charlemagne, likely in reaction to the perceived slight of this exclusion, broke the betrothal between his daughter Rotrude and Constantine VI.Solidus'' of Benevento with Grimoald's effigy and Charlemagne's name (DOMS CAR RX, the Lord King Charles).After Charlemagne left Italy, Arechis sent envoys to Irene to offer an alliance.", "He suggested she send a Byzantine army along with Adalgis, the exiled son of Desiderus, to remove the Franks form power in Lombardy.", "Before his plans could be finalized, both Aldechis and his elder son Romuald died of illness within weeks of each other.", "Charlemagne sent Grimoald back to Benevento to serve as duke and return it to Frankish suzerainty.", "The Byzantine army did invade but were repulsed by the Frankish and Lombard forces.As affairs were being settled in Italy, Charlemagne turned his attention to Bavaria.", "Bavaria was ruled by Duke Tassilo, Charlemagne's first cousin who had been installed by Pepin the Short in 748.Tassilo's sons were also grandsons of Desiderius, and therefore a potential threat to Charlemagne's rule in Lombardy.", "The two neighboring rulers had a growing rivalry throughout their reigns, but had sworn oaths of peace to each other in 781.In 784, Rotpert, Charlemagne's viceroy in Italy, accused Tassilo of conspiring with Widukind in Saxony and unsuccessfully attacked the Bavarian city of Bolzano.", "Charlemagne gathered his forces to prepare an invasion of Bavaria in 787.Dividing the army, the Franks launched a three-pronged attack.", "Quickly realizing the poor position he was in, Tassilo agreed to surrender and recognize Charlemagne as his overlord.", "The next year, Tassilo was accused of plotting with the Avars to attack Charlemagne.", "Tassilo was deposed and sent to a monastery, and Charlemagne absorbed Bavaria into his kingdom.", "Charlemagne spent the next several years based in Regensburg, largely focused on consolidating his rule Bavaria and warring against the Avars.", "Successful campaigns against the Avars were launched from Bavaria and Italy in 788, and Charlemagne led campaigns in 791 and 792.In 789, Charlemagne gave his son Charles the Younger rule over Maine in Neustria, leaving Pepin the Hunchback as his only son without lands.", "Charlemagne's relationship with Himiltrude was by this point apparently seen as definitively illegitimate at Charlemagne's court, and Pepin by result was being sidelined in the succession.", "In 792, as his father and brothers were all gathered at Regensburg, Pepin conspired with Bavarian nobles to assassinate them and install himself as king.", "The plot was discovered and revealed to Charlemagne before it could go ahead.", "Pepin was sent to a monastery and many of his co-conspirators were executed.The early 790s saw a marked focus on ecclesiastical affairs by Charlemagne.", "He summoned a council at Regensburg in 792 to address the theological controversey over the Adoptionism doctrine in the Spanish church, as well as formulate a response to the Second Council of Nicea.", "The council condemned Adoptionism as a heresy and led to the production of the ''Libri Carolini'', a detailed argument against Nicea's canons.", "In 794, Charlemagne called another council at Frankfurt.", "The council confirmed Regensburg's positions on Adoptionism and Nicea, recognised the deposition of Tassilo, set grain prices, reformed the Frankish coinage system, forbade abbesses to give blessings to men, and endorsed prayer in vernacular languages.", "Soon after the council, Fastrada fell ill and died.", "Charlemagne married Alamannian noblewoman Luitgard shortly after.===Continued wars with the Saxons and Avars===With Saxon resistance continuing, Charlemagne gathered an army after the council of Frankfurt.", "This was the beginning of a series of annual campaigns that would last through 799.The campaigns of the 790s were even more destructive than those of earlier decades, with the annal writers frequently referring to Charlemagne \"burning\", \"ravaging\", \"devastating\", and \"laying waste\" to the Saxon lands.", "Charlemagne forcibly removed a large number of Saxons to Francia, installing Frankish elites and soldiers in their place.", "Charlemagne's extended wars in Saxony led to him establishing his court at Aachen, which had easy access to the frontier.", "At Aachen, he built a large palace, including a chapel which is now part of the Aachen Cathedral.", "It was during this period the Einhard joined the court.", "In the south, Pepin of Italy engaged in further wars against the Avars which led to the collapse of their kingdom and the expansion of Frankish rule east.During the wars of the 790s, Charlemagne also worked through diplomatic means to expand his influence, with particular attention on the Anglo-Saxon kingdoms of Britain.", "Charles the Younger proposed a marriage pact with the daughter of King Offa of Mercia, but Offa insisted that Charlemagne's daughter Bertha also be given as a bride for his own son.", "Charlemagne refused this arrangement, and the marriage did not occur.", "Charlemagne and Offa did enter into a formal peace in 796, protecting trade and securing the rights of English pilgrims to pass through Francia on their way to Rome.", "Charlemagne also served as host and protector of several deposed English rulers who were later restored: Eadbehrt of Kent, Ecgberht, King of Wessex, and Eardwulf of Northumbria.", "Nelson writes that Charlemagne treated the Anglo-Saxon kingdoms \"like satellite states,\" even establishing direct relations with English bishops.", "Charlemagne also made an alliance with Alfonso II of Asturias, though Einhard describes Alfonso as a \"dependent\" of Charlemagne." ], [ "Reign as emperor", "===Coronation===Imperial Coronation of Charlemagne, by Friedrich Kaulbach, 1861Leo III had become pope in 795, and faced political opposition since his accession.", "In April 799, his enemies accused him of various crimes and attacked him, attempting to remove his eyes and tongue.", "Leo escaped and fled north to seek Charlemagne's help.", "Charlemagne continued his campaign against the Saxons before breaking off to meet Leo at Paderborn in September.", "Charlemagne, hearing evidence from both the Pope and his enemies, sent Leo back to Rome along with royal legates, who had instructions to reinstate the Pope and investigate the matter further.", "It was not until August of the next year that Charlemagne himself made plans to go to Rome, after an extensive tour of his lands in Neustria.", "Charlemagne met Leo in November near Mentana, at the twelfth milestone outside Rome, the traditional location where Roman emperors began their formal entry to the city.", "Charlemagne presided over an assembly to hear the charges, but believed that no one could sit in judgement of the Pope.", "Instead, Leo swore an oath on 23 December declaring his innocence of all charges, which was accepted.", "On 25 December 800, at mass in St. Peter's Basilica on Christmas Day, Leo acclaimed Charlemagne as emperor and crowned him.", "In doing so, Charlemagne became the first reigning emperor in the west since the deposition of Romulus Augustulus in 476.His son, Charles the Younger, was anointed as king by Leo at the same time.Coronation of Charlemagne, drawing by Julius Schnorr von Karolsfeld, 1840.Historians differ as to intentions behind the imperial coronation, the extent to which Charlemagne was aware of it or participated in its planning, and the significance of the events to those present and to Charlemagne's reign.", "Contemporary Frankish and papal sources differ in their emphasis and representation of events.", "Einhard insists that Charlemagne would not have entered the church had he known of the Pope's plan; modern historians have regarded his report as truthful, or rejected it as a \"literary device\" used as a sign of Charlemagne's humility.", "Collins argues that the actions surrounding the coronation indicate that it was planned by Charlemagne as early as his meeting with Leo in 799, and Fried writes that Charlemagne planned to adopt the title of emperor by 798 \"at the latest.\"", "In the years before the coronation, Charlemagne's courtier Alcuin had referred to Charlemagne's realm as an ''Imperium Christianum'' (\"Christian Empire\"), wherein, \"just as the inhabitants of the Roman Empire had been united by a common Roman citizenship\", presumably this new empire would be united by a common Christian faith.", "This is the view of French scholar Henri Pirenne when he says \"Charles was the Emperor of the ''ecclesia'' as the Pope conceived it, of the Roman Church, regarded as the universal Church\".Pope Leo III, crowning Charlemagne from ''Chroniques de France ou de Saint Denis'', vol.", "1; France, second quarter of 14th century.For both Leo and Charlemagne, the Roman Empire remained a significant contemporary power in European politics, especially in Italy.", "The Byzantines continued to hold a substantial portion of Italy, with borders not far south of Rome.", "Empress Irene had seized the throne from her son Constantine VI in 797, deposing and blinding him.", "Irene was the first reigning Byzantine empress, and faced opposition in Constantinople both for her gender and for her method of accession.", "One of the earliest narrative sources for the coronation, the Annals of Lorsch present the presence of a female ruler in Constantinople as a vacancy in the imperial title, and therefore a justification for Leo to crown Charlemagne.", "Pirenne disputes this, saying that the coronation \"was not in any sense explained by the fact that at this moment a woman was reigning in Constantinople.\"", "Leo's main motivations may have been the desire to increase his own standing after his political difficulties, showing himself as a power broker and securing Charlemagne as his powerful ally and protector.", "The Byzantine Empire's lack of ability to influence events in Italy and support the papacy were also important in Leo's position.", "The ''Royal Frankish Annals'' emphasize that Leo prostrated himself before Charlemagne after crowning him, an act of submission standard in Roman coronation rituals from the time of Diocletian.", "This account represents Leo, rather being the superior of Charlemagne, merely acting as an agent of the Roman people in recognizing their acclamation of Charlemagne as emperor.The historian Henry Mayr-Harting argues that assumption of the imperial title by Charlemagne was an effort to incorporate the Saxons into the Frankish realm, as they did not have a native tradition of kingship.", "However, Costambeys ''et al.''", "note in ''The Carolingian World'' that \"since Saxony had not been in the Roman empire it is hard to see on what basis an emperor would have been any more welcomed.\"", "These authors argue that the decision to take the title of emperor was aimed at furthering Charlemagne's influence in Italy, as an appeal to traditional authority recognized by Italian elites both within and especially outside his current control.", "''The Coronation of Charlemagne'', by assistants of Raphael, Collins concurs that becoming emperor gave Charlemagne \"the right to try to impose his rule over the whole of Italy\", and regards this as a motivator for the coronation.", "He also notes the \"element of political and military risk\" inherent in the affair, due to the opposition of the Byzantine Empire as well as potential opposition from the Frankish elite as the imperial title could draw him further into Mediterranean politics.", "Collins sees several actions of Charlemagne as attempts to ensure his new title was cast in a distinctly Frankish context.Charlemagne's coronation led to a centuries-long ideological conflict between his successors and Constantinople, termed the problem of two emperors, as it could be seen as a rejection or usurpation of the Byzantine emperors' claim to be the universal, preeminent Christian rulers.", "The historian James Muldoon writes that Charlemagne may have had a more limited view of his role, seeing the title simply representing dominion over the lands he already ruled.", "Nonetheless, the title of emperor gave Charlemagne enhanced prestige and ideological authority.", "He immediately incorporated his new title into documents issued, adopting the formula \"Charles, most serene Augustus, crowned by God, great peaceful emperor governing the Roman empire, and who is by the mercy of God king of the Franks and the Lombards\" as opposed to the earlier form \"Charles, by the grace of God king of the Franks and Lombards and patrician of the Romans.\"", "The avoidance of the specific claim of being a \"Roman emperor\" as an opposed to the more neutral \"emperor governing the Roman empire\" may have been to improve relations with the Byzantines.", "This phrasing, alongside the continuation of his earlier royal titles, may also represent a view of his role as emperor as merely being the ruler of the people of the city of Rome, just as he was of the Franks and the Lombards.===Governing the empire===throne in Aachen Cathedral.Charlemagne left Italy in the summer of 801 after judging several ecclesiastical disputes in Rome and further stops in Ravenna, Pavia, and Bologna.", "He would not return to Rome again.", "Although continuing trends and style of rulership established in the 790s, the period of Charlemagne's reign from 801 onward marks a \"distinct phase\" characterized by a more stationary rule from Aachen.", "While there continued to be conflict until the end of Charlemagne's reign, the relative peace of the imperial period saw increased focus on internal governance through the issuing of laws and capitularies.", "The Franks continued to wage war, though they increasingly focused on defending and securing the empire's frontiers, and Charlemagne rarely led armies personally.", "A significant expansion of the Spanish march was achieved following a series of campaigns by Louis against the Emirate of Cordoba, culminating in the capture of Barcelona in 801, finding success where Charlemagne's own war in Northern Spain had ended in defeat.Charlemagne did not campaign in either 802 or 803.The ''Capitulare missorum generale'' issued in 802, called the \"programmatic capitulary\", was an expansive piece of legislation, with provisions governing the conduct of royal officials and requiring a loyalty oath to the emperor to be taken by all free men under his rule.", "The capitulary reformed the institution of the , officials who would now be assigned in pairs (a cleric and a lay aristocrat) to administer justice and oversee governance in defined territories.", "The emperor also ordered revisions of the Lombard and Frankish law codes.In addition to the , Charlemagne also ruled the empire through his sons as sub-kings.", "Pepin and Louis had been appointed kings of the Italy and Aquitaine respectively in 781, though both were children at the time and were ruled by regents in their minority.", "Though both had some devolved authority as kings in adulthood, Charlemagne still had ultimate authority and intervened in matters directly.", "Charles, their elder brother, had been given rule over lands in Neustria in 789 or 790, and had been made a king in 800.The 806 charter (\"division of the realm\"), set the terms of succession of the empire in the event of Charlemagne's death.", "Charles, as his eldest son in good favour, was given the largest share of the inheritance, with rule of Francia proper along with Saxony, Nordgau, and parts of Alemannia.", "The two younger sons were confirmed in their kingdoms and gained additional territories, with most of Bavaria and Alemmannia given to Pepin and Provence, Septimania, and parts of Burgundy to Louis.", "Charlemagne did not address the inheritance of the imperial title.", "The also addressed the death of any of the brothers, and urged peace between them and between any of their nephews who might inherit.===Conflict and diplomacy with the east===15th-century woodcut of Charlemagne and Irene.Following his coronation, Charlemagne sought recognition of his imperial title from Constantinople.", "Several delegations were exchanged between Charlemagne and Irene in 802 and 803.A Byzantine chronicler claims that Charlemagne made an offer of marriage to Irene, which she was close to accepting.", "Irene, however, was deposed and replaced by Nikephoros I, who was unwilling to recognize Charlemagne as emperor.", "The two empires would come into conflict over control of the Adriatic Sea (especially Istria and Veneto) several times during Nikephoros' reign, before peace negotiations commenced in 810.Charlemagne's envoys would make peace with emperor Michael I, who had succeeded his father-in-law Nikephoros.", "As part of the peace, Michael recognized Charlemagne as emperor and basileus.", "It was only following this recognition that Charlemagne would issue coins including the imperial title, though coins minted by the pope in Rome had used the titles as early as 800.Charlemagne began diplomatic contact with the Abbasid caliph Harun al-Rashid in the 790s, due to their mutual interest in affairs in Spain.", "As an early sign of friendship, Charlemagne requested an elephant as a gift from Harun.", "Harun obliged and the elephant, named Abul-Abbas arrived in Aachen in 802.Cordial relations were retained with the Abbasids during the first decade of imperial rule.", "Harun, himself at war with the Byzantines during this period, sought to ensure Charlemagne's relations with Nikephoros remained poor.", "As part of his outreach, Harun gave Charlemagne nominal rule of the Church of the Holy Sepulchre in Jerusalem, as well as other gifts.", "Harun died in 809, leading to competing claimants over succession to the caliphate.", "Under Harun's successors, conditions for Christians and Jews under the caliphate worsened, and churches and synagogues were destroyed.", "Unable to intervene directly, Charlemagne sent aid in the form of specially minted coins (also serving as propaganda for the emperor in the form of inscriptions and portraiture) and arms to Christians under the caliphate in order to restore and defend churches and monasteries.", "The souring of relations with Baghdad after Harun's death may have been the impetus for the renewed negotiations with Constantinople that would lead to Charlemagne's peace with Michael in 811.As emperor, Charlemagne became involved in a religious dispute between eastern and western Christians over the recitation of the Niceno-Constantinopolitan Creed, the fundamental statement of orthodox Christian belief.", "The original text of the creed adopted at the Council of Constantinople professed that the Holy Spirit proceeded from the Father.", "However, a tradition developed in Western Europe that the Holy Spirit proceeded from the Father \"and the Son\", inserting the Latin term .", "This difference in tradition did not cause significant conflict until 807, when Frankish monks in Bethlehem were denounced as heretics by a Greek monk for their insertion of .", "The monks appealed the dispute to Rome, where Pope Leo affirmed the text of the creed omitting the phrase and also passed the report on to Charlemagne.", "Charlemagne summoned a council at Aachen in 809, which defended the used of , and sent this decision to Rome.", "Leo consented that the Franks could maintain their tradition, but asserted that the canonical creed did not include .", "Leo went so far as to commission two silver shields with the creed in Latin and Greek which he hung in St. Peter's Basilica.===Wars with the Danes===Europe at the death of the Charlemagne in 814Raids on Charlemagne's lands by Danes, who the Franks called nordmanni (\"northmen\") began around 800.Scandinavia had been brought into contact with the Frankish world through Charlemagne's continuous wars with the Saxons.", "Charlemagne engaged in his final campaign in Saxony in 804, taking control of Saxon territory east of the Elbe and removing the Saxon population, giving the land to his Obotrite allies.", "During this campaign, the Danish king Gudfred, uneasy at the extension of Frankish power, offered to meet with Charlemagne to arrange peace and possibly hand over Saxons that had fled to him.", "These talks were not successful for unknown reasons.", "The northern frontier was quiet until 808, when Gudfred led an incursion into the Obotrite lands, extracting tribute from over half the territory.", "Charles the Younger led an army across the Elbe in response, but only attacked some of Gudfred's Slavic allies.", "Gudfred again attempted diplomatic overtures in 809, but it seems no peace was made.", "Danish pirates raided Frisia in 810, though it is uncertain if they were connected to Gudfred.", "Charlemagne sent an army to secure Frisia while he himself led a force against Gudfred, who reportedly had challenged the emperor to face him directly in battle.", "The battle never took place, as Gudfred was murdered by two of his own men before Charlemagne's arrival.", "Gudfred's nephew and successor Hemming immediately sued for peace, and a commission led by Charlemagne's cousin Wala reached a final settlement with the Danes in 811.The Danes did not pose a threat for the remainder of Charlemagne's reign, but the effects of this war and earlier expansion in Saxony would help create the factors for the intense viking raids across Europe later in the ninth century.===Final years and death===A portion of the 814 death shroud of Charlemagne.", "It represents a quadriga and was manufactured in Constantinople.The Carolingian dynasty had multiple losses in 810, as Charlemagne's sister Gisela, his daughter Rotrude, and his son Pepin of Italy died.", "His eldest sons Pepin the Hunchback and Charles the Younger both died the next year.", "The deaths of Charles and Pepin of Italy left Charlemagne's earlier plans for succession in disarray.", "In the wake of these deaths, he declared Pepin's son Bernard ruler of Italy, and his own only surviving son Louis as heir to the rest of the empire.", "He also completed a new will detailing the disposition of his property, with bequests to the Church as well as all of his children and grandchildren.", "Einhard (possibly relying on tropes from Suetonius's ''The Twelve Caesars'') recounts that Charlemagne viewed the deaths of his family members, astronomical phenomena, and other misfortunes in his last years as signs of his own impending death.", "In his final year, Charlemagne continued to govern the empire and church with energy, ordering bishops to assemble in five ecclesiastical councils.", "These culminated in a large assembly at Aachen, where Charlemagne formally crowned Louis as his co-emperor and Bernard as king in a ceremony on 11 September 813.Charlemagne became ill in the autumn of 813 and spent his last months praying, fasting, and studying the Gospels.", "He developed pleurisy, and became completely bedridden for seven days before dying on the morning of 28 January 814.Thegan, a biographer of Louis, records the emperor's last words as \"Into your hands, Lord, I commend my spirit\", quoting from .", "Charlemagne's body was prepared and buried in the chapel at Aachen by his daughters and palace officials the same day.", "Louis arrived at Aachen thirty days after his father's death, making a formal , taking charge of the palace and the empire.", "Charlemagne's remains were exhumed by Holy Roman Emperor Frederick Barbarossa in 1165, and reinterred in a new casket by Frederick II in 1215." ], [ "Legacy", "===Political legacy===Partition of the Empire after the Treaty of Verdun 843.The stability and peace of Charlemagne's reign would not long outlast him.", "Louis' reign was marked by strife, including multiple rebellions of his own sons.", "Following Louis' death, the empire was divided between West, East, and Middle Francia.", "Middle Francia saw several more divisions over subsequent generations.", "Carolingians would rule with some interruptions in East Francia until 911 and in West Francia (which would become France) until 987.After 887, the imperial title was held sporadically by a series of non-dynastic Italian rulers before lapsing in 924.East Francian King Otto the Great conquered Italy and was crowned emperor in 962.The Holy Roman Empire founded by Otto would last until its dissolution in 1806.Charlemagne served as a model for medieval rulership \"at least until the final end of empire in the West in the early nineteenth century.\"", "Charlemagne is often given the epithet \"the father of Europe\" because of the influence of his reign, and the legacy he left across the large area of the continent he ruled.", "The political structures Charlemagne established remained in place through his Carolingian successors, and continued to have influence into the eleventh century.", "During his reign, groundwork was laid for the process of concentration of power in military aristocrats that would characterize the later Middle Ages.Despite the end of ruling Carolingian lines, Charlemagne is considered a direct ancestor of European ruling houses, including the Capetian dynasty, the Ottonian dynasty, the House of Luxembourg, the House of Ivrea and the House of Habsburg.", "The Ottonians and Capetians, direct successors of the Carolingans, drew on the legacy of Charlemagne to bolster their legitimacy and prestige.", "Ottonians and future emperors would continue to hold their German coronations at Aachen through the Middle Ages.", "The marriage of Philip II of France to Isabella of Hainault, a direct descendant of Charlemagne was seen as a sign of increased legitimacy for their son Louis VIII, and association with Charlemagne by French kings continue until the monarchy's end.", "German and French rulers such as Frederick Barbarossa and Napoleon directly cited the influence of and associated themselves with Charlemagne.The city of Aachen has, since 1949, awarded an international prize (called the ''Karlspreis der Stadt Aachen'') in honour of Charlemagne.", "It is awarded annually to those who have promoted the idea of European unity.", "Winners of the prize include Richard von Coudenhove-Kalergi, the founder of the pan-European movement, Alcide De Gasperi, and Winston Churchill.===Carolingian renaissance===Charlemagne and Alcuin, 19th century.Contacts with the wider Mediterranean world through Spain and Italy, and the influx of foreign scholars at court, along with the relative stability and length of Charlemagne's reign led to a cultural revival known as the Carolingian Renaissance.", "While the beginnings of this revival are apparent under Charles Martel and Pepin, Charlemagne took an active and direct role in shaping intellectual life that led to the revival's height.", "Charlemagne promoted learning as a matter of policy and direct patronage, with the aim of creating a more effective clergy.", "The ''Admonitio generalis'' and the ''Epistola de litteris colendis'' outlined Charlemagne's policies and his aims in promoting education and learning.The intellectual life at court was dominated by Irish, Anglo-Saxon, Visigothic, and Italian scholars including Dungal of Bobbio, Alcuin of York, Theodulf of Orléans, and Peter of Pisa, though Franks such as Einhard and Angelbert also made substantial contributions.", "Aside from the intellectual activity at the palace, Charlemagne promoted ecclesiastical schools as well publicly-funded schools for elites and clergy.", "Students learned the basic tenets of Latin literacy and grammar, arithmetic, and other subjects of the medieval liberal arts.", "From their own education, it was expected that priests in even rural parishes provide basic instruction in religious matters and possibly basic literacy skills required for worship to \"the broadest level of Carolingian society.", "\"Carolingian authors produced extensive works including legal treatises, histories, and poetry as well as religious texts.", "Scriptoria at monasteries and cathedrals focused on copying of both new and old works produced an estimated 90,000 manuscripts during the ninth century.", "The Carolingian minuscule script developed and popularized during the renaissance endured in medieval copying and influenced modern typefaces.", "John J. Contreni considers the educational and learning revival under Charlemagne and his successors as \"one of the most durable and resilient elements of the Carolingian legacy.===Memory and historiography===Charlemagne was a frequent subject of and inspiration for medieval writers after his death.", "Einhard's ''Vita Karoli Magni'' \"can be said to have revived the defunct literary genre of the secular biography.\"", "Einhard drew on classical sources such as Suetonius' ''The Twelve Caesars'', the orations of Cicero, and Tacitus' ''Agricola'' to frame the structure and style of his work.", "The Carolingian period also saw an revival in the genre of mirrors for princes.", "The author of the ''Visio Karoli Magni'' written around 865 uses facts gathered apparently from Einhard and his own observations on the decline of Charlemagne's family after the dissensions war (840–43) as the basis for a visionary tale of Charles' meeting with a prophetic spectre in a dream.", "Notker's ''Gesta Karoli Magni'', written for Charlemagne's great-grandson Charles the Fat, presents moral anecdotes (''exempla'') to highlight the emperor's qualities as a ruler.arms, Castello della Manta, 1420sCharlemagne as a figure of myth and emulation grew in later centuries; Matthias Becher writes that over 1,000 legends are recorded about Charlemagne, far outstripping later emperors and kings.", "Later medieval writers painted a portrait of Charlemagne as a crusader and Christian warrior.", "Charlemagne is the main figure of the medieval literary cycle known as Matter of France.", "Works of this cycle, which originated during the period of the Crusades, centre on depictions of the emperor as a leader of Christian knights in wars against Muslims.", "The cycle includes (epic poems) such as the ''Song of Roland'', and chronicles such as the ''Historia Caroli Magni'', or Pseudo-Turpin Chronicle.", "Charlemagne was depicted as one of the Nine Worthies, becoming a fixture in medieval literature and art as an exemplar of a Christian king.Attention on Charlemagne became more scholarly in the early modern period as Eindhard's ''Vita'' and other sources began to be widely distributed.", "Political philosophers debated over Charlemagne's legacy; Montesquieu depicted him as the first constitutional monarch and protector of freemen, while Voltaire saw Charlemagne as a despotic ruler and representative of the medieval period as a Dark Age.", "As early as the sixteenth century, debate had begun over Charlemagne's \"nationality\" between German and French writers.", "These contrasting portraits – a French Charlemagne and a German Karl der Große – became especially pronounced in the nineteenth century with Napoleon's use of Charlemagne's legacy and the rise of German nationalism.", "German historiography and popular perception focused especially on the Massacre of Verden, variously emphasized with Charlemagne as the \"butcher\" of the Germanic Saxons, or downplayed as an unfortunate part of the legacy of a great German ruler.", "Historical propaganda produced under Nazi Germany initially portrayed Charlemagne as an enemy of Germany, a French ruler who had worked to take away the freedom and native religion of the German people.", "However, this quickly shifted as Adolf Hitler endorsed a portrait of Charlemagne as a great unifier of disparate tribes into the German nation.", "This allowed Hitler to co-opt Charlemagne's legacy as an ideological model for his expansionist policies.Historiography after World War II focused on Charlemagne as \"the father of Europe\" rather than a nationalistic figure, a view first advanced in the nineteenth century by the German romantic philosopher Friedrich Schlegel.", "This view has led to Charlemagne's adoption as a political symbol of European integration.", "Modern historians increasingly place Charlemagne in the context of the wider Mediterranean world, following the work of Belgian historian Henri Pirenne.===Religious impact and veneration===Palatine Chapel constructed by Charlemagne at the Aachen palace.Charlemagne gave ample attention to religious and ecclesiastical affairs, holding 23 synods during the course of his reign.", "Each was summoned to address specific issues, but in general they dealt with Church administration and organization, education of the clergy, and proper liturgy and worship.", "Charlemagne and his successors used the Christian faith as a unifying factor within the realm, and in turn worked to impose unity within the Church.", "Charlemagne implemented an edited version of the ''Dionysio-Hadriana'' book of canon law he acquired from Pope Adrian, required the use of the Rule of St. Benedict in monasteries throughout the empire, and promoted a standardized liturgy that was adapted from the rites of the Roman Church but edited to conform with Frankish practices.", "Carolingian policies of promoting unity did not eliminate the diverse practices throughout the empire, but did creating an shared ecclesiastical identity; Rosamond McKitterick terms this \"unison, not unity.", "\"The condition of all his subjects as a \"Christian people\" was an important concern of Charlemagne's.", "His policies encouraged preaching to the laity, particularly in the vernacular languages they would understand.", "Recitation the Lord's Prayer and the Apostles' Creed were abilities Charlemagne believed to be essential, and he made efforts to ensure the clergy taught these as well as other basics of Christian morality.Medieval religious historian Thomas F. X. Noble argues that the efforts of Charlemagne and his successors at standardizing the doctrine and practices of Christianity, and in harmonizing Frankish practices was essential in the development of Christianity in Europe, and writes that the distinct Roman Catholic, or Latin Church \"as an historical phenomenon, not as a theological or ecclesiological one, is a Carolingian construction.\"", "He further argues that the medieval European concept of Christendom as an overarching community of Western Christians (as opposed to a collection of local western traditions) is a result of Carolingian policies and ideology.", "Charlemagne's doctrinal policies of opposing the Second Council of Nicea and promotion of the were key steps in the growing divide between Western and Eastern Christianity.Emperor Otto III attempted to have Charlemagne canonized as a saint in 1000.In 1165, Frederick Barbarossa convinced the Antipope Paschal III to elevate him to sainthood.", "As Paschal's acts were not considered valid, Charlemagne was not recognized as a saint by the Holy See in Rome.", "Despite this lack of recognition, Charlemagne's cult became observed in Aachen, Reims, Frankfurt, Zurich, and Regensburg, and he has been venerated in France since the reign of Charles V. Charlemagne also drew attention from figures of the Protestant Reformation.", "Martin Luther criticized Charlemagne's apparent subjugation to the papacy by accepting his coronation from Leo.", "However, John Calvin and other Protestant thinkers viewed Charlemagne as a forerunner of the Reformation, citing especially the condemnation of image and relic worship in the ''Libri Carolini'', and the conflicts he and his successors had with the temporal power of the popes." ], [ "Wives, concubines, and children", "'''Wives and their children'''*Himiltrude (768–770)**Pepin the Hunchback (/770–811)*Desiderata, daughter of Desiderius, king of the Lombards (m. 770–771)*Hildegard of the Vinzgau (m. 771–783)**Charles the Younger (–811), Duke of Maine**Adalhaid (773/4–774), born while her parents were on campaign in Italy.", "She was sent back to Francia, but died before reaching Lyons**Rotrude (or Hruodrud) (–810)**Carloman, renamed Pepin (777–810), King of Italy**Louis (778–840), King of Aquitaine since 781, crowned co-emperor in 813, senior Emperor from 814**Lothair (778–779/780), twin of Louis, he died in infancy**Bertha (779/780–826)**Gisela (b.", "782)**Hildegard (782–783)*Fastrada (m. 783–794)**Theodrada (b.", "785), Abbess of Argenteuil**Hiltrude (b.", "787, d. after 808)*Luitgard (m. 794–800)'''Concubines and their children'''*Gersuinda**Adaltrude*Madelgard** Ruodhaid (d. 852), Abbess of Faremoutiers*Regina**Drogo (801–855), Bishop of Metz**Hugh (–844), archchancellor of the Empire*Adallind**Theodoric (b.", "807)*Unknown partners**Hroudhaid (b.", "784)**Richbod (805–844), Abbot of Saint-Riquier**Bernard (fl.", "843), Abbot of Moutiers-Saint-Jean AbbeyCharlemagne instructing his son Louis the PiousCharlemagne had at least twenty children with both wives and other partners throughout his life.", "After the death of his wife Luitgard in 800, he did not remarry but continued to have children with unmarried partners.", "He was determined that all his children, including his daughters, receive an education in the liberal arts.", "His children were also taught skills in accord with their aristocratic status, which included training in riding and weaponry for his sons, and embroidery, spinning and weaving for his daughters.", "Rosamond McKitterick writes that Charlemagne exercised \"a remarkable degree of patriarchal control...over his progeny,\" noting that only a handful of his children and grandchildren were raised outside his court.Charlemagne's elder, legitimate sons reigned as kings and resided at their own courts.", "Careers in the Church were arranged for his illegitimate sons.", "His daughters were resident either at court or at Chelles Abbey where Charlemagne's sister was abbess, and those at court possibly fulfilled the duties of the queen after 800.Louis and Pepin of Italy both married and had children during their father's lifetime, and Charlemagne brought Pepin's daughters into his own household after Pepin's death.", "Rotrude had been betrothed to Emperor Constantine VI, but this betrothal was ended.", "None of Charlemagne's daughters married, though several had children with unmarried partners: Bertha had two sons, Nithard and Hartnid with Charlemagne's courtier Angilbert; Rotrude had a son named Louis possibly with Count Rorgon; and Hiltrude had a son named Richbod, possibly with a count named Richwin.", "The ''Divisio Regnorum'' issued by Charlemagne in 806 provided that his legitimate daughters would be allowed to marry or become nuns after his death.", "Theodrada entered a convent, but the decisions of his other daughters are unknown." ], [ "Appearance and iconography", "Einhard gives a first-hand description of Charlemagne's appearance later in life:In 1861, Charlemagne's tomb was opened by scientists who reconstructed his skeleton and estimated it to be measured .", "A 2010 estimate of his height from an X-ray and CT scan of his tibia was .", "This puts him in the 99th percentile of height for his period, given that average male height of his time was .", "The width of the bone suggested he was slim in build.Charlemagne wore his hair short, in an abandonment begun by his father of the Merovingian tradition of long-haired monarchs.", "He had a mustache, possibly in imitation of the Ostrogothic king Theoderic the Great, and contrasted with the bearded Merovingian kings.", "Future Carolingian monarchs would adopt this style.", "Paul Dutton notes the ubiquitous presence of a crown in portraits of Charlemagne and other Carolingian rulers replacing the earlier Merovingian royal symbol of long hair.", "A ninth-century statuette depicts either Charlemagne or his grandson Charles the Bald and shows the subject as mustachioed and with short hair, and this appearance is also shown on contemporary coinage.By the twelfth century, Charlemagne was described as bearded rather than mustachioed in literary sources such as the ''Song of Roland'' and the Pseduo-Turpin Chronicle, as well as other sources in Latin, French, and German.", "The Pseudo-Turpin uniquely claims that his hair was brown.", "Later art and iconography of Charlemagne would follow suit, generally depicting him in a later medieval style as bearded and with longer hair." ], [ "Notes" ], [ "References", "===Citations======Bibliography===* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *" ], [ "Further reading", "===Primary sources in English translation===* * * * * * * * * * * * ===Secondary works===* * * * * * * * * * * * * * *" ], [ "External links", "* The Making of Charlemagne's Europe (freely available database of prosopographical and socio-economic data from legal documents dating to Charlemagne's reign, produced by King's College London)* Internet Medieval Sourcebook, a collection of primary sources of Charlemagne's reign edited by Paul Halsall of Fordham University* * * An interactive map of Charlemagne's travels" ] ]

[ [ "Character encodings in HTML" ], [ "Introduction", "While Hypertext Markup Language (HTML) has been in use since 1991, HTML 4.0 from December 1997 was the first standardized version where international characters were given reasonably complete treatment.", "When an HTML document includes special characters outside the range of seven-bit ASCII, two goals are worth considering: the information's integrity, and universal browser display." ], [ "Specifying the document's character encoding", "There are two general ways to specify which character encoding is used in the document.First, the web server can include the character encoding or \"charset\" in the Hypertext Transfer Protocol (HTTP) Content-Type header, which would typically look like this:Content-Type: text/html; charset=utf-8This method gives the HTTP server a convenient way to alter document's encoding according to content negotiation; certain HTTP server software can do it, for example Apache with the module mod_charset_lite.Second, a declaration can be included within the document itself.For HTML it is possible to include this information inside the head element near the top of the document:HTML5 also allows the following syntax to mean exactly the same:XHTML documents have a third option: to express the character encoding via XML declaration, as follows:With this second approach, because the character encoding cannot be known until the declaration is parsed, there is a problem knowing which character encoding is used in the document up to and including the declaration itself.", "If the character encoding is an ASCII extension then the content up to and including the declaration itself should be pure ASCII and this will work correctly.", "For character encodings that are not ASCII extensions (i.e.", "not a superset of ASCII), such as UTF-16BE and UTF-16LE, a processor of HTML, such as a web browser, should be able to parse the declaration in some cases through the use of heuristics.===Encoding detection algorithm===As of HTML5 the recommended charset is UTF-8.An \"encoding sniffing algorithm\" is defined in the specification to determine the character encoding of the document based on multiple sources of input, including:# Explicit user instruction# An explicit meta tag within the first 1024 bytes of the document# A byte order mark (BOM) within the first three bytes of the document# The HTTP Content-Type or other transport layer information# Analysis of the document bytes looking for specific sequences or ranges of byte values, and other tentative detection mechanisms.Characters outside of the printable ASCII range (32 to 126) usually appear incorrectly.", "This presents few problems for English-speaking users, but other languages regularly—in some cases, always—require characters outside that range.", "In Chinese, Japanese, and Korean (CJK) language environments where there are several different multi-byte encodings in use, auto-detection is also often employed.", "Finally, browsers usually permit the user to override ''incorrect'' charset label manually as well.It is increasingly common for multilingual websites and websites in non-Western languages to use UTF-8, which allows use of the same encoding for all languages.", "UTF-16 or UTF-32, which can be used for all languages as well, are less widely used because they can be harder to handle in programming languages that assume a byte-oriented ASCII superset encoding, and they are less efficient for text with a high frequency of ASCII characters, which is usually the case for HTML documents.Successful viewing of a page is not necessarily an indication that its encoding is specified correctly.", "If the page's creator and reader are both assuming some platform-specific character encoding, and the server does not send any identifying information, then the reader will nonetheless see the page as the creator intended, but other readers on different platforms or with different native languages will not see the page as intended." ], [ "Permitted encodings", "The WHATWG Encoding Standard, referenced by recent HTML standards (the current WHATWG HTML Living Standard, as well as the formerly competing W3C HTML 5.0 and 5.1) specifies a list of encodings which browsers must support.", "The HTML standards forbid support of other encodings.", "The Encoding Standard further stipulates that new formats, new protocols (even when existing formats are used) and authors of new documents are required to use UTF-8 exclusively.Besides UTF-8, the following encodings are explicitly listed in the HTML standard itself, with reference to the Encoding Standard:The following additional encodings are listed in the Encoding Standard, and support for them is therefore also required:The following encodings are listed as explicit examples of forbidden encodings:The standard also defines a \"replacement\" decoder, which maps all content labelled as certain encodings to the replacement character (�), refusing to process it at all.", "This is intended to prevent attacks (e.g.", "cross site scripting) which may exploit a difference between the client and server in what encodings are supported in order to mask malicious content.", "Although the same security concern applies to ISO-2022-JP and UTF-16, which also allow sequences of ASCII bytes to be interpreted differently, this approach was not seen as feasible for them since they are comparatively more frequently used in deployed content.", "The following encodings receive this treatment:" ], [ "Character references", "In addition to native character encodings, characters can also be encoded as ''character references'', which can be ''numeric character references'' (decimal or hexadecimal) or ''character entity references''.", "Character entity references are also sometimes referred to as ''named entities'', or ''HTML entities'' for HTML.", "HTML's usage of character references derives from SGML.===HTML character references===A ''numeric character reference'' in HTML refers to a character by its Universal Character Set/Unicode ''code point'', and uses the format:&#''nnnn'';or:&#x''hhhh'';where ''nnnn'' is the code point in decimal form, and ''hhhh'' is the code point in hexadecimal form.", "The ''x'' must be lowercase in XML documents.", "The ''nnnn'' or ''hhhh'' may be any number of digits and may include leading zeros.", "The ''hhhh'' may mix uppercase and lowercase, though uppercase is the usual style.Not all web browsers or email clients used by receivers of HTML documents, or text editors used by authors of HTML documents, will be able to render all HTML characters.", "Most modern software is able to display most or all of the characters for the user's language, and will draw a box or other clear indicator for characters they cannot render.For codes from 0 to 127, the original 7-bit ASCII standard set, most of these characters can be used without a character reference.", "Codes from 160 to 255 can all be created using character entity names.", "Only a few higher-numbered codes can be created using entity names, but all can be created by decimal number character reference.Character entity references can also have the format &''name''; where ''name'' is a case-sensitive alphanumeric string.", "For example, \"λ\" can also be encoded as λ in an HTML document.", "The character entity references <, >, " and & are predefined in HTML and SGML, because , >, \" and & are already used to delimit markup.", "This notably did not include XML's ' (') entity prior to HTML5.For a list of all named HTML character entity references along with the versions in which they were introduced, see List of XML and HTML character entity references.Unnecessary use of HTML character references may significantly reduce HTML readability.", "If the character encoding for a web page is chosen appropriately, then HTML character references are usually only required for markup delimiting characters as mentioned above, and for a few special characters (or none at all if a native Unicode encoding like UTF-8 is used).", "Incorrect HTML entity escaping may also open up security vulnerabilities for injection attacks such as cross-site scripting.", "If HTML attributes are left unquoted, certain characters, most importantly whitespace, such as space and tab, must be escaped using entities.", "Other languages related to HTML have their own methods of escaping characters.===XML character references===Unlike traditional HTML with its large range of character entity references, in XML there are only five predefined character entity references.", "These are used to escape characters that are markup sensitive in certain contexts: & & ampersand U+0026 < > > greater-than sign U+003E " \" quotation mark U+0022 ' ' apostrophe U+0027All other character entity references have to be defined before they can be used.", "For example, use of é (which gives é, Latin lower-case E with acute accent, U+00E9 in Unicode) in an XML document will generate an error unless the entity has already been defined.", "XML also requires that the x in hexadecimal numeric references be in lowercase: for example &#xA1b rather than &#XA1b.", "XHTML, which is an XML application, supports the HTML entity set, along with XML's predefined entities." ], [ "See also", "* Charset sniffing – used by many browsers when character encoding metadata is not available* Unicode and HTML* Language code* List of XML and HTML character entity references" ], [ "References" ], [ "External links", "* Online HTML entity encoder & decoder tool* Character entity references in HTML4* The Definitive Guide to Web Character Encoding* HTML Entity Encoding chapter of Browser Security Handbook – more information about current browsers and their entity handling* The Open Web Application Security Project's wiki article on cross-site scripting (XSS)" ] ]

[ [ "Carbon nanotube" ], [ "Introduction", "A scanning tunneling microscopy image of a single-walled carbon nanotubeRotating single-walled zigzag carbon nanotubeA '''carbon nanotube''' ('''CNT''') is a tube made of carbon with a diameter in the nanometer range (nanoscale).", "They are one of the allotropes of carbon.", "''Single-walled carbon nanotubes'' (''SWCNTs'') have diameters around 0.5–2.0 nanometers, about 100,000 times smaller than the width of a human hair.", "They can be idealized as cutouts from a two-dimensional graphene sheet rolled up to form a hollow cylinder.", "''Multi-walled carbon nanotubes'' (''MWCNTs'') consist of nested single-wall carbon nanotubes in a nested, tube-in-tube structure.", "Double- and triple-walled carbon nanotubes are special cases of MWCNT.Carbon nanotubes can exhibit remarkable properties, such as exceptional tensile strength and thermal conductivity because of their nanostructure and strength of the bonds between carbon atoms.", "Some SWCNT structures exhibit high electrical conductivity while others are semiconductors.", "In addition, carbon nanotubes can be chemically modified.", "These properties are expected to be valuable in many areas of technology, such as electronics, optics, composite materials (replacing or complementing carbon fibers), nanotechnology, and other applications of materials science.The predicted properties for SWCNTs were tantalizing, but a path to synthesizing them was lacking until 1993, when Iijima and Ichihashi at NEC and Bethune et al.", "at IBM independently discovered that co-vaporizing carbon and transition metals such as iron and cobalt could specifically catalyze SWCNT formation.", "These discoveries triggered research that succeeded in greatly increasing the efficiency of the catalytic production technique, and led to an explosion of work to characterize and find applications for SWCNTs." ], [ "Structure of SWNTs", "=== Basic details ===A \"sliced and unrolled\" representation of a carbon nanotube as a strip of a graphene molecule, overlaid on a diagram of the full molecule (faint background).", "The arrow shows the gap ''A2'' where the atom ''A1'' on one edge of the strip would fit in the opposite edge, as the strip is rolled upThe basis vectors '''''u''''' and '''''v''''' of the relevant sub-lattice, the (n,m) pairs that define non-isomorphic carbon nanotube structures (red dots), and the pairs that define the enantiomers of the chiral ones (blue dots)The structure of an ideal (infinitely long) single-walled carbon nanotube is that of a regular hexagonal lattice drawn on an infinite cylindrical surface, whose vertices are the positions of the carbon atoms.", "Since the length of the carbon-carbon bonds is fairly fixed, there are constraints on the diameter of the cylinder and the arrangement of the atoms on it.In the study of nanotubes, one defines a zigzag path on a graphene-like lattice as a path that turns 60 degrees, alternating left and right, after stepping through each bond.", "It is also conventional to define an armchair path as one that makes two left turns of 60 degrees followed by two right turns every four steps.", "On some carbon nanotubes, there is a closed zigzag path that goes around the tube.", "One says that the tube is of the '''zigzag type''' or configuration, or simply is a '''zigzag nanotube'''.", "If the tube is instead encircled by a closed armchair path, it is said to be of the '''armchair type''', or an '''armchair nanotube'''.", "An infinite nanotube that is of the zigzag (or armchair) type consists entirely of closed zigzag (or armchair) paths, connected to each other.The zigzag and armchair configurations are not the only structures that a single-walled nanotube can have.", "To describe the structure of a general infinitely long tube, one should imagine it being sliced open by a cut parallel to its axis, that goes through some atom ''A'', and then unrolled flat on the plane, so that its atoms and bonds coincide with those of an imaginary graphene sheet—more precisely, with an infinitely long strip of that sheet.", "The two halves of the atom ''A'' will end up on opposite edges of the strip, over two atoms ''A1'' and ''A2'' of the graphene.", "The line from ''A1'' to ''A2'' will correspond to the circumference of the cylinder that went through the atom ''A'', and will be perpendicular to the edges of the strip.", "In the graphene lattice, the atoms can be split into two classes, depending on the directions of their three bonds.", "Half the atoms have their three bonds directed the same way, and half have their three bonds rotated 180 degrees relative to the first half.", "The atoms ''A1'' and ''A2'', which correspond to the same atom ''A'' on the cylinder, must be in the same class.", "It follows that the circumference of the tube and the angle of the strip are not arbitrary, because they are constrained to the lengths and directions of the lines that connect pairs of graphene atoms in the same class.Let '''''u''''' and '''''v''''' be two linearly independent vectors that connect the graphene atom ''A1'' to two of its nearest atoms with the same bond directions.", "That is, if one numbers consecutive carbons around a graphene cell with C1 to C6, then '''''u''''' can be the vector from C1 to C3, and '''''v''''' be the vector from C1 to C5.Then, for any other atom ''A2'' with same class as ''A1'', the vector from ''A1'' to ''A2'' can be written as a linear combination ''n'' '''''u''''' + ''m'' '''''v''''', where ''n'' and ''m'' are integers.", "And, conversely, each pair of integers (''n'',''m'') defines a possible position for ''A2''.", "Given ''n'' and ''m'', one can reverse this theoretical operation by drawing the vector '''''w''''' on the graphene lattice, cutting a strip of the latter along lines perpendicular to '''''w''''' through its endpoints ''A1'' and ''A2'', and rolling the strip into a cylinder so as to bring those two points together.", "If this construction is applied to a pair (''k'',0), the result is a zigzag nanotube, with closed zigzag paths of 2''k'' atoms.", "If it is applied to a pair (''k'',''k''), one obtains an armchair tube, with closed armchair paths of 4''k'' atoms." ], [ "Types", "The structure of the nanotube is not changed if the strip is rotated by 60 degrees clockwise around ''A1'' before applying the hypothetical reconstruction above.", "Such a rotation changes the corresponding pair (''n'',''m'') to the pair (−2''m'',''n''+''m'').", "It follows that many possible positions of ''A2'' relative to ''A1'' — that is, many pairs (''n'',''m'') — correspond to the same arrangement of atoms on the nanotube.", "That is the case, for example, of the six pairs (1,2), (−2,3), (−3,1), (−1,−2), (2,−3), and (3,−1).", "In particular, the pairs (''k'',0) and (0,''k'') describe the same nanotube geometry.", "These redundancies can be avoided by considering only pairs (''n'',''m'') such that ''n'' > 0 and ''m'' ≥ 0; that is, where the direction of the vector '''''w''''' lies between those of '''''u''''' (inclusive) and '''''v''''' (exclusive).", "It can be verified that every nanotube has exactly one pair (''n'',''m'') that satisfies those conditions, which is called the tube's '''type'''.", "Conversely, for every type there is a hypothetical nanotube.", "In fact, two nanotubes have the same type if and only if one can be conceptually rotated and translated so as to match the other exactly.", "Instead of the type (''n'',''m''), the structure of a carbon nanotube can be specified by giving the length of the vector '''''w''''' (that is, the circumference of the nanotube), and the angle ''α'' between the directions of '''''u''''' and '''''w''''', may range from 0 (inclusive) to 60 degrees clockwise (exclusive).", "If the diagram is drawn with '''''u''''' horizontal, the latter is the tilt of the strip away from the vertical.=== Chirality and mirror symmetry ===A nanotube is chiral if it has type (''n'',''m''), with ''m'' > 0 and ''m'' ≠ ''n''; then its enantiomer (mirror image) has type (''m'',''n''), which is different from (''n'',''m'').", "This operation corresponds to mirroring the unrolled strip about the line ''L'' through ''A1'' that makes an angle of 30 degrees clockwise from the direction of the '''''u''''' vector (that is, with the direction of the vector '''''u'''''+'''''v''''').", "The only types of nanotubes that are achiral are the (''k'',0) \"zigzag\" tubes and the (''k'',''k'') \"armchair\" tubes.", "If two enantiomers are to be considered the same structure, then one may consider only types (''n'',''m'') with 0 ≤ ''m'' ≤ ''n'' and ''n'' > 0.Then the angle ''α'' between '''''u''''' and '''''w''''', which may range from 0 to 30 degrees (inclusive both), is called the \"chiral angle\" of the nanotube.=== Circumference and diameter ===From ''n'' and ''m'' one can also compute the circumference ''c'', which is the length of the vector '''''w''''', which turns out to be:: in picometres.", "The diameter of the tube is then , that is: also in picometres.", "(These formulas are only approximate, especially for small ''n'' and ''m'' where the bonds are strained; and they do not take into account the thickness of the wall.", ")The tilt angle ''α'' between '''''u''''' and '''''w''''' and the circumference ''c'' are related to the type indices ''n'' and ''m'' by:: where arg(''x'',''y'') is the clockwise angle between the ''X''-axis and the vector (''x'',''y''); a function that is available in many programming languages as atan2(''y'',''x'').", "Conversely, given ''c'' and ''α'', one can get the type (''n'',''m'') by the formulas:: which must evaluate to integers." ], [ "Physical limits", "=== Narrowest examples ===If ''n'' and ''m'' are too small, the structure described by the pair (''n'',''m'') will describe a molecule that cannot be reasonably called a \"tube\", and may not even be stable.", "For example, the structure theoretically described by the pair (1,0) (the limiting \"zigzag\" type) would be just a chain of carbons.", "That is a real molecule, the carbyne; which has some characteristics of nanotubes (such as orbital hybridization, high tensile strength, etc.)", "— but has no hollow space, and may not be obtainable as a condensed phase.", "The pair (2,0) would theoretically yield a chain of fused 4-cycles; and (1,1), the limiting \"armchair\" structure, would yield a chain of bi-connected 4-rings.", "These structures may not be realizable.The thinnest carbon nanotube proper is the armchair structure with type (2,2), which has a diameter of 0.3 nm.", "This nanotube was grown inside a multi-walled carbon nanotube.", "Assigning of the carbon nanotube type was done by a combination of high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, and density functional theory (DFT) calculations.The thinnest ''freestanding'' single-walled carbon nanotube is about 0.43 nm in diameter.", "Researchers suggested that it can be either (5,1) or (4,2) SWCNT, but the exact type of the carbon nanotube remains questionable.", "(3,3), (4,3), and (5,1) carbon nanotubes (all about 0.4 nm in diameter) were unambiguously identified using aberration-corrected high-resolution transmission electron microscopy inside double-walled CNTs.===Length===CycloparaphenyleneThe observation of the ''longest'' carbon nanotubes grown so far, around 0.5 metre (550 mm) long, was reported in 2013.These nanotubes were grown on silicon substrates using an improved chemical vapor deposition (CVD) method and represent electrically uniform arrays of single-walled carbon nanotubes.The ''shortest'' carbon nanotube can be considered to be the organic compound cycloparaphenylene, which was synthesized in 2008 by Ramesh Jasti.", "Other small molecule carbon nanotubes have been synthesized since.===Density===The ''highest density'' of CNTs was achieved in 2013, grown on a conductive titanium-coated copper surface that was coated with co-catalysts cobalt and molybdenum at lower than typical temperatures of 450 °C.", "The tubes averaged a height of 380 nm and a mass density of 1.6 g cm−3.The material showed ohmic conductivity (lowest resistance ~22 kΩ)." ], [ "Variants", "There is no consensus on some terms describing carbon nanotubes in the scientific literature: both \"-wall\" and \"-walled\" are being used in combination with \"single\", \"double\", \"triple\", or \"multi\", and the letter C is often omitted in the abbreviation, for example, multi-walled carbon nanotube (MWNT).", "The International Standards Organization uses single-wall or multi-wall in its documents.=== Multi-walled ===Triple-walled armchair carbon nanotubeMulti-walled nanotubes (MWNTs) consist of multiple rolled layers (concentric tubes) of graphene.", "There are two models that can be used to describe the structures of multi-walled nanotubes.", "In the ''Russian Doll'' model, sheets of graphite are arranged in concentric cylinders, e.g., a (0,8) single-walled nanotube (SWNT) within a larger (0,17) single-walled nanotube.", "In the ''Parchment'' model, a single sheet of graphite is rolled in around itself, resembling a scroll of parchment or a rolled newspaper.", "The interlayer distance in multi-walled nanotubes is close to the distance between graphene layers in graphite, approximately 3.4 Å.", "The Russian Doll structure is observed more commonly.", "Its individual shells can be described as SWNTs, which can be metallic or semiconducting.", "Because of statistical probability and restrictions on the relative diameters of the individual tubes, one of the shells, and thus the whole MWNT, is usually a zero-gap metal.Double-walled carbon nanotubes (DWNTs) form a special class of nanotubes because their morphology and properties are similar to those of SWNTs but they are more resistant to attacks by chemicals.", "This is especially important when it is necessary to graft chemical functions to the surface of the nanotubes (functionalization) to add properties to the CNT.", "Covalent functionalization of SWNTs will break some C=C double bonds, leaving \"holes\" in the structure on the nanotube and thus modifying both its mechanical and electrical properties.", "In the case of DWNTs, only the outer wall is modified.", "DWNT synthesis on the gram-scale by the CCVD technique was first proposed in 2003 from the selective reduction of oxide solutions in methane and hydrogen.The telescopic motion ability of inner shells and their unique mechanical properties will permit the use of multi-walled nanotubes as the main movable arms in upcoming nanomechanical devices.", "The retraction force that occurs to telescopic motion is caused by the Lennard-Jones interaction between shells, and its value is about 1.5 nN.=== Junctions and crosslinking ===Transmission electron microscope image of carbon nanotube junction Junctions between two or more nanotubes have been widely discussed theoretically.", "Such junctions are quite frequently observed in samples prepared by arc discharge as well as by chemical vapor deposition.", "The electronic properties of such junctions were first considered theoretically by Lambin et al., who pointed out that a connection between a metallic tube and a semiconducting one would represent a nanoscale heterojunction.", "Such a junction could therefore form a component of a nanotube-based electronic circuit.", "The adjacent image shows a junction between two multiwalled nanotubes.Junctions between nanotubes and graphene have been considered theoretically and studied experimentally.", "Nanotube-graphene junctions form the basis of pillared graphene, in which parallel graphene sheets are separated by short nanotubes.", "Pillared graphene represents a class of three-dimensional carbon nanotube architectures.3D carbon scaffoldsRecently, several studies have highlighted the prospect of using carbon nanotubes as building blocks to fabricate three-dimensional macroscopic (>100 nm in all three dimensions) all-carbon devices.", "Lalwani et al.", "have reported a novel radical-initiated thermal crosslinking method to fabricate macroscopic, free-standing, porous, all-carbon scaffolds using single- and multi-walled carbon nanotubes as building blocks.", "These scaffolds possess macro-, micro-, and nano-structured pores, and the porosity can be tailored for specific applications.", "These 3D all-carbon scaffolds/architectures may be used for the fabrication of the next generation of energy storage, supercapacitors, field emission transistors, high-performance catalysis, photovoltaics, and biomedical devices, implants, and sensors.=== Other morphologies ===nanobud structureCarbon nanobuds are a newly created material combining two previously discovered allotropes of carbon: carbon nanotubes and fullerenes.", "In this new material, fullerene-like \"buds\" are covalently bonded to the outer sidewalls of the underlying carbon nanotube.", "This hybrid material has useful properties of both fullerenes and carbon nanotubes.", "In particular, they have been found to be exceptionally good field emitters.", "In composite materials, the attached fullerene molecules may function as molecular anchors preventing slipping of the nanotubes, thus improving the composite's mechanical properties.A carbon peapod is a novel hybrid carbon material which traps fullerene inside a carbon nanotube.", "It can possess interesting magnetic properties with heating and irradiation.", "It can also be applied as an oscillator during theoretical investigations and predictions.In theory, a nanotorus is a carbon nanotube bent into a torus (doughnut shape).", "Nanotori are predicted to have many unique properties, such as magnetic moments 1000 times larger than that previously expected for certain specific radii.", "Properties such as magnetic moment, thermal stability, etc.", "vary widely depending on the radius of the torus and the radius of the tube.Graphenated carbon nanotubes are a relatively new hybrid that combines graphitic foliates grown along the sidewalls of multiwalled or bamboo-style CNTs.", "The foliate density can vary as a function of deposition conditions (e.g., temperature and time) with their structure ranging from a few layers of graphene (< 10) to thicker, more graphite-like.", "The fundamental advantage of an integrated graphene-CNT structure is the high surface area three-dimensional framework of the CNTs coupled with the high edge density of graphene.", "Depositing a high density of graphene foliates along the length of aligned CNTs can significantly increase the total charge capacity per unit of nominal area as compared to other carbon nanostructures.Cup-stacked carbon nanotubes (CSCNTs) differ from other quasi-1D carbon structures, which normally behave as quasi-metallic conductors of electrons.", "CSCNTs exhibit semiconducting behavior because of the stacking microstructure of graphene layers." ], [ "Properties", "Many properties of single-walled carbon nanotubes depend significantly on the (''n'',''m'') type, and this dependence is non-monotonic (see Kataura plot).", "In particular, the band gap can vary from zero to about 2 eV and the electrical conductivity can show metallic or semiconducting behavior.=== Mechanical ===A scanning electron microscopy image of carbon nanotube bundlesCarbon nanotubes are the strongest and stiffest materials yet discovered in terms of tensile strength and elastic modulus.", "This strength results from the covalent sp2 bonds formed between the individual carbon atoms.", "In 2000, a multiwalled carbon nanotube was tested to have a tensile strength of .", "(For illustration, this translates into the ability to endure tension of a weight equivalent to on a cable with cross-section of ).", "Further studies, such as one conducted in 2008, revealed that individual CNT shells have strengths of up to ≈, which is in agreement with quantum/atomistic models.", "Because carbon nanotubes have a low density for a solid of 1.3 to 1.4 g/cm3, its specific strength of up to 48,000 kN·m/kg is the best of known materials, compared to high-carbon steel's 154 kN·m/kg.Although the strength of individual CNT shells is extremely high, weak shear interactions between adjacent shells and tubes lead to significant reduction in the effective strength of multiwalled carbon nanotubes and carbon nanotube bundles down to only a few GPa.", "This limitation has been recently addressed by applying high-energy electron irradiation, which crosslinks inner shells and tubes, and effectively increases the strength of these materials to ≈60 GPa for multiwalled carbon nanotubes and ≈17 GPa for double-walled carbon nanotube bundles.", "CNTs are not nearly as strong under compression.", "Because of their hollow structure and high aspect ratio, they tend to undergo buckling when placed under compressive, torsional, or bending stress.On the other hand, there was evidence that in the radial direction they are rather soft.", "The first transmission electron microscope observation of radial elasticity suggested that even van der Waals forces can deform two adjacent nanotubes.", "Later, nanoindentations with an atomic force microscope were performed by several groups to quantitatively measure the radial elasticity of multiwalled carbon nanotubes and tapping/contact mode atomic force microscopy was also performed on single-walled carbon nanotubes.", "Young's modulus of on the order of several GPa showed that CNTs are in fact very soft in the radial direction.It was reported in 2020, that CNT-filled polymer nanocomposites with 4 wt% and 6 wt% loadings are the most optimal concentrations, as they provide a good balance between mechanical properties and resilience of mechanical properties against UV exposure for the offshore umbilical sheathing layer.=== Electrical ===Band structures computed using a tight binding approximation for (6,0) CNT (zigzag, metallic), (10,2) CNT (semiconducting) and (10,10) CNT (armchair, metallic)Unlike graphene, which is a two-dimensional semimetal, carbon nanotubes are either metallic or semiconducting along the tubular axis.", "For a given (''n'',''m'') nanotube, if ''n'' = ''m'', the nanotube is metallic; if ''n'' − ''m'' is a multiple of 3 and n ≠ m, then the nanotube is quasi-metallic with a very small band gap, otherwise the nanotube is a moderate semiconductor.Thus, all armchair (''n'' = ''m'') nanotubes are metallic, and nanotubes (6,4), (9,1), etc.", "are semiconducting.Carbon nanotubes are not semimetallic because the degenerate point (the point where the π bonding band meets the π* anti-bonding band, at which the energy goes to zero) is slightly shifted away from the ''K'' point in the Brillouin zone because of the curvature of the tube surface, causing hybridization between the σ* and π* anti-bonding bands, modifying the band dispersion.The rule regarding metallic versus semiconductor behavior has exceptions because curvature effects in small-diameter tubes can strongly influence electrical properties.", "Thus, a (5,0) SWCNT that should be semiconducting in fact is metallic according to the calculations.", "Likewise, zigzag and chiral SWCNTs with small diameters that should be metallic have a finite gap (armchair nanotubes remain metallic).", "In theory, metallic nanotubes can carry an electric current density of 4 × 109 A/cm2, which is more than 1,000 times greater than those of metals such as copper, where for copper interconnects, current densities are limited by electromigration.", "Carbon nanotubes are thus being explored as interconnects and conductivity-enhancing components in composite materials, and many groups are attempting to commercialize highly conducting electrical wire assembled from individual carbon nanotubes.", "There are significant challenges to be overcome however, such as undesired current saturation under voltage, and the much more resistive nanotube-to-nanotube junctions and impurities, all of which lower the electrical conductivity of the macroscopic nanotube wires by orders of magnitude, as compared to the conductivity of the individual nanotubes.Because of its nanoscale cross-section, electrons propagate only along the tube's axis.", "As a result, carbon nanotubes are frequently referred to as one-dimensional conductors.", "The maximum electrical conductance of a single-walled carbon nanotube is 2''G''0, where ''G''0 = 2''e''2/''h'' is the conductance of a single ballistic quantum channel.Because of the role of the π-electron system in determining the electronic properties of graphene, doping in carbon nanotubes differs from that of bulk crystalline semiconductors from the same group of the periodic table (e.g., silicon).", "Graphitic substitution of carbon atoms in the nanotube wall by boron or nitrogen dopants leads to p-type and n-type behavior, respectively, as would be expected in silicon.", "However, some non-substitutional (intercalated or adsorbed) dopants introduced into a carbon nanotube, such as alkali metals and electron-rich metallocenes, result in n-type conduction because they donate electrons to the π-electron system of the nanotube.", "By contrast, π-electron acceptors such as FeCl3 or electron-deficient metallocenes function as p-type dopants because they draw π-electrons away from the top of the valence band.Intrinsic superconductivity has been reported, although other experiments found no evidence of this, leaving the claim a subject of debate.In 2021, Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT, published department findings on the use of carbon nanotubes to create an electric current.", "By immersing the structures in an organic solvent, the liquid drew electrons out of the carbon particles.", "Strano was quoted as saying, \"This allows you to do electrochemistry, but with no wires,\" and represents a significant breakthrough in the technology.", "Future applications include powering micro- or nanoscale robots, as well as driving alcohol oxidation reactions, which are important in the chemicals industry.Crystallographic defects also affect the tube's electrical properties.", "A common result is lowered conductivity through the defective region of the tube.", "A defect in metallic armchair-type tubes (which can conduct electricity) can cause the surrounding region to become semiconducting, and single monatomic vacancies induce magnetic properties.=== Optical ===Carbon nanotubes have useful absorption, photoluminescence (fluorescence), and Raman spectroscopy properties.", "Spectroscopic methods offer the possibility of quick and non-destructive characterization of relatively large amounts of carbon nanotubes.", "There is a strong demand for such characterization from the industrial point of view: numerous parameters of nanotube synthesis can be changed, intentionally or unintentionally, to alter the nanotube quality, such as the non-tubular carbon content, structure (chirality) of the produced nanotubes, and structural defects.", "These features then determine nearly all other significant optical, mechanical, and electrical properties.Carbon nanotube optical properties have been explored for use in applications such as for light-emitting diodes (LEDs) and photo-detectors based on a single nanotube have been produced in the lab.", "Their unique feature is not the efficiency, which is yet relatively low, but the narrow selectivity in the wavelength of emission and detection of light and the possibility of its fine-tuning through the nanotube structure.", "In addition, bolometer and optoelectronic memory devices have been realised on ensembles of single-walled carbon nanotubes.", "Nanotube fluorescence has been investigated for the purposes of imaging and sensing in biomedical applications.=== Thermal ===All nanotubes are expected to be very good thermal conductors along the tube, exhibiting a property known as \"ballistic conduction\", but good insulators lateral to the tube axis.", "Measurements show that an individual SWNT has a room-temperature thermal conductivity along its axis of about 3500 W·m−1·K−1; compare this to copper, a metal well known for its good thermal conductivity, which transmits 385 W·m−1·K−1.An individual SWNT has a room-temperature thermal conductivity lateral to its axis (in the radial direction) of about 1.52 W·m−1·K−1, which is about as thermally conductive as soil.", "Macroscopic assemblies of nanotubes such as films or fibres have reached up to 1500 W·m−1·K−1 so far.", "Networks composed of nanotubes demonstrate different values of thermal conductivity, from the level of thermal insulation with the thermal conductivity of 0.1 W·m−1·K−1 to such high values.", "That is dependent on the amount of contribution to the thermal resistance of the system caused by the presence of impurities, misalignments and other factors.", "The temperature stability of carbon nanotubes is estimated to be up to 2800 °C in vacuum and about 750 °C in air.Crystallographic defects strongly affect the tube's thermal properties.", "Such defects lead to phonon scattering, which in turn increases the relaxation rate of the phonons.", "This reduces the mean free path and reduces the thermal conductivity of nanotube structures.", "Phonon transport simulations indicate that substitutional defects such as nitrogen or boron will primarily lead to the scattering of high-frequency optical phonons.", "However, larger-scale defects such as Stone–Wales defects cause phonon scattering over a wide range of frequencies, leading to a greater reduction in thermal conductivity." ], [ "Synthesis", "Techniques have been developed to produce nanotubes in sizeable quantities, including arc discharge, laser ablation, chemical vapor deposition (CVD) and high-pressure carbon monoxide disproportionation (HiPCO).", "Among these arc discharge, laser ablation are batch by batch process, Chemical Vapor Deposition can be used both for batch by batch or continuous processes, and HiPCO is gas phase continuous process.", "Most of these processes take place in a vacuum or with process gases.", "The CVD growth method is popular, as it yields high quantity and has a degree of control over diameter, length and morphology.", "Using particulate catalysts, large quantities of nanotubes can be synthesized by these methods, and industrialisation is well on its way, with several CNT and CNT fibers factory around the world.", "One problem of CVD processes is the high variability in the nanotube's characteristics The HiPCO process advances in catalysis and continuous growth are making CNTs more commercially viable.", "The HiPCO process helps in producing high purity single-walled carbon nanotubes in higher quantity.", "The HiPCO reactor operates at high temperature 900-1100 °C and high pressure ~30-50 bar.", "It uses carbon monoxide as the carbon source and iron pentacarbonyl or nickel tetracarbonyl as a catalyst.", "These catalysts provide a nucleation site for the nanotubes to grow, while cheaper iron-based catalysts like Ferrocene can be used for CVD process.Vertically aligned carbon nanotube arrays are also grown by thermal chemical vapor deposition.", "A substrate (quartz, silicon, stainless steel, carbon fibers, etc.)", "is coated with a catalytic metal (Fe, Co, Ni) layer.", "Typically that layer is iron and is deposited via sputtering to a thickness of 1–5 nm.", "A 10–50 nm underlayer of alumina is often also put down on the substrate first.", "This imparts controllable wetting and good interfacial properties.When the substrate is heated to the growth temperature (~600 to 850 °C), the continuous iron film breaks up into small islands with each island then nucleating a carbon nanotube.", "The sputtered thickness controls the island size and this in turn determines the nanotube diameter.", "Thinner iron layers drive down the diameter of the islands and drive down the diameter of the nanotubes grown.", "The amount of time the metal island can sit at the growth temperature is limited as they are mobile and can merge into larger (but fewer) islands.", "Annealing at the growth temperature reduces the site density (number of CNT/mm2) while increasing the catalyst diameter.The as-prepared carbon nanotubes always have impurities such as other forms of carbon (amorphous carbon, fullerene, etc.)", "and non-carbonaceous impurities (metal used for catalyst).", "These impurities need to be removed to make use of the carbon nanotubes in applications." ], [ "Purification", "As-synthesized carbon nanotubes typically contain impurities and most importantly different chiralities of carbon nanotubes.", "Therefore, multiple methods have been developed to purify them including polymer-assisted, density gradient ultracentrifugation (DGU), chromatography and aqueous two-phase extraction (ATPE).", "These methods have been reviewed in multiple articles.Certain polymers selectively disperse or wrap CNTs of a particular chirality, metallic character or diameter.", "For example, poly(phenylenevinylenes) disperses CNTs of specific diameters (0.75–0.84 nm) and polyfluorenes are highly selective for semiconducting CNTs.", "It involves mainly two steps, sonicate the mixture (CNTs and polymers in solvent), centrifuge and the supernatant are desired CNTs.Density gradient ultracentrifugation is a method based on the density difference of CNTs, so that different components are layered in centrifuge tubes under centrifugal force.", "Chromatography-based methods include size exclusion (SEC), ion-exchange (IEX) and gel chromatography.", "For SEC, CNTs are separated due to the difference in size using a stationary phase with different pore size.", "As for IEX, the separation is achieved based on their differential adsorption and desorption onto chemically functionalized resins packed in an IEX column, so understanding the interaction between CNTs mixtures and resins is important.", "The first IEX is reported to separate DNA-SWCNTs.", "Gel chromatography is based on the partition of CNTs between stationary and mobile phase, it's found semiconducting CNTs are more strongly attracted by gel than metallic CNTs.", "While it shows potential, the current application is limited to the separation of semiconducting (n,m) species.ATPE is a very simple but powerful approach and.", "It uses two water-soluble polymers such as polyethylene glycol (PEG) and dextran.", "When mixed, two immiscible aqueous phases form spontaneously, and each of the two phases shows a different affinity to CNTs.", "Partition depends on the solvation energy difference between two similar phases of microscale volumes.", "By changing the separation system or temperatures, and adding strong oxidants, reductants, or salts, the partition of CNTs species into the two phases can be adjusted.Despite the progress that has been made to separate and purify CNTs, many challenges remain, such as the growth of chirality-controlled CNTs, so that no further purification is needed, or large-scale purification.=== Advantages of monochiral ===Monochiral CNTs have the advantage that they do contain less or no impurities, well-defined non-congested optical spectra.", "This allows to create for example CNT-based biosensors with higher sensitivity and selectivity.", "For example, monochiral SWCNTs are necessary for multiplexed and ratiometric sensing schemes, enhanced sensitivity of biocompatibility." ], [ "Functionalization", "CNTs are known to have weak dispersibility in many solvents such as water as a consequence of strong intermolecular p–p interactions.", "This hinders the processability of CNTs in industrial applications.", "To tackle the issue, various techniques have been developed to modify the surface of CNTs in order to improve their stability and solubility in water.", "This enhances the processing and manipulation of insoluble CNTs rendering them useful for synthesizing innovative CNT nanofluids with impressive properties that are tunable for a wide range of applications.Chemical routes such as covalent functionalization have been studied extensively, which involves the oxidation of CNTs via strong acids (e.g.", "sulfuric acid, nitric acid, or a mixture of both) in order to set the carboxylic groups onto the surface of the CNTs as the final product or for further modification by esterification or amination.", "Free radical grafting is a promising technique among covalent functionalization methods, in which alkyl or aryl peroxides, substituted anilines, and diazonium salts are used as the starting agents.Free radical grafting of macromolecules (as the functional group) onto the surface of CNTs can improve the solubility of CNTs compared to common acid treatments which involve the attachment of small molecules such as hydroxyl onto the surface of CNTs.", "The solubility of CNTs can be improved significantly by free-radical grafting because the large functional molecules facilitate the dispersion of CNTs in a variety of solvents even at a low degree of functionalization.", "Recently an innovative environmentally friendly approach has been developed for the covalent functionalization of multi-walled carbon nanotubes (MWCNTs) using clove buds.", "This approach is innovative and green because it does not use toxic and hazardous acids which are typically used in common carbon nanomaterial functionalization procedures.", "The MWCNTs are functionalized in one pot using a free radical grafting reaction.", "The clove-functionalized MWCNTs are then dispersed in water producing a highly stable multi-walled carbon nanotube aqueous suspension (nanofluids)." ], [ "Modeling", "Computer simulated microstructures with agglomeration regionsCarbon nanotubes are modelled in a similar manner as traditional composites in which a reinforcement phase is surrounded by a matrix phase.", "Ideal models such as cylindrical, hexagonal and square models are common.", "The size of the micromechanics model is highly function of the studied mechanical properties.", "The concept of representative volume element (RVE) is used to determine the appropriate size and configuration of the computer model to replicate the actual behavior of the CNT-reinforced nanocomposite.", "Depending on the material property of interest (thermal, electrical, modulus, creep), one RVE might predict the property better than the alternatives.", "While the implementation of the ideal model is computationally efficient, they do not represent microstructural features observed in scanning electron microscopy of actual nanocomposites.", "To incorporate realistic modeling, computer models are also generated to incorporate variability such as waviness, orientation and agglomeration of multiwall or single-wall carbon nanotubes." ], [ "Metrology", "There are many metrology standards and reference materials available for carbon nanotubes.For single-wall carbon nanotubes, ISO/TS 10868 describes a measurement method for the diameter, purity, and fraction of metallic nanotubes through optical absorption spectroscopy, while ISO/TS 10797 and ISO/TS 10798 establish methods to characterize the morphology and elemental composition of single-wall carbon nanotubes, using transmission electron microscopy and scanning electron microscopy respectively, coupled with energy dispersive X-ray spectrometry analysis.NIST SRM 2483 is a soot of single-wall carbon nanotubes used as a reference material for elemental analysis, and was characterized using thermogravimetric analysis, prompt gamma activation analysis, induced neutron activation analysis, inductively coupled plasma mass spectroscopy, resonant Raman scattering, UV-visible-near infrared fluorescence spectroscopy and absorption spectroscopy, scanning electron microscopy, and transmission electron microscopy.", "The Canadian National Research Council also offers a certified reference material SWCNT-1 for elemental analysis using neutron activation analysis and inductively coupled plasma mass spectroscopy.", "NIST RM 8281 is a mixture of three lengths of single-wall carbon nanotube.For multiwall carbon nanotubes, ISO/TR 10929 identifies the basic properties and the content of impurities, while ISO/TS 11888 describes morphology using scanning electron microscopy, transmission electron microscopy, viscometry, and light scattering analysis.", "ISO/TS 10798 is also valid for multiwall carbon nanotubes." ], [ "Chemical modification", "Carbon nanotubes can be functionalized to attain desired properties that can be used in a wide variety of applications.", "The two main methods of carbon nanotube functionalization are covalent and non-covalent modifications.", "Because of their apparent hydrophobic nature, carbon nanotubes tend to agglomerate hindering their dispersion in solvents or viscous polymer melts.", "The resulting nanotube bundles or aggregates reduce the mechanical performance of the final composite.", "The surface of the carbon nanotubes can be modified to reduce the hydrophobicity and improve interfacial adhesion to a bulk polymer through chemical attachment.The surface of carbon nanotubes can be chemically modified by coating spinel nanoparticles by hydrothermal synthesis and can be used for water oxidation purposes.In addition, the surface of carbon nanotubes can be fluorinated or halofluorinated by heating while in contact with a fluoroorganic substance, thereby forming partially fluorinated carbons (so-called Fluocar materials) with grafted (halo)fluoroalkyl functionality." ], [ "Applications", "Nano tape Carbon nanotubes are currently used in multiple industrial and consumer applications.", "These include battery components, polymer composites, to improve the mechanical, thermal and electrical properties of the bulk product, and as a highly absorptive black paint.", "Many other applications are under development, including field effect transistors for electronics, high-strength fabrics, biosensors for biomedical and agricultural applications, and many others.=== '''Biosensing''' ===SWCNTs have nanoscale dimensions that fit to the size of biological species.", "Due to this size compatibility and their large surface-to-volume ratio, they are sensitive to changes in their chemical environment.", "Through covalent and non-covalent surface functionalization, SWCNTs can be precisely tailored for selective molecular interactions with a target analyte.", "The SWCNT represents the transduction unit that converts the interaction into a signal change (optical or electrical).", "Due to continuous progress in the development of detection strategies, there are numerous examples of the use of SWCNTs as highly sensitive nanosensors (even down to the single molecule level) for a variety of important biomolecules.", "Examples include the detection of reactive oxygen and nitrogen species, neurotransmitters, other small molecules, lipids, proteins, sugars, DNA/RNA, enzymes as well as bacteria.", "Potential future applications include biomedical and environmental applications such as monitoring plant health in agriculture, standoff process control in bioreactors, research/diagnostics of neuronal communication and numerous diseases such as coagulation disorders, diabetes, cancer, microbial and viral infections, testing the efficacy of pharmaceuticals or infection monitoring using smart implants.", "In industry, SWCNTs are already used as sensors in the detection of gases and odors in the form of an electronic nose or in enzyme screening.Optical biosensors with SWCNTs.", "The functionalization of SWCNTs with (bio)polymers leads to nanosensors for various molecules.", "The interaction with these molecules influences the NIR fluorescence of the SWCNTs.The signal change manifests itself in an increase or decrease in the current (electrical) or in a change in the intensity or wavelength of the fluorescence emission (optical).", "Depending on the type of application, both electrical or optical signal transmission can be advantageous.", "For sensitive measurement of electronic changes, field-effect transistors (FET) are often used in which the flow of charges within the SWCNTs is measured.", "The FET structures allow easy on-chip integration and can be parallelized to detect multiple target analytes simultaneously.", "However, such sensors are more invasive for in vivo applications, as the entire device has to be inserted into the body.", "Optical detection with semiconducting SWCNTs is based on the radiative recombination of excitons in the near-infrared (NIR) by prior optical (fluorescence) or electrical excitation (electroluminescence).", "The emission in the NIR enables detection in the biological transparency window, where optical sensor applications benefit from reduced scattering and autofluorescence of biological samples and consequently a high signal-to-noise ratio.", "Compared to optical sensors in the UV or visible range, the penetration depth in biological tissue is also increased.", "In addition to the advantage of a contactless readout SWCNTs have excellent photostability, which enables long-term sensor applications.", "Furthermore, the nanoscale size of SWCNTs allows dense coating of surfaces which enables chemical imaging, e.g.", "of cellular release processes with high spatial and temporal resolution.", "Detection of several target analytes is possible by the spatial arrangement of different SWCNT sensors in arrays or by hyperspectral detection based on monochiral SWCNT sensors that emit at different emission wavelengths.", "For fluorescence applications, however, optical filters to distinguish between excitation and emission and a NIR-sensitive detector must be used.", "Standard silicon detectors can also be used if monochiral SWCNTs (extractable by special purification processes) emitting closer to the visible range (800 - 900 nm) are used.", "In order to avoid susceptibility of optical sensors to fluctuating ambient light, internal references such as SWCNTs that are modified to be non-responsive or stable NIR emitters can be used.", "An alternative is to measure fluorescence lifetimes instead of fluorescence intensities.", "Overall, SWCNTs therefore have great potential as building blocks for various biosensors.To render SWCNTs suitable for biosensing, their surface needs to be modified to ensure colloidal stability and provide a handle for biological recognition.", "Therefore, biosensing and surface modifications (functionalization) are closely related." ], [ "Current industrial applications", "* Easton-Bell Sports, Inc. have been in partnership with Zyvex Performance Materials, using CNT technology in a number of their bicycle components – including flat and riser handlebars, cranks, forks, seatposts, stems and aero bars.", "* Amroy Europe Oy manufactures Hybtonite carbon nano-epoxy resins where carbon nanotubes have been chemically activated to bond to epoxy, resulting in a composite material that is 20% to 30% stronger than other composite materials.", "It has been used for wind turbines, marine paints and a variety of sports gear such as skis, ice hockey sticks, baseball bats, hunting arrows, and surfboards.", "* Surrey NanoSystems synthesizes carbon nanotubes to create vantablack ultra-absorptive black paint.", "* \"Gecko tape\" (also called \"nano tape\") is often commercially sold as double-sided adhesive tape.", "It can be used to hang lightweight items such as pictures and decorative items on smooth walls without punching holes in the wall.", "The carbon nanotube arrays comprising the synthetic setae leave no residue after removal and can stay sticky in extreme temperatures.", "* Tips for atomic force microscope probes.===Applications under development===Applications of nanotubes in development in academia and industry include:* Utilizing carbon nanotubes as the channel material of carbon nanotube field-effect transistors.", "* Using carbon nanotubes as a scaffold for diverse microfabrication techniques.", "* Energy dissipation in self-organized nanostructures under the influence of an electric field.", "* Using carbon nanotubes for environmental monitoring due to their active surface area and their ability to absorb gases.", "*Jack Andraka used carbon nanotubes in his pancreatic cancer test.", "His method of testing won the Intel International Science and Engineering Fair Gordon E. Moore Award in the spring of 2012.", "* The Boeing Company has patented the use of carbon nanotubes for structural health monitoring of composites used in aircraft structures.", "This technology will greatly reduce the risk of an in-flight failure caused by structural degradation of aircraft.", "* Zyvex Technologies has also built a 54' maritime vessel, the Piranha Unmanned Surface Vessel, as a technology demonstrator for what is possible using CNT technology.", "CNTs help improve the structural performance of the vessel, resulting in a lightweight 8,000 lb boat that can carry a payload of 15,000 lb over a range of 2,500 miles.", "* IMEC is using carbon nanotubes for pellicles in semiconductor lithography.", "* In tissue engineering, carbon nanotubes have been used as scaffolding for bone growth.Carbon nanotubes can serve as additives to various structural materials.", "For instance, nanotubes form a tiny portion of the material(s) in some (primarily carbon fiber) baseball bats, golf clubs, car parts, or damascus steel.IBM expected carbon nanotube transistors to be used on Integrated Circuits by 2020.=== Potential/Future ===The strength and flexibility of carbon nanotubes makes them of potential use in controlling other nanoscale structures, which suggests they will have an important role in nanotechnology engineering.", "The highest tensile strength of an individual multi-walled carbon nanotube has been tested to be 63 GPa.", "Carbon nanotubes were found in Damascus steel from the 17th century, possibly helping to account for the legendary strength of the swords made of it.", "Recently, several studies have highlighted the prospect of using carbon nanotubes as building blocks to fabricate three-dimensional macroscopic (>1mm in all three dimensions) all-carbon devices.", "Lalwani et al.", "have reported a novel radical initiated thermal crosslinking method to fabricated macroscopic, free-standing, porous, all-carbon scaffolds using single- and multi-walled carbon nanotubes as building blocks.", "These scaffolds possess macro-, micro-, and nano- structured pores and the porosity can be tailored for specific applications.", "These 3D all-carbon scaffolds/architectures may be used for the fabrication of the next generation of energy storage, supercapacitors, field emission transistors, high-performance catalysis, photovoltaics, and biomedical devices and implants.CNTs are potential candidates for future via and wire material in nano-scale VLSI circuits.", "Eliminating electromigration reliability concerns that plague today's Cu interconnects, isolated (single and multi-wall) CNTs can carry current densities in excess of 1000 MA/cm2 without electromigration damage.Single-walled nanotubes are likely candidates for miniaturizing electronics.", "The most basic building block of these systems is an electric wire, and SWNTs with diameters of an order of a nanometre can be excellent conductors.", "One useful application of SWNTs is in the development of the first intermolecular field-effect transistors (FET).", "The first intermolecular logic gate using SWCNT FETs was made in 2001.A logic gate requires both a p-FET and an n-FET.", "Because SWNTs are p-FETs when exposed to oxygen and n-FETs otherwise, it is possible to expose half of an SWNT to oxygen and protect the other half from it.", "The resulting SWNT acts as a ''not'' logic gate with both p- and n-type FETs in the same molecule.Large quantities of pure CNTs can be made into a freestanding sheet or film by surface-engineered tape-casting (SETC) fabrication technique which is a scalable method to fabricate flexible and foldable sheets with superior properties.", "Another reported form factor is CNT fiber (a.k.a.", "filament) by wet spinning.", "The fiber is either directly spun from the synthesis pot or spun from pre-made dissolved CNTs.", "Individual fibers can be turned into a yarn.", "Apart from its strength and flexibility, the main advantage is making an electrically conducting yarn.", "The electronic properties of individual CNT fibers (i.e.", "bundle of individual CNT) are governed by the two-dimensional structure of CNTs.", "The fibers were measured to have a resistivity only one order of magnitude higher than metallic conductors at .", "By further optimizing the CNTs and CNT fibers, CNT fibers with improved electrical properties could be developed.CNT-based yarns are suitable for applications in energy and electrochemical water treatment when coated with an ion-exchange membrane.", "Also, CNT-based yarns could replace copper as a winding material.", "Pyrhönen et al.", "(2015) have built a motor using CNT winding." ], [ "Safety and health", "The National Institute for Occupational Safety and Health (NIOSH) is the leading United States federal agency conducting research and providing guidance on the occupational safety and health implications and applications of nanomaterials.", "Early scientific studies have indicated that nanoscale particles may pose a greater health risk than bulk materials due to a relative increase in surface area per unit mass.", "Increase in length and diameter of CNT is correlated to increased toxicity and pathological alterations in lung.", "The biological interactions of nanotubes are not well understood, and the field is open to continued toxicological studies.", "It is often difficult to separate confounding factors, and since carbon is relatively biologically inert, some of the toxicity attributed to carbon nanotubes may be instead due to residual metal catalyst contamination.", "In previous studies, only Mitsui-7 was reliably demonstrated to be carcinogenic, although for unclear/unknown reasons.", "Unlike many common mineral fibers (such as asbestos), most SWCNTs and MWCNTs do not fit the size and aspect-ratio criteria to be classified as respirable fibers.", "In 2013, given that the long-term health effects have not yet been measured, NIOSH published a Current Intelligence Bulletin detailing the potential hazards and recommended exposure limit for carbon nanotubes and fibers.", "The U.S. National Institute for Occupational Safety and Health has determined non-regulatory recommended exposure limits (RELs) of 1 μg/m3 for carbon nanotubes and carbon nanofibers as background-corrected elemental carbon as an 8-hour time-weighted average (TWA) respirable mass concentration.", "Although CNT caused pulmonary inflammation and toxicity in mice, exposure to aerosols generated from sanding of composites containing polymer-coated MWCNTs, representative of the actual end-product, did not exert such toxicity.As of October 2016, single-wall carbon nanotubes have been registered through the European Union's Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulations, based on evaluation of the potentially hazardous properties of SWCNT.", "Based on this registration, SWCNT commercialization is allowed in the EU up to 10 metric tons.", "Currently, the type of SWCNT registered through REACH is limited to the specific type of single-wall carbon nanotubes manufactured by OCSiAl, which submitted the application." ], [ "History", "The true identity of the discoverers of carbon nanotubes is a subject of some controversy.", "A 2006 editorial written by Marc Monthioux and Vladimir Kuznetsov in the journal ''Carbon'' described the origin of the carbon nanotube.", "A large percentage of academic and popular literature attributes the discovery of hollow, nanometre-size tubes composed of graphitic carbon to Sumio Iijima of NEC in 1991.His paper initiated a flurry of excitement and could be credited with inspiring the many scientists now studying applications of carbon nanotubes.", "Though Iijima has been given much of the credit for discovering carbon nanotubes, it turns out that the timeline of carbon nanotubes goes back much further than 1991.In 1952, L. V. Radushkevich and V. M. Lukyanovich published clear images of 50-nanometre diameter tubes made of carbon in the ''Journal of Physical Chemistry Of Russia''.", "This discovery was largely unnoticed, as the article was published in Russian, and Western scientists' access to Soviet press was limited during the Cold War.", "Monthioux and Kuznetsov mentioned in their ''Carbon'' editorial: In 1976, Morinobu Endo of CNRS observed hollow tubes of rolled up graphite sheets synthesised by a chemical vapour-growth technique.", "The first specimens observed would later come to be known as single-walled carbon nanotubes (SWNTs).", "Endo, in his early review of vapor-phase-grown carbon fibers (VPCF), also reminded us that he had observed a hollow tube, linearly extended with parallel carbon layer faces near the fiber core.", "This appears to be the observation of multi-walled carbon nanotubes at the center of the fiber.", "The mass-produced MWCNTs today are strongly related to the VPGCF developed by Endo.", "In fact, they call it the \"Endo-process\", out of respect for his early work and patents.", "In 1979, John Abrahamson presented evidence of carbon nanotubes at the 14th Biennial Conference of Carbon at Pennsylvania State University.", "The conference paper described carbon nanotubes as carbon fibers that were produced on carbon anodes during arc discharge.", "A characterization of these fibers was given, as well as hypotheses for their growth in a nitrogen atmosphere at low pressures.In 1981, a group of Soviet scientists published the results of chemical and structural characterization of carbon nanoparticles produced by a thermocatalytic disproportionation of carbon monoxide.", "Using TEM images and XRD patterns, the authors suggested that their \"carbon multi-layer tubular crystals\" were formed by rolling graphene layers into cylinders.", "They speculated that via this rolling, many different arrangements of graphene hexagonal nets are possible.", "They suggested two such possible arrangements: a circular arrangement (armchair nanotube); and a spiral, helical arrangement (chiral tube).In 1987, Howard G. Tennent of Hyperion Catalysis was issued a U.S. patent for the production of \"cylindrical discrete carbon fibrils\" with a \"constant diameter between about 3.5 and about 70 nanometers..., length 102 times the diameter, and an outer region of multiple essentially continuous layers of ordered carbon atoms and a distinct inner core....\"Helping to create the initial excitement associated with carbon nanotubes were Iijima's 1991 discovery of multi-walled carbon nanotubes in the insoluble material of arc-burned graphite rods; and Mintmire, Dunlap, and White's independent prediction that if single-walled carbon nanotubes could be made, they would exhibit remarkable conducting properties.", "Nanotube research accelerated greatly following the independent discoveries by Iijima and Ichihashi at NEC and Bethune ''et al.''", "at IBM of methods to specifically produce ''single-walled'' carbon nanotubes by adding transition-metal catalysts to the carbon in an arc discharge.", "Thess et al.", "refined this catalytic method by vaporizing the carbon/transition-metal combination in a high-temperature furnace, which greatly improved the yield and purity of the SWNTs and made them widely available for characterization and application experiments.", "The arc discharge technique, well known to produce the famed Buckminsterfullerene , thus played a role in the discoveries of both multi- and single-wall nanotubes, extending the run of serendipitous discoveries relating to fullerenes.", "The discovery of nanotubes remains a contentious issue.", "Many believe that Iijima's report in 1991 is of particular importance because it brought carbon nanotubes into the awareness of the scientific community as a whole.In 2020, during an archaeological excavation of Keezhadi in Tamil Nadu, India, ~2600-year-old pottery was discovered whose coatings appear to contain carbon nanotubes.", "The robust mechanical properties of the nanotubes are partially why the coatings have lasted for so many years, say the scientists." ], [ "See also", "* Buckypaper* Carbide-derived carbon* Carbon nanocone* Carbon nanofibers* Carbon nanoscrolls* Carbon nanotube computer* Carbon nanotubes in photovoltaics* Colossal carbon tube* Diamond nanothread* Filamentous carbon* Molecular modelling* Nanoflower* Ninithi (nanotube modelling software)* Optical properties of carbon nanotubes* Organic semiconductor" ], [ "References", "''This article incorporates public domain text from the National Institute of Environmental Health Sciences (NIEHS) as quoted.''" ], [ "External links", "* Nanocarbon: From Graphene to Buckyballs.", "Interactive 3D models of cyclohexane, benzene, graphene, graphite, chiral & non-chiral nanotubes, and C60 Buckyballs - WeCanFigureThisOut.org.", "* C60 and Carbon Nanotubes a short video explaining how nanotubes can be made from modified graphite sheets and the three different types of nanotubes that are formed* Learning module for Bandstructure of Carbon Nanotubes and Nanoribbons* Selection of free-download articles on carbon nanotubes* WOLFRAM Demonstrations Project: Electronic Band Structure of a Single-Walled Carbon Nanotube by the Zone-Folding Method* WOLFRAM Demonstrations Project: Electronic Structure of a Single-Walled Carbon Nanotube in Tight-Binding Wannier Representation" ] ]

[ [ "Czech Republic" ], [ "Introduction", "The '''Czech Republic''', also known as '''Czechia''', is a landlocked country in Central Europe.", "Historically known as '''Bohemia''', it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast.", "The Czech Republic has a hilly landscape that covers an area of with a mostly temperate continental and oceanic climate.", "The capital and largest city is Prague; other major cities and urban areas include Brno, Ostrava, Plzeň and Liberec.The Duchy of Bohemia was founded in the late 9th century under Great Moravia.", "It was formally recognized as an Imperial State of the Holy Roman Empire in 1002 and became a kingdom in 1198.Following the Battle of Mohács in 1526, all of the Crown lands of Bohemia were gradually integrated into the Habsburg monarchy.", "Nearly a hundred years later, the Protestant Bohemian Revolt led to the Thirty Years' War.", "After the Battle of White Mountain, the Habsburgs consolidated their rule.", "With the dissolution of the Holy Roman Empire in 1806, the Crown lands became part of the Austrian Empire.In the 19th century, the Czech lands became more industrialized, and in 1918 most of it became part of the First Czechoslovak Republic following the collapse of Austria-Hungary after World War I. Czechoslovakia was the only country in Central and Eastern Europe to remain a parliamentary democracy during the entirety of the interwar period.", "After the Munich Agreement in 1938, Nazi Germany systematically took control over the Czech lands.", "Czechoslovakia was restored in 1945 and three years later became an Eastern Bloc communist state following a coup d'état in 1948.Attempts to liberalize the government and economy were suppressed by a Soviet-led invasion of the country during the Prague Spring in 1968.In November 1989, the Velvet Revolution ended communist rule in the country and restored democracy.", "On 31 December 1992, Czechoslovakia was peacefully dissolved, with its constituent states becoming the independent states of the Czech Republic and Slovakia.The Czech Republic is a unitary parliamentary republic and developed country with an advanced, high-income social market economy.", "It is a welfare state with a European social model, universal health care and free-tuition university education.", "It ranks 32nd in the Human Development Index.", "The Czech Republic is a member of the United Nations, NATO, the European Union, the OECD, the OSCE, the Council of Europe and the Visegrád Group.==Etymology==The traditional English name \"Bohemia\" derives from Latin: ''Boiohaemum'', which means \"home of the Boii\" (a Gallic tribe).", "The current English name ultimately comes from the Czech word .", "The name comes from the Slavic tribe () and, according to legend, their leader Čech, who brought them to Bohemia, to settle on Říp Mountain.", "The etymology of the word can be traced back to the Proto-Slavic root , meaning \"member of the people; kinsman\", thus making it cognate to the Czech word (a person).The country has been traditionally divided into three lands, namely Bohemia () in the west, Moravia () in the east, and Czech Silesia (; the smaller, south-eastern part of historical Silesia, most of which is located within modern Poland) in the northeast.", "Known as the ''lands of the Bohemian Crown'' since the 14th century, a number of other names for the country have been used, including ''Czech/Bohemian lands'', ''Bohemian Crown'', ''Czechia'', and the ''lands of the Crown of Saint Wenceslaus''.", "When the country regained its independence after the dissolution of the Austro-Hungarian empire in 1918, the new name of ''Czechoslovakia'' was coined to reflect the union of the Czech and Slovak nations within one country.After Czechoslovakia dissolved on the last day of 1992, was adopted as the Czech short name for the new state and the Ministry of Foreign Affairs of the Czech Republic recommended ''Czechia'' for the English-language equivalent.", "This form was not widely adopted at the time, leading to the long name ''Czech Republic'' being used in English in nearly all circumstances.", "The Czech government directed use of ''Czechia'' as the official English short name in 2016.The short name has been listed by the United Nations and is used by other organizations such as the European Union, NATO, the CIA, Google Maps, and the European Broadcasting Union.", "In 2022, the American ''AP Stylebook'' stated in its entry on the country that \"Czechia, the Czech Republic.", "Both are acceptable.", "The shorter name Czechia is preferred by the Czech government.", "If using Czechia, clarify in the story that the country is more widely known in English as the Czech Republic.\"" ], [ "History", "=== Prehistory ===Archaeologists have found evidence of prehistoric human settlements in the area, dating back to the Paleolithic era.In the classical era, as a result of the 3rd century BC Celtic migrations, Bohemia became associated with the Boii.", "The Boii founded an oppidum near the site of modern Prague.", "Later in the 1st century, the Germanic tribes of the Marcomanni and Quadi settled there.Slavs from the Black Sea–Carpathian region settled in the area (their migration was pushed by an invasion of peoples from Siberia and Eastern Europe into their area: Huns, Avars, Bulgars and Magyars).", "In the sixth century, the Huns had moved westwards into Bohemia, Moravia, and some of present-day Austria and Germany.During the 7th century, the Frankish merchant Samo, supporting the Slavs fighting against nearby settled Avars, became the ruler of the first documented Slavic state in Central Europe, Samo's Empire.", "The principality of Great Moravia, controlled by Moymir dynasty, arose in the 8th century.", "It reached its zenith in the 9th (during the reign of Svatopluk I of Moravia), holding off the influence of the Franks.", "Great Moravia was Christianized, with a role being played by the Byzantine mission of Cyril and Methodius.", "They codified the Old Church Slavonic language, the first literary and liturgical language of the Slavs, and the Glagolitic script.=== Bohemia ===Crown of Bohemia within the Holy Roman Empire (1600).", "The Czech lands were part of the Empire in 1002–1806, and Prague was the imperial seat in 1346–1437 and 1583–1611.The Duchy of Bohemia emerged in the late 9th century when it was unified by the Přemyslid dynasty.", "Bohemia was from 1002 until 1806 an Imperial Estate of the Holy Roman Empire.In 1212, Přemysl Ottokar I extracted the Golden Bull of Sicily from the emperor, confirming Ottokar and his descendants' royal status; the Duchy of Bohemia was raised to a Kingdom.", "German immigrants settled in the Bohemian periphery in the 13th century.", "The Mongols in the invasion of Europe carried their raids into Moravia but were defensively defeated at Olomouc.After a series of dynastic wars, the House of Luxembourg gained the Bohemian throne.Efforts for a reform of the church in Bohemia started already in the late 14th century.", "Jan Hus' followers seceded from some practices of the Roman Church and in the Hussite Wars (1419–1434) defeated five crusades organized against them by Sigismund.", "During the next two centuries, 90% of the population in Bohemia and Moravia were considered Hussites.", "The pacifist thinker Petr Chelčický inspired the movement of the Moravian Brethren (by the middle of the 15th century) that completely separated from the Roman Catholic Church.Battle between Hussites and crusaders during the Hussite Wars; Jena Codex, 15th centuryOn 21 December 1421, Jan Žižka, a successful military commander and mercenary, led his group of forces in the Battle of Kutná Hora, resulting in a victory for the Hussites.", "He is honoured to this day as a national hero.After 1526 Bohemia came increasingly under Habsburg control as the Habsburgs became first the elected and then in 1627 the hereditary rulers of Bohemia.", "Between 1583 and 1611 Prague was the official seat of the Holy Roman Emperor Rudolf II and his court.The Defenestration of Prague and subsequent revolt against the Habsburgs in 1618 marked the start of the Thirty Years' War.", "In 1620, the rebellion in Bohemia was crushed at the Battle of White Mountain and the ties between Bohemia and the Habsburgs' hereditary lands in Austria were strengthened.", "The leaders of the Bohemian Revolt were executed in 1621.The nobility and the middle class Protestants had to either convert to Catholicism or leave the country.The following era of 1620 to the late 18th century became known as the \"Dark Age\".", "During the Thirty Years' War, the population of the Czech lands declined by a third through the expulsion of Czech Protestants as well as due to the war, disease and famine.", "The Habsburgs prohibited all Christian confessions other than Catholicism.", "The flowering of Baroque culture shows the ambiguity of this historical period.Ottoman Turks and Tatars invaded Moravia in 1663.In 1679–1680 the Czech lands faced the Great Plague of Vienna and an uprising of serfs.Defenestration of Prague marked the beginning of the Bohemian Revolt against the Habsburgs and therefore the first phase of the Thirty Years' War.There were peasant uprisings influenced by famine.", "Serfdom was abolished between 1781 and 1848.Several battles of the Napoleonic Wars took place on the current territory of the Czech Republic.The end of the Holy Roman Empire in 1806 led to degradation of the political status of Bohemia which lost its position of an electorate of the Holy Roman Empire as well as its own political representation in the Imperial Diet.", "Bohemian lands became part of the Austrian Empire.", "During the 18th and 19th century the Czech National Revival began its rise, with the purpose to revive Czech language, culture, and national identity.", "The Revolution of 1848 in Prague, striving for liberal reforms and autonomy of the Bohemian Crown within the Austrian Empire, was suppressed.It seemed that some concessions would be made also to Bohemia, but in the end, the Emperor Franz Joseph I affected a compromise with Hungary only.", "The Austro-Hungarian Compromise of 1867 and the never realized coronation of Franz Joseph as King of Bohemia led to a disappointment of some Czech politicians.", "The Bohemian Crown lands became part of the so-called Cisleithania.The Czech Social Democratic and progressive politicians started the fight for universal suffrage.", "The first elections under universal male suffrage were held in 1907.=== Czechoslovakia ===The alt=In 1918, during the collapse of the Habsburg monarchy at the end of World War I, the independent republic of Czechoslovakia, which joined the winning Allied powers, was created, with Tomáš Garrigue Masaryk in the lead.", "This new country incorporated the Bohemian Crown.The First Czechoslovak Republic comprised only 27% of the population of the former Austria-Hungary, but nearly 80% of the industry, which enabled it to compete with Western industrial states.", "In 1929 compared to 1913, the gross domestic product increased by 52% and industrial production by 41%.", "In 1938 Czechoslovakia held 10th place in the world industrial production.", "Czechoslovakia was the only country in Central and Eastern Europe to remain a liberal democracy throughout the entire interwar period.", "Although the First Czechoslovak Republic was a unitary state, it provided certain rights to its minorities, the largest being Germans (23.6% in 1921), Hungarians (5.6%) and Ukrainians (3.5%).Prague during the 1968 Warsaw Pact invasion of CzechoslovakiaWestern Czechoslovakia was occupied by Nazi Germany, which placed most of the region into the Protectorate of Bohemia and Moravia.", "The Protectorate was proclaimed part of the Third Reich, and the president and prime minister were subordinated to Nazi Germany's ''Reichsprotektor''.", "One Nazi concentration camp was located within the Czech territory at Terezín, north of Prague.", "The vast majority of the Protectorate's Jews were murdered in Nazi-run concentration camps.", "The Nazi called for the extermination, expulsion, Germanization or enslavement of most or all Czechs for the purpose of providing more living space for the German people.", "There was Czechoslovak resistance to Nazi occupation as well as reprisals against the Czechoslovaks for their anti-Nazi resistance.", "The German occupation ended on 9 May 1945, with the arrival of the Soviet and American armies and the Prague uprising.", "Most of Czechoslovakia's German-speakers were forcibly expelled from the country, first as a result of local acts of violence and then under the aegis of an \"organized transfer\" confirmed by the Soviet Union, the United States, and Great Britain at the Potsdam Conference.In the 1946 elections, the Communist Party gained 38% of the votes and became the largest party in the Czechoslovak parliament, formed a coalition with other parties, and consolidated power.", "A coup d'état came in 1948 and a single-party government was formed.", "For the next 41 years, the Czechoslovak Communist state conformed to Eastern Bloc economic and political features.", "The Prague Spring political liberalization was stopped by the 1968 Warsaw Pact invasion of Czechoslovakia.", "Analysts believe that the invasion caused the communist movement to fracture, ultimately leading to the Revolutions of 1989.=== Czech Republic ===Václav Havel, one of the most important figures in Czech history during the 20th century.", "Leader of the Velvet Revolution, the last president of Czechoslovakia and the first president of the Czech Republic.In November 1989, Czechoslovakia again became a liberal democracy through the Velvet Revolution.", "However, Slovak national aspirations strengthened (Hyphen War) and on 31 December 1992, the country peacefully split into the independent countries of the Czech Republic and Slovakia.", "Both countries went through economic reforms and privatizations, with the intention of creating a market economy, as they have been trying to do since 1990, when Czechs and Slovaks still shared the common state.", "This process was largely successful; in 2006 the Czech Republic was recognized by the World Bank as a \"developed country\", and in 2009 the Human Development Index ranked it as a nation of \"Very High Human Development\".From 1991, the Czech Republic, originally as part of Czechoslovakia and since 1993 in its own right, has been a member of the Visegrád Group and from 1995, the OECD.", "The Czech Republic joined NATO on 12 March 1999 and the European Union on 1 May 2004.On 21 December 2007 the Czech Republic joined the Schengen Area.Until 2017, either the centre-left Czech Social Democratic Party or the centre-right Civic Democratic Party led the governments of the Czech Republic.", "In October 2017, the populist movement ANO 2011, led by the country's second-richest man, Andrej Babiš, won the elections with three times more votes than its closest rival, the Civic Democrats.", "In December 2017, Czech president Miloš Zeman appointed Andrej Babiš as the new prime minister.In the 2021 elections, ANO 2011 was narrowly defeated and Petr Fiala became the new prime minister.", "He formed a government coalition of the alliance SPOLU (Civic Democratic Party, KDU-ČSL and TOP 09) and the alliance of Pirates and Mayors.", "In January 2023, retired general Petr Pavel won the presidential election, becoming new Czech president to succeed Miloš Zeman.", "Following the 2022 Russian invasion of Ukraine, the country took in half a million Ukrainian refugees, the largest number per capita in the world." ], [ "Geography", "Topographic mapThe Czech Republic lies mostly between latitudes 48° and 51° N and longitudes 12° and 19° E.Bohemia, to the west, consists of a basin drained by the Elbe () and the Vltava rivers, surrounded by mostly low mountains, such as the Krkonoše range of the Sudetes.", "The highest point in the country, Sněžka at , is located here.", "Moravia, the eastern part of the country, is also hilly.", "It is drained mainly by the Morava River, but it also contains the source of the Oder River ().Water from the Czech Republic flows to three different seas: the North Sea, Baltic Sea, and Black Sea.", "The Czech Republic also leases the Moldauhafen, a lot in the middle of the Hamburg Docks, which was awarded to Czechoslovakia by Article 363 of the Treaty of Versailles, to allow the landlocked country a place where goods transported down river could be transferred to seagoing ships.", "The territory reverts to Germany in 2028.Phytogeographically, the Czech Republic belongs to the Central European province of the Circumboreal Region, within the Boreal Kingdom.", "According to the World Wide Fund for Nature, the territory of the Czech Republic can be subdivided into four ecoregions: the Western European broadleaf forests, Central European mixed forests, Pannonian mixed forests, and Carpathian montane conifer forests.There are four national parks in the Czech Republic.", "The oldest is Krkonoše National Park (Biosphere Reserve), and the others are Šumava National Park (Biosphere Reserve), Podyjí National Park, and Bohemian Switzerland.The three historical lands of the Czech Republic (formerly some countries of the Bohemian Crown) correspond with the river basins of the Elbe and the Vltava basin for Bohemia, the Morava one for Moravia, and the Oder river basin for Czech Silesia (in terms of the Czech territory).=== Climate ===Köppen climate classification types of the Czech Republic using the 0 °C isothermKöppen climate classification types of the Czech Republic using the −3 °C isothermThe Czech Republic has a temperate climate, situated in the transition zone between the oceanic and continental climate types, with warm summers and cold, cloudy and snowy winters.", "The temperature difference between summer and winter is due to the landlocked geographical position.Temperatures vary depending on the elevation.", "In general, at higher altitudes, the temperatures decrease and precipitation increases.", "The wettest area in the Czech Republic is found around Bílý Potok in Jizera Mountains and the driest region is the Louny District to the northwest of Prague.", "Another factor is the distribution of the mountains.At the highest peak of Sněžka (), the average temperature is , whereas in the lowlands of the South Moravian Region, the average temperature is as high as .", "The country's capital, Prague, has a similar average temperature, although this is influenced by urban factors.The coldest month is usually January, followed by February and December.", "During these months, there is snow in the mountains and sometimes in the cities and lowlands.", "During March, April, and May, the temperature usually increases, especially during April, when the temperature and weather tends to vary during the day.", "Spring is also characterized by higher water levels in the rivers, due to melting snow with occasional flooding.The warmest month of the year is July, followed by August and June.", "On average, summer temperatures are about higher than during winter.", "Summer is also characterized by rain and storms.Autumn generally begins in September, which is still warm and dry.", "During October, temperatures usually fall below or and deciduous trees begin to shed their leaves.", "By the end of November, temperatures usually range around the freezing point.The coldest temperature ever measured was in Litvínovice near České Budějovice in 1929, at and the hottest measured, was at in Dobřichovice in 2012.Most rain falls during the summer.", "Sporadic rainfall is throughout the year (in Prague, the average number of days per month experiencing at least of rain varies from 12 in September and October to 16 in November) but concentrated rainfall (days with more than per day) are more frequent in the months of May to August (average around two such days per month).", "Severe thunderstorms, producing damaging straight-line winds, hail, and occasional tornadoes occur, especially during the summer period.=== Environment ===As of 2020, the Czech Republic ranks as the 21st most environmentally conscious country in the world in Environmental Performance Index.", "It had a 2018 Forest Landscape Integrity Index mean score of 1.71/10, ranking it 160th globally out of 172 countries.", "The Czech Republic has four National Parks (Šumava National Park, Krkonoše National Park, České Švýcarsko National Park, Podyjí National Park) and 25 Protected Landscape Areas." ], [ "Government", "The Czech Republic is a pluralist multi-party parliamentary representative democracy.", "The Parliament (''Parlament České republiky'') is bicameral, with the Chamber of Deputies (, 200 members) and the Senate (, 81 members).", "The members of the Chamber of Deputies are elected for a four-year term by proportional representation, with a 5% election threshold.", "There are 14 voting districts, identical to the country's administrative regions.", "The Chamber of Deputies, the successor to the Czech National Council, has the powers and responsibilities of the now defunct federal parliament of the former Czechoslovakia.", "The members of the Senate are elected in single-seat constituencies by two-round runoff voting for a six-year term, with one-third elected every even year in the autumn.", "This arrangement is modeled on the U.S. Senate, but each constituency is roughly the same size and the voting system used is a two-round runoff.Chamber of Deputies, lower house of the Parliament of the Czech RepublicThe president is a formal head of state with limited and specific powers, who appoints the prime minister, as well the other members of the cabinet on a proposal by the prime minister.", "From 1993 until 2012, the President of the Czech Republic was selected by a joint session of the parliament for a five-year term, with no more than two consecutive terms (2x Václav Havel, 2x Václav Klaus).", "Since 2013, the president has been elected directly.", "Some commentators have argued that, with the introduction of direct election of the President, the Czech Republic has moved away from the parliamentary system and towards a semi-presidential one.", "The Government's exercise of executive power derives from the Constitution.", "The members of the government are the Prime Minister, Deputy prime ministers and other ministers.", "The Government is responsible to the Chamber of Deputies.", "The Prime Minister is the head of government and wields powers such as the right to set the agenda for most foreign and domestic policy and choose government ministers.PresidentPetr PavelIndependent9 March 2023President of the SenateMiloš VystrčilODS19 February 2020President of the Chamber of DeputiesMarkéta Pekarová AdamováTOP 0910 November 2021Prime MinisterPetr FialaODS28 November 2021=== Law ===Interior of the Constitutional Court of the Czech Republic in BrnoThe Czech Republic is a unitary state, with a civil law system based on the continental type, rooted in Germanic legal culture.", "The basis of the legal system is the Constitution of the Czech Republic adopted in 1993.The Penal Code is effective from 2010.A new Civil code became effective in 2014.The court system includes district, county, and supreme courts and is divided into civil, criminal, and administrative branches.", "The Czech judiciary has a triumvirate of supreme courts.", "The Constitutional Court consists of 15 constitutional judges and oversees violations of the Constitution by either the legislature or by the government.", "The Supreme Court is formed of 67 judges and is the court of highest appeal for most legal cases heard in the Czech Republic.", "The Supreme Administrative Court decides on issues of procedural and administrative propriety.", "It also has jurisdiction over certain political matters, such as the formation and closure of political parties, jurisdictional boundaries between government entities, and the eligibility of persons to stand for public office.", "The Supreme Court and the Supreme Administrative Court are both based in Brno, as is the Supreme Public Prosecutor's Office.=== Foreign relations ===Visa-free entry countries for Czech citizens in green, EU in blue (see citizenship of the European Union)The Czech Republic has ranked as one of the safest or most peaceful countries for the past few decades.", "It is a member of the United Nations, the European Union, NATO, OECD, Council of Europe and is an observer to the Organization of American States.", "The embassies of most countries with diplomatic relations with the Czech Republic are located in Prague, while consulates are located across the country.The Czech passport is restricted by visas.", "According to the 2018 Henley & Partners Visa Restrictions Index, Czech citizens have visa-free access to 173 countries, which ranks them 7th along with Malta and New Zealand.", "The World Tourism Organization ranks the Czech passport 24th.", "The US Visa Waiver Program applies to Czech nationals.Ministry of Foreign Affairs in PragueThe Prime Minister and Minister of Foreign Affairs have primary roles in setting foreign policy, although the President also has influence and represents the country abroad.", "Membership in the European Union and NATO is central to the Czech Republic's foreign policy.", "The Office for Foreign Relations and Information (ÚZSI) serves as the foreign intelligence agency responsible for espionage and foreign policy briefings, as well as protection of Czech Republic's embassies abroad.The Czech Republic has ties with Slovakia, Poland and Hungary as a member of the Visegrád Group, as well as with Germany, Israel, the United States and the European Union and its members.", "After 2020, relations with Asian democratic states, such as Taiwan, are being strengthened.", "Conversely, the Czech Republic has long had bad relations with Russia, and from 2021 the Czech Republic appears on Russia's official list of enemy countries.", "The Czech Republic also has problematic relations with China.Czech officials have supported dissenters in Belarus, Moldova, Myanmar and Cuba.Famous Czech diplomats of the past included Jaroslav Lev of Rožmitál, Humprecht Jan Czernin, Count Philip Kinsky of Wchinitz and Tettau, Wenzel Anton, Prince of Kaunitz-Rietberg, Prince Karl Philipp Schwarzenberg, Alois Lexa von Aehrenthal, Ottokar Czernin, Edvard Beneš, Jan Masaryk, Jiří Hájek, Jiří Dienstbier, Michael Žantovský, Petr Kolář, Alexandr Vondra, Prince Karel Schwarzenberg and Petr Pavel.=== Military ===General Staff of the Army of the Czech Republic in PragueThe Czech armed forces consist of the Czech Land Forces, the Czech Air Force and of specialized support units.", "The armed forces are managed by the Ministry of Defence.", "The President of the Czech Republic is Commander-in-chief of the armed forces.", "In 2004 the army transformed itself into a fully professional organization and compulsory military service was abolished.", "The country has been a member of NATO since 12 March 1999.Defence spending is approximately 1.28% of the GDP (2021).", "The armed forces are charged with protecting the Czech Republic and its allies, promoting global security interests, and contributing to NATO.Currently, as a member of NATO, the Czech military are participating in the Resolute Support and KFOR operations and have soldiers in Afghanistan, Mali, Bosnia and Herzegovina, Kosovo, Egypt, Israel and Somalia.", "The Czech Air Force also served in the Baltic states and Iceland.", "The main equipment of the Czech military includes JAS 39 Gripen multi-role fighters, Aero L-159 Alca combat aircraft, Mi-35 attack helicopters, armored vehicles (Pandur II, OT-64, OT-90, BVP-2) and tanks (T-72 and T-72M4CZ).The most famous Czech, and therefore Czechoslovak, soldiers and military leaders of the past were Ottokar II of Bohemia, John of Bohemia, Jan Žižka, Albrecht von Wallenstein, Karl Philipp, Prince of Schwarzenberg, Joseph Radetzky von Radetz, Josef Šnejdárek, Heliodor Píka, Ludvík Svoboda, Jan Kubiš, Jozef Gabčík, František Fajtl and Petr Pavel.=== Human rights ===Human rights in the Czech Republic are guaranteed by the Charter of Fundamental Rights and Freedoms and international treaties on human rights.", "Nevertheless, there were cases of human rights violations such as discrimination against Roma children, for which the European Commission asked the Czech Republic to provide an explanation, or the illegal sterilization of Roma women, for which the government apologized.Logo of the Czech humanitarian organization People in NeedPrague is the seat of Radio Free Europe/Radio Liberty.", "Today, the station is based in Hagibor.", "At the beginning of the 1990s, Václav Havel personally invited her to Czechoslovakia.People of the same sex can enter into a \"registered partnership\" in the Czech Republic.", "Conducting same-sex marriage is not legal under current Czech law.The best-known Czech activists and supporters of human rights include Berta von Suttner, born in Prague, who won the Nobel Peace Prize for her pacifist struggle, philosopher and the first Czechoslovak president Tomáš Garrigue Masaryk, student Jan Palach, who set himself on fire in 1969 in protest against the Soviet occupation, Karel Schwarzenberg, who was chairman of the International Helsinki Committee for Human Rights between 1984 and 1990, Václav Havel, long-time dissident and later president, sociologist and dissident Jiřina Šiklová and Šimon Pánek, founder and director of the People in Need organization.=== Administrative divisions ===Since 2000, the Czech Republic has been divided into thirteen regions (Czech: ''kraje'', singular ''kraj'') and the capital city of Prague.", "Every region has its own elected regional assembly and a regional governor.", "In Prague, the assembly and presidential powers are executed by the city council and the mayor.The older seventy-six districts (''okresy'', singular ''okres'') including three \"statutory cities\" (without Prague, which had special status) lost most of their importance in 1999 in an administrative reform; they remain as territorial divisions and seats of various branches of state administration.The smallest administrative units are ''obce'' (municipalities).", "As of 2021, the Czech Republic is divided into 6,254 municipalities.", "Cities and towns are also municipalities.", "The capital city of Prague is a region and municipality at the same time." ], [ "Economy", "Real GDP per capita in the Czech Republic from 1973 to 2018The Czech Republic is part of the European Single Market and the Schengen Area (dark and light blue on the map above), but uses its own currency, the Czech koruna.The Czech Republic has a developed, high-income export-oriented social market economy based in services, manufacturing and innovation, that maintains a welfare state and the European social model.", "The Czech Republic participates in the European Single Market as a member of the European Union and is therefore a part of the economy of the European Union, but uses its own currency, the Czech koruna, instead of the euro.", "It has a per capita GDP rate that is 91% of the EU average and is a member of the OECD.", "Monetary policy is conducted by the Czech National Bank, whose independence is guaranteed by the Constitution.", "The Czech Republic ranks 12th in the UN inequality-adjusted human development and 24th in World Bank Human Capital Index.", "It was described by ''The Guardian'' as \"one of Europe's most flourishing economies\"., the country's GDP per capita at purchasing power parity is $51,329 and $29,856 at nominal value.", "According to Allianz A.G., in 2018 the country was an MWC (mean wealth country), ranking 26th in net financial assets.", "The country experienced a 4.5% GDP growth in 2017.The 2016 unemployment rate was the lowest in the EU at 2.4%, and the 2016 poverty rate was the second lowest of OECD members.", "Czech Republic ranks 27th in the 2021 Index of Economic Freedom, 31st in the 2023 Global Innovation Index, down from 24th in the 2016, 29th in the Global Competitiveness Report, and 25th in the Global Enabling Trade Report.The Czech Republic has a diverse economy that ranks 7th in the 2016 Economic Complexity Index.", "The industrial sector accounts for 37.5% of the economy, while services account for 60% and agriculture for 2.5%.", "The largest trading partner for both export and import is Germany and the EU in general.", "Dividends worth CZK 270 billion were paid to the foreign owners of Czech companies in 2017, which has become a political issue.", "The country has been a member of the Schengen Area since 1 May 2004, having abolished border controls, completely opening its borders with all of its neighbors on 21 December 2007.=== Industry ===Škoda Octavia RS iV the largest companies by revenue in the Czech Republic were: automobile manufacturer Škoda Auto, utility company ČEZ Group, conglomerate Agrofert, energy trading company EPH, oil processing company Unipetrol, electronics manufacturer Foxconn CZ and steel producer Moravia Steel.", "Other Czech transportation companies include: Škoda Transportation (tramways, trolleybuses, metro), Tatra (heavy trucks, the second oldest car maker in the world), Avia (medium trucks), Karosa and SOR Libchavy (buses), Aero Vodochody (military aircraft), Let Kunovice (civil aircraft), Zetor (tractors), Jawa Moto (motorcycles) and Čezeta (electric scooters).Škoda Transportation is the fourth largest tram producer in the world; nearly one third of all trams in the world come from Czech factories.", "The Czech Republic is also the world's largest vinyl records manufacturer, with GZ Media producing about 6 million pieces annually in Loděnice.", "Česká zbrojovka is among the ten largest firearms producers in the world and five who produce automatic weapons.In the food industry, Czech companies include Agrofert, Kofola and Hamé.=== Energy ===Dukovany Nuclear Power StationProduction of Czech electricity exceeds consumption by about 10 TWh per year, the excess being exported.", "Nuclear power presently provides about 30 percent of the total power needs, its share is projected to increase to 40 percent.", "In 2005, 65.4 percent of electricity was produced by steam and combustion power plants (mostly coal); 30 percent by nuclear plants; and 4.6 percent came from renewable sources, including hydropower.", "The largest Czech power resource is Temelín Nuclear Power Station, with another nuclear power plant in Dukovany.The Czech Republic is reducing its dependence on highly polluting low-grade brown coal as a source of energy.", "Natural gas is purchased from Norwegian companies and as liquefied gas LNG from the Netherlands and Belgium.", "In the past, three-quarters of gas supplies came from Russia, but after the outbreak of the war in Ukraine, the government gradually stopped these supplies.", "Gas consumption (approx.", "100 TWh in 2003–2005) is almost double electricity consumption.", "South Moravia has small oil and gas deposits.=== Transportation infrastructure ===Václav Havel Airport Prague the road network in the Czech Republic is long, out of which are motorways.", "The speed limit is within towns, outside of towns and on motorways.The Czech Republic has one of the densest rail networks in the world.", "the country has of lines.", "Of that number, is electrified, are single-line tracks and are double and multiple-line tracks.", "The length of tracks is , out of which is electrified.České dráhy (the Czech Railways) is the main railway operator in the country, with about 180 million passengers carried yearly.", "Maximum speed is limited to .Václav Havel Airport in Prague is the main international airport in the country.", "In 2019, it handled 17.8 million passengers.", "In total, the Czech Republic has 91 airports, six of which provide international air services.", "The public international airports are in Brno, Karlovy Vary, Mnichovo Hradiště, Mošnov (near Ostrava), Pardubice and Prague.", "The non-public international airports capable of handling airliners are in Kunovice and Vodochody.Russia, via pipelines through Ukraine and to a lesser extent, Norway, via pipelines through Germany, supply the Czech Republic with liquid and natural gas.=== Communications and IT ===Founders and owners of the antivirus group AvastThe Czech Republic ranks in the top 10 countries worldwide with the fastest average internet speed.", "By the beginning of 2008, there were over 800 mostly local WISPs, with about 350,000 subscribers in 2007.Plans based on either GPRS, EDGE, UMTS or CDMA2000 are being offered by all three mobile phone operators (T-Mobile, O2, Vodafone) and internet provider U:fon.", "Government-owned Český Telecom slowed down broadband penetration.", "At the beginning of 2004, local-loop unbundling began and alternative operators started to offer ADSL and also SDSL.", "This and later privatization of Český Telecom helped drive down prices.On 1 July 2006, Český Telecom was acquired by globalized company (Spain-owned) Telefónica group and adopted the new name Telefónica O2 Czech Republic.", ", VDSL and ADSL2+ are offered in variants, with download speeds of up to 50 Mbit/s and upload speeds of up to 5 Mbit/s.", "Cable internet is gaining more popularity with its higher download speeds ranging from 50 Mbit/s to 1 Gbit/s.Two computer security companies, Avast and AVG, were founded in the Czech Republic.", "In 2016, Avast led by Pavel Baudiš bought rival AVG for US$1.3 billion, together at the time, these companies had a user base of about 400 million people and 40% of the consumer market outside of China.", "Avast is the leading provider of antivirus software, with a 20.5% market share.=== Tourism ===Medieval castle KarlštejnPrague is the fifth most visited city in Europe after London, Paris, Istanbul and Rome.", "In 2001, the total earnings from tourism reached 118 billion CZK, making up 5.5% of GNP and 9% of overall export earnings.", "The industry employs more than 110,000 people – over 1% of the population.Guidebooks and tourists reporting overcharging by taxi drivers and pickpocketing problems are mainly in Prague, though the situation has improved recently.", "Since 2005, Prague's mayor, Pavel Bém, has worked to improve this reputation by cracking down on petty crime and, aside from these problems, Prague is a \"safe\" city.", "The Czech Republic's crime rate is described by the United States State department as \"low\".One of the tourist attractions in the Czech Republic is the Nether district Vítkovice in Ostrava.The Czech Republic boasts 16 UNESCO World Heritage Sites, 3 of them are transnational.", ", further 14 sites are on the tentative list.Český KrumlovArchitectural heritage is an object of interest to visitors – it includes castles and châteaux from different historical epoques, namely Karlštejn Castle, Český Krumlov and the Lednice–Valtice Cultural Landscape.", "There are 12 cathedrals and 15 churches elevated to the rank of basilica by the Pope, calm monasteries.Away from the towns, areas such as Bohemian Paradise, Bohemian Forest and the Giant Mountains attract visitors seeking outdoor pursuits.", "There is a number of beer festivals.The country is also known for its various museums.", "Puppetry and marionette exhibitions are with a number of puppet festivals throughout the country.", "Aquapalace Prague in Čestlice is the largest water park in the country.=== Science ===Chemist Jaroslav Heyrovský, Nobel Prize winnerThe Czech lands have a long and well-documented history of scientific innovation.", "Today, the Czech Republic has a highly sophisticated, developed, high-performing, innovation-oriented scientific community supported by the government, industry, and leading universities.", "Czech scientists are embedded members of the global scientific community.", "They contribute annually to multiple international academic journals and collaborate with their colleagues across boundaries and fields.", "The Czech Republic was ranked 24th in the Global Innovation Index in 2020 and 2021, up from 26th in 2019.Historically, the Czech lands, especially Prague, have been the seat of scientific discovery going back to early modern times, including Tycho Brahe, Nicolaus Copernicus, and Johannes Kepler.", "In 1784 the scientific community was first formally organized under the charter of the Royal Czech Society of Sciences.", "Currently, this organization is known as the Czech Academy of Sciences.", "Similarly, the Czech lands have a well-established history of scientists, including Nobel laureates biochemists Gerty and Carl Ferdinand Cori, chemists Jaroslav Heyrovský and Otto Wichterle, physicists Ernst Mach and Peter Grünberg, physiologist Jan Evangelista Purkyně and chemist Antonín Holý.", "Sigmund Freud, the founder of psychoanalysis, was born in Příbor, Gregor Mendel, the founder of genetics, was born in Hynčice and spent most of his life in Brno, logician and mathematician Kurt Gödel was born in Brno.Eli Beamlines Science Center with the most powerful laser in the world in Dolní BřežanyHistorically, most scientific research was recorded in Latin, but from the 18th century onwards increasingly in German and later in Czech, archived in libraries supported and managed by religious groups and other denominations as evidenced by historical locations of international renown and heritage such as the Strahov Monastery and the Clementinum in Prague.", "Increasingly, Czech scientists publish their work and that of their history in English.The current important scientific institution is the already mentioned Academy of Sciences of the Czech Republic, the CEITEC Institute in Brno or the HiLASE and Eli Beamlines centers with the most powerful laser in the world in Dolní Břežany.", "Prague is the seat of the administrative center of the GSA Agency operating the European navigation system Galileo and the European Union Agency for the Space Programme." ], [ "Demographics", "The total fertility rate (TFR) in 2020 was estimated at 1.71 children per woman, which is below the replacement rate of 2.1.The Czech Republic's population has an average age of 43.3 years.", "The life expectancy in 2021 was estimated to be 79.5 years (76.55 years male, 82.61 years female).", "About 77,000 people immigrate to the Czech Republic annually.", "Vietnamese immigrants began settling in the country during the Communist period, when they were invited as guest workers by the Czechoslovak government.", "In 2009, there were about 70,000 Vietnamese in the Czech Republic.", "Most decide to stay in the country permanently.According to results of the 2021 census, the majority of the inhabitants of the Czech Republic are Czechs (57.3%), followed by Moravians (3.4%), Slovaks (0.9%), Ukrainians (0.7%), Viets (0.3%), Poles (0.3%), Russians (0.2%), Silesians (0.1%) and Germans (0.1%).", "Another 4.0% declared combination of two nationalities (3.6% combination of Czech and other nationality).", "As the 'nationality' was an optional item, a number of people left this field blank (31.6%).", "According to some estimates, there are about 250,000 Romani people in the Czech Republic.", "The Polish minority resides mainly in the Trans-Olza region.There were 658,564 foreigners residing in the country in 2021, according to the Czech Statistical Office, with the largest groups being Ukrainian (22%), Slovak (22%), Vietnamese (12%), Russian (7%) and German (4%).", "Most of the foreign population lives in Prague (37.3%) and Central Bohemia Region (13.2%).The Jewish population of Bohemia and Moravia, 118,000 according to the 1930 census, was nearly annihilated by the Nazi Germans during the Holocaust.", "There were approximately 3,900 Jews in the Czech Republic in 2021.The former Czech prime minister, Jan Fischer, is of Jewish faith.Nationality of residents, who answered the question in the Census 2021:+NationalityShareCzech83.76%Moravian4.99%Czech and Moravian2.50%Slovak1.33%Ukrainian1.08%Czech and Slovak0.82%Vietnamese0.44%Polish0.37%Russian0.35%''Other''4.36%=== Largest cities ====== Religion ===About 75% to 79% of residents of the Czech Republic do not declare having any religion or faith in surveys, and the proportion of convinced atheists (30%) is the third highest in the world behind those of China (47%) and Japan (31%).", "The Czech people have been historically characterized as \"tolerant and even indifferent towards religion\".", "The religious identity of the country has changed drastically since the first half of the 20th century, when more than 90% of Czechs were Christians.Saint Wenceslaus, patron saint of the Czech landsChristianization in the 9th and 10th centuries introduced Catholicism.", "After the Bohemian Reformation, most Czechs became followers of Jan Hus, Petr Chelčický and other regional Protestant Reformers.", "Taborites and Utraquists were Hussite groups.", "Towards the end of the Hussite Wars, the Utraquists changed sides and allied with the Catholic Church.", "Following the joint Utraquist—Catholic victory, Utraquism was accepted as a distinct form of Christianity to be practiced in Bohemia by the Catholic Church while all remaining Hussite groups were prohibited.", "After the Reformation, some Bohemians went with the teachings of Martin Luther, especially Sudeten Germans.", "In the wake of the Reformation, Utraquist Hussites took a renewed increasingly anti-Catholic stance, while some of the defeated Hussite factions were revived.", "After the Habsburgs regained control of Bohemia, the whole population was forcibly converted to Catholicism—even the Utraquist Hussites.", "Going forward, Czechs have become more wary and pessimistic of religion as such.", "A history of resistance to the Catholic Church followed.", "It suffered a schism with the neo-Hussite Czechoslovak Hussite Church in 1920, lost the bulk of its adherents during the Communist era and continues to lose in the modern, ongoing secularization.", "Protestantism never recovered after the Counter-Reformation was introduced by the Austrian Habsburgs in 1620.Prior to the Holocaust, the Czech Republic had a sizable Jewish community of around 100,000.There are many historically important and culturally relevant Synagogues in the Czech Republic such as Europe's oldest active Synagogue, The Old New Synagogue and the second largest Synagogue in Europe, the Great Synagogue (Plzeň).", "The Holocaust decimated Czech Jewry and the Jewish population as of 2021 is 3,900.According to the 2011 census, 34% of the population stated they had no religion, 10.3% was Catholic, 0.8% was Protestant (0.5% Czech Brethren and 0.4% Hussite), and 9% followed other forms of religion both denominational or not (of which 863 people answered they are Pagan).", "45% of the population did not answer the question about religion.", "From 1991 to 2001 and further to 2011 the adherence to Catholicism decreased from 39% to 27% and then to 10%; Protestantism similarly declined from 3.7% to 2% and then to 0.8%.", "The Muslim population is estimated to be 20,000 representing 0.2% of the population.The proportion of religious believers varies significantly across the country, from 55% in Zlín Region to 16% in Ústí nad Labem Region.=== Education and health care ===The oldest part of Charles University, founded in 1348Education in the Czech Republic is compulsory for nine years and citizens have access to a free-tuition university education, while the average number of years of education is 13.1.Additionally, the Czech Republic has a \"relatively equal\" educational system in comparison with other countries in Europe.", "Founded in 1348, Charles University was the first university in Central Europe.", "Other major universities in the country are Masaryk University, Czech Technical University, Palacký University, Academy of Performing Arts and University of Economics.The Programme for International Student Assessment, coordinated by the OECD, currently ranks the Czech education system as the 15th most successful in the world, higher than the OECD average.", "The UN Education Index ranks the Czech Republic 10th (positioned behind Denmark and ahead of South Korea).Health care in the Czech Republic is similar in quality to that of other developed nations.", "The Czech universal health care system is based on a compulsory insurance model, with fee-for-service care funded by mandatory employment-related insurance plans.", "According to the 2016 Euro health consumer index, a comparison of healthcare in Europe, the Czech healthcare is 13th, ranked behind Sweden and two positions ahead of the United Kingdom." ], [ "Culture", "=== Art ===Venus of Dolní Věstonice is the treasure of prehistoric art.", "Theodoric of Prague was a painter in the Gothic era who decorated the castle Karlstejn.", "In the Baroque era, there were Wenceslaus Hollar, Jan Kupecký, Karel Škréta, Anton Raphael Mengs or Petr Brandl, sculptors Matthias Braun and Ferdinand Brokoff.", "In the first half of the 19th century, Josef Mánes joined the romantic movement.", "In the second half of the 19th century had the main say the so-called \"National Theatre generation\": sculptor Josef Václav Myslbek and painters Mikoláš Aleš, Václav Brožík, Vojtěch Hynais or Julius Mařák.", "At the end of the century came a wave of Art Nouveau.", "Alfons Mucha became the main representative.", "He is known for Art Nouveau posters and his cycle of 20 large canvases named the Slav Epic, which depicts the history of Czechs and other Slavs., the Slav Epic can be seen in the Veletržní Palace of the National Gallery in Prague, which manages the largest collection of art in the Czech Republic.", "Max Švabinský was another Art nouveau painter.", "The 20th century brought an avant-garde revolution.", "In the Czech lands mainly expressionist and cubist: Josef Čapek, Emil Filla, Bohumil Kubišta, Jan Zrzavý.", "Surrealism emerged particularly in the work of Toyen, Josef Šíma and Karel Teige.", "In the world, however, he pushed mainly František Kupka, a pioneer of abstract painting.", "As illustrators and cartoonists in the first half of the 20th century gained fame Josef Lada, Zdeněk Burian or Emil Orlík.", "Art photography has become a new field (František Drtikol, Josef Sudek, later Jan Saudek or Josef Koudelka).The Czech Republic is known for its individually made, mouth-blown, and decorated Bohemian glass.=== Architecture ===Historic center of PragueThe earliest preserved stone buildings in Bohemia and Moravia date back to the time of the Christianization in the 9th and 10th centuries.", "Since the Middle Ages, the Czech lands have been using the same architectural styles as most of Western and Central Europe.", "The oldest still standing churches were built in the Romanesque style.", "During the 13th century, it was replaced by the Gothic style.", "In the 14th century, Emperor Charles IV invited architects from France and Germany, Matthias of Arras and Peter Parler, to his court in Prague.", "During the Middle Ages, some fortified castles were built by the king and aristocracy, as well as some monasteries.The Renaissance style penetrated the Bohemian Crown in the late 15th century when the older Gothic style started to be mixed with Renaissance elements.", "An example of pure Renaissance architecture in Bohemia is the Queen Anne's Summer Palace, which was situated in the garden of Prague Castle.", "Evidence of the general reception of the Renaissance in Bohemia, involving an influx of Italian architects, can be found in spacious chateaus with arcade courtyards and geometrically arranged gardens.", "Emphasis was placed on comfort, and buildings that were built for entertainment purposes also appeared.In the 17th century, the Baroque style spread throughout the Crown of Bohemia.In the 18th century, Bohemia produced an architectural peculiarity – the ''Baroque Gothic style'', a synthesis of the Gothic and Baroque styles.distinct cubist style in architecture and applied arts.", "It later evolved into national Czechoslovak style, ''rondocubism''.During the 19th century stands the revival architectural styles.", "Some churches were restored to their presumed medieval appearance and there were constructed buildings in the Neo-Romanesque, Neo-Gothic and Neo-Renaissance styles.", "At the turn of the 19th and 20th centuries, the new art style appeared in the Czech lands – Art Nouveau.Bohemia contributed an unusual style to the world's architectural heritage when Czech architects attempted to transpose the Cubism of painting and sculpture into architecture.Between World Wars I and II, Functionalism, with its sober, progressive forms, took over as the main architectural style.After World War II and the Communist coup in 1948, art in Czechoslovakia became Soviet-influenced.", "The Czechoslovak avant-garde artistic movement is known as the ''Brussels style came up'' in the time of political liberalization of Czechoslovakia in the 1960s.", "Brutalism dominated in the 1970s and 1980s.The Czech Republic is not shying away from the more modern trends of international architecture, an example is the Dancing House (Tančící dům) in Prague, Golden Angel in Prague or Congress Centre in Zlín.Influential Czech architects include Peter Parler, Benedikt Rejt, Jan Santini Aichel, Kilian Ignaz Dientzenhofer, Josef Fanta, Josef Hlávka, Josef Gočár, Pavel Janák, Jan Kotěra, Věra Machoninová, Karel Prager, Karel Hubáček, Jan Kaplický, Eva Jiřičná or Josef Pleskot.=== Literature ===Franz KafkaThe literature from the area of today's Czech Republic was mostly written in Czech, but also in Latin and German or even Old Church Slavonic.", "Franz Kafka, although a competent user of Czech, wrote in his mother tongue, German.", "His works include ''The Trial'' and ''The Castle''.In the second half of the 13th century, the royal court in Prague became one of the centers of German Minnesang and courtly literature.", "The Czech German-language literature can be seen in the first half of the 20th century.Bible translations played a role in the development of Czech literature.", "The oldest Czech translation of the Psalms originated in the late 13th century and the first complete Czech translation of the Bible was finished around 1360.The first complete printed Czech Bible was published in 1488.The first complete Czech Bible translation from the original languages was published between 1579 and 1593.The Codex Gigas from the 12th century is the largest extant medieval manuscript in the world.Jaroslav Seifert, winner of the Nobel Prize for LiteratureCzech-language literature can be divided into several periods: the Middle Ages; the Hussite period; the Renaissance humanism; the Baroque period; the Enlightenment and Czech reawakening in the first half of the 19th century, modern literature in the second half of the 19th century; the avant-garde of the interwar period; the years under Communism; and the Czech Republic.The antiwar comedy novel ''The Good Soldier Švejk'' is the most translated Czech book in history.The international literary award the Franz Kafka Prize is awarded in the Czech Republic.The Czech Republic has the densest network of libraries in Europe.Czech literature and culture played a role on at least two occasions when Czechs lived under oppression and political activity was suppressed.", "On both of these occasions, in the early 19th century and then again in the 1960s, the Czechs used their cultural and literary effort to strive for political freedom, establishing a confident, politically aware nation.=== Music ===Antonín DvořákThe musical tradition of the Czech lands arose from the first church hymns, whose first evidence is suggested at the break of the 10th and 11th centuries.", "Some pieces of Czech music include two chorales, which in their time performed the function of anthems: \"Lord, Have Mercy on Us\" and the hymn \"Saint Wenceslaus\" or \"Saint Wenceslaus Chorale\".", "The authorship of the anthem \"Lord, Have Mercy on Us\" is ascribed by some historians to Saint Adalbert of Prague (sv.Vojtěch), bishop of Prague, living between 956 and 997.The wealth of musical culture lies in the classical music tradition during all historical periods, especially in the Baroque, Classicism, Romantic, modern classical music and in the traditional folk music of Bohemia, Moravia and Silesia.", "Since the early era of artificial music, Czech musicians and composers have been influenced the folk music of the region and dance.Czech music can be considered to have been \"beneficial\" in both the European and worldwide context, several times co-determined or even determined a newly arriving era in musical art, above all of Classical era, as well as by original attitudes in Baroque, Romantic and modern classical music.", "Some Czech musical works are ''The Bartered Bride'', ''New World Symphony'', ''Sinfonietta'' and ''Jenůfa''.A music festival in the country is Prague Spring International Music Festival of classical music, a permanent showcase for performing artists, symphony orchestras and chamber music ensembles of the world.=== Theatre ===The roots of Czech theatre can be found in the Middle Ages, especially in the cultural life of the Gothic period.", "In the 19th century, the theatre played a role in the national awakening movement and later, in the 20th century, it became a part of modern European theatre art.", "The original Czech cultural phenomenon came into being at the end of the 1950s.", "This project called Laterna magika, resulting in productions that combined theater, dance, and film in a poetic manner, considered the first multimedia art project in an international context.A drama is Karel Čapek's play ''R.U.R.", "'', which introduced the word \"robot\".The country has a tradition of puppet theater.", "In 2016, Czech and Slovak Puppetry was included on the UNESCO Intangible Cultural Heritage Lists.=== Film ===Hermína Týrlová, animator and film directorThe tradition of Czech cinematography started in the second half of the 1890s.", "Peaks of the production in the era of silent movies include the historical drama ''The Builder of the Temple'' and the social and erotic drama ''Erotikon'' directed by Gustav Machatý.", "The early Czech sound film era was productive, above all in mainstream genres, with the comedies of Martin Frič or Karel Lamač.", "There were dramatic movies sought internationally.Hermína Týrlová was a prominent Czech animator, screenwriter, and film director.", "She was often called the mother of Czech animation.", "Over the course of her career, she produced over 60 animated children's short films using puppets and the technique of stop motion animation.Before the German occupation, in 1933, filmmaker and animator established the first Czech animation studio \"IRE Film\" with her husband Karel Dodal.After the period of Nazi occupation and early communist official dramaturgy of socialist realism in movies at the turn of the 1940s and 1950s with fewer exceptions such as ''Krakatit'' or ''Men without wings'' (awarded by in 1946), an era of the Czech film began with animated films, performed in anglophone countries under the name \"The Fabulous World of Jules Verne\" from 1958, which combined acted drama with animation, and Jiří Trnka, the founder of the modern puppet film.", "This began a tradition of animated films (''Mole'' etc.", ").Oscar-winning director Miloš FormanIn the 1960s, the hallmark of Czechoslovak New Wave's films were improvised dialogues, black and absurd humor and the occupation of non-actors.", "Directors are trying to preserve natural atmosphere without refinement and artificial arrangement of scenes.", "A personality of the 1960s and the beginning of the 1970s with original manuscript and psychological impact is František Vláčil.", "Another international author is Jan Švankmajer, a filmmaker and artist whose work spans several media.", "He is a self-labeled surrealist known for animations and features.The Barrandov Studios in Prague are the largest film studios with film locations in the country.", "Filmmakers have come to Prague to shoot scenery no longer found in Berlin, Paris and Vienna.", "The city of Karlovy Vary was used as a location for the 2006 James Bond film Casino Royale.The Czech Lion is the highest Czech award for film achievement.", "Karlovy Vary International Film Festival is one of the film festivals that have been given competitive status by the FIAPF.", "Other film festivals held in the country include Febiofest, Jihlava International Documentary Film Festival, One World Film Festival, Zlín Film Festival and Fresh Film Festival.=== Media ===Headquarters of Czech TelevisionCzech journalists and media enjoy a degree of freedom.", "There are restrictions against writing in support of Nazism, racism or violating Czech law.", "The Czech press was ranked as the 40th most free press in the World Press Freedom Index by Reporters Without Borders in 2021.Radio Free Europe/Radio Liberty has its headquarters in Prague.Czech Television is the country's national public television broadcaster.", "It operates a number of channels, including ČT1, ČT2, and the 24-hour news channel ČT24, as well as the news website ct24.cz.", "As of 2020, it is the most watched broadcaster, followed by the private TV Nova and Prima TV.", "However, TV Nova features the most watched main news program and prime time program.", "Other public media services include the Czech Radio and the Czech News Agency.The best-selling daily national newspapers in 2020/21 are Blesk (average 703,000 daily readers), Mladá fronta DNES (average 461,000 daily readers), Právo (average 182,000 daily readers), Lidové noviny (average 163,000 daily readers) and Hospodářské noviny (average 162,000 daily readers).Most Czechs (87%) read their news online, with Seznam.cz, iDNES.cz, Novinky.cz, iPrima.cz and Seznam Zprávy.cz being the most visited as of 2021.=== Cuisine ===A mug of Pilsner Urquell, the first pilsner type of pale lager beer, brewed since 1842Czech cuisine is marked by an emphasis on meat dishes with pork, beef, and chicken.", "Goose, duck, rabbit, and venison are served.", "Fish is less common, with the occasional exception of fresh trout and carp, which is served at Christmas.There is a variety of local sausages, wurst, pâtés, and smoked and cured meats.", "Czech desserts include a variety of whipped cream, chocolate, and fruit pastries and tarts, crêpes, creme desserts and cheese, poppy-seed-filled and other types of traditional cakes such as ''buchty'', ''koláče'' and ''štrúdl''.Czech beer has a history extending more than a millennium; the earliest known brewery existed in 993.Today the Czech Republic has the highest beer consumption per capita in the world.", "The pilsner style beer (pils) originated in Plzeň, where the world's first blond lager Pilsner Urquell is still produced.", "It has served as the inspiration for more than two-thirds of the beer produced in the world today.", "The city of České Budějovice has similarly lent its name to its beer, known as Budweiser Budvar.The South Moravian region has been producing wine since the Middle Ages; about 94% of vineyards in the Czech Republic are Moravian.", "Aside from beer, slivovitz and wine, the Czech Republic also produces two liquors, Fernet Stock and Becherovka.", "Kofola is a non-alcoholic domestic cola soft drink which competes with Coca-Cola and Pepsi.=== Sport ===Hockey player Jaromír JágrThe two leading sports in the Czech Republic are football and ice hockey.", "The most watched sporting events are the Olympic tournament and World Championships of ice hockey.", "Other most popular sports include tennis, volleyball, floorball, golf, ball hockey, athletics, basketball and skiing.The country has won 15 gold medals in the Summer Olympics and nine in the Winter Games.", "(See Olympic history.)", "The Czech ice hockey team won the gold medal at the 1998 Winter Olympics and has won twelve gold medals at the World Championships, including three straight from 1999 to 2001.The Škoda Motorsport is engaged in competition racing since 1901 and has gained a number of titles with various vehicles around the world.", "MTX automobile company was formerly engaged in the manufacture of racing and formula cars since 1969.Hiking is a popular sport.", "The word for 'tourist' in Czech, ''turista'', also means 'trekker' or 'hiker'.", "For hikers, thanks to the more than 120-year-old tradition, there is the Czech Hiking Markers System of trail blazing, that has been adopted by countries worldwide.", "There is a network of around 40,000 km of marked short- and long-distance trails crossing the whole country and all the Czech mountains." ], [ "See also", "* List of Czech Republic-related topics* Outline of the Czech Republic" ], [ "Notes" ], [ "References", "=== Citations ====== General sources ===***" ], [ "Further reading", " * Hochman, Jiří (1998).", "''Historical dictionary of the Czech State''.", "Scarecrow Press.", "* Bryant, Chad. ''", "Prague: Belonging and the Modern City''.", "Cambridge MA: Harvard University Press, 2021." ], [ "External links", "* Governmental website* Presidential website* Senate* Portal of the Public Administration* #VisitCzechia – official tourist portal of the Czech Republic* Czechia – Central Intelligence Agency: ''The World Factbook''* *" ] ]

[ [ "Czechoslovakia" ], [ "Introduction", "'''Czechoslovakia''' (; Czech and , ''Česko-Slovensko'') was a landlocked state in Central Europe, created in 1918, when it declared its independence from Austria-Hungary.", "In 1938, after the Munich Agreement, the Sudetenland became part of Nazi Germany, while the country lost further territories to Hungary and Poland (the territories of southern Slovakia with a predominantly Hungarian population to Hungary and Zaolzie to Poland).", "Between 1939 and 1945, the state ceased to exist, as Slovakia proclaimed its independence and Carpathian Ruthenia became part of Hungary, while in the remainder of the Czech Lands, the German Protectorate of Bohemia and Moravia was proclaimed.", "In 1939, after the outbreak of World War II, former Czechoslovak President Edvard Beneš formed a government-in-exile and sought recognition from the Allies.After World War II, Czechoslovakia was reestablished under its pre-1938 borders, with the exception of Carpathian Ruthenia, which became part of the Ukrainian SSR (a republic of the Soviet Union).", "The Communist Party seized power in a coup in 1948.From 1948 to 1989, Czechoslovakia was part of the Eastern Bloc with a planned economy.", "Its economic status was formalized in membership of Comecon from 1949 and its defense status in the Warsaw Pact of 1955.A period of political liberalization in 1968, the Prague Spring, ended violently when the Soviet Union, assisted by other Warsaw Pact countries, invaded Czechoslovakia.", "In 1989, as Marxist–Leninist governments and communism were ending all over Central and Eastern Europe, Czechoslovaks peacefully deposed their communist government during the Velvet Revolution, which began on 17 November 1989 and ended 11 days later on 28 November when all of the top Communist leaders and Communist party itself resigned.", "On 31 December 1992, Czechoslovakia peacefully split into the two sovereign states of the Czech Republic and Slovakia." ], [ "Characteristics", ";Form of state*1918–1937: A democratic republic championed by Tomáš Masaryk.", "*1938–1939: After the annexation of Sudetenland by Nazi Germany in 1938, the region gradually turned into a state with loosened connections among the Czech, Slovak, and Ruthenian parts.", "A strip of southern Slovakia and Carpathian Ruthenia was redeemed by Hungary, and the Trans-Olza region was annexed by Poland.", "*1939–1945: The remainder of the state was dismembered and became split into the '''Protectorate of Bohemia and Moravia''' and the '''Slovak Republic''', while the rest of Carpathian Ruthenia was occupied and annexed by Hungary.", "A government-in-exile continued to exist in London, supported by the United Kingdom, United States and their Allies; after the German invasion of Soviet Union, it was also recognized by the Soviet Union.", "Czechoslovakia adhered to the Declaration by United Nations and was a founding member of the United Nations.", "*1946–1948: The country was governed by a coalition government with communist ministers, including the prime minister and the minister of interior.", "Carpathian Ruthenia was ceded to the Soviet Union.", "*1948–1989: The country became a Marxist-Leninist state under Soviet domination with a command economy.", "In 1960, the country officially became a socialist republic, the '''Czechoslovak Socialist Republic'''.", "It was a satellite state of the Soviet Union.", "*1989–1990: Czechoslovakia formally became a federal republic comprising the '''Czech Socialist Republic''' and the '''Slovak Socialist Republic'''.", "In late 1989, the communist rule came to an end during the Velvet Revolution followed by the re-establishment of a democratic parliamentary republic.", "*1990–1992: Shortly after the Velvet Revolution, the state was renamed the '''Czech and Slovak Federative Republic''', consisting of the Czech Republic and the Slovak Republic (Slovakia) until the peaceful dissolution on 31 December 1992.;Neighbors*Austria 1918–1938, 1945–1992*Germany (both predecessors, West Germany and East Germany, were neighbors between 1949 and 1990)*Hungary*Poland*Romania 1918–1938*Soviet Union 1945–1991*Ukraine 1991–1992 (Soviet Union member until 1991);TopographyThe country was of generally irregular terrain.", "The western area was part of the north-central European uplands.", "The eastern region was composed of the northern reaches of the Carpathian Mountains and lands of the Danube River basin.", ";ClimateThe weather is mild winters and mild summers.", "Influenced by the Atlantic Ocean from the west, the Baltic Sea from the north, and Mediterranean Sea from the south.", "There is no continental weather." ], [ "Names", "*1918–1938: '''Czechoslovak Republic''' (abbreviated ČSR), or Czechoslovakia, before the formalization of the name in 1920, also known as Czecho-Slovakia or the Czecho-Slovak state*1938–1939: '''Czecho-Slovak Republic''', or Czecho-Slovakia*1945–1960: '''Czechoslovak Republic''' (ČSR), or Czechoslovakia*1960–1990: '''Czechoslovak Socialist Republic''' (ČSSR), or Czechoslovakia*1990: '''Czechoslovak Federative Republic''' (ČSFR)*1990–1992: '''Czech and Slovak Federative Republic''' (ČSFR), or Czechoslovakia" ], [ "History", "===Origins===Tomáš Garrigue Masaryk, founder and first presidentCzechoslovak troops in Vladivostok (1918)Czechoslovak declaration of independence rally in Prague on Wenceslas Square, 28 October 1918The area was part of the Austro-Hungarian Empire until it collapsed at the end of World War I.", "The new state was founded by Tomáš Garrigue Masaryk, who served as its first president from 14 November 1918 to 14 December 1935.He was succeeded by his close ally Edvard Beneš (1884–1948).The roots of Czech nationalism go back to the 19th century, when philologists and educators, influenced by Romanticism, promoted the Czech language and pride in the Czech people.", "Nationalism became a mass movement in the second half of the 19th century.", "Taking advantage of the limited opportunities for participation in political life under Austrian rule, Czech leaders such as historian František Palacký (1798–1876) founded various patriotic, self-help organizations which provided a chance for many of their compatriots to participate in communal life before independence.", "Palacký supported Austro-Slavism and worked for a reorganized federal Austrian Empire, which would protect the Slavic speaking peoples of Central Europe against Russian and German threats.An advocate of democratic reform and Czech autonomy within Austria-Hungary, Masaryk was elected twice to the ''Reichsrat'' (Austrian Parliament), from 1891 to 1893 for the Young Czech Party, and from 1907 to 1914 for the Czech Realist Party, which he had founded in 1889 with Karel Kramář and Josef Kaizl.During World War I a number of Czechs and Slovaks, the Czechoslovak Legions, fought with the Allies in France and Italy, while large numbers deserted to Russia in exchange for its support for the independence of Czechoslovakia from the Austrian Empire.", "With the outbreak of World War I, Masaryk began working for Czech independence in a union with Slovakia.", "With Edvard Beneš and Milan Rastislav Štefánik, Masaryk visited several Western countries and won support from influential publicists.", "The Czechoslovak National Council was the main organization that advanced the claims for a Czechoslovak state.===First Czechoslovak Republic===A monument to Tomáš Garrigue Masaryk and Milan Štefánik—both key figures in early Czechoslovakia====Formation====Czechoslovakia in 1928The Bohemian Kingdom ceased to exist in 1918 when it was incorporated into Czechoslovakia.", "Czechoslovakia was founded in October 1918, as one of the successor states of the Austro-Hungarian Empire at the end of World War I and as part of the Treaty of Saint-Germain-en-Laye.", "It consisted of the present day territories of Bohemia, Moravia, parts of Silesia making up present day Czech Republic, Slovakia, and a region of present day Ukraine called Carpathian Ruthenia.", "Its territory included some of the most industrialized regions of the former Austria-Hungary.==== Ethnicity ====Linguistic map of Czechoslovakia in 1930The new country was a multi-ethnic state, with Czechs and Slovaks as ''constituent peoples''.", "The population consisted of Czechs (51%), Slovaks (16%), Germans (22%), Hungarians (5%) and Rusyns (4%).", "Many of the Germans, Hungarians, Ruthenians and Poles and some Slovaks, felt oppressed because the political elite did not generally allow political autonomy for minority ethnic groups.", "This policy led to unrest among the non-Czech population, particularly in German-speaking Sudetenland, which initially had proclaimed itself part of the Republic of German-Austria in accordance with the self-determination principle.The state proclaimed the official ideology that there were no separate Czech and Slovak nations, but only one nation of Czechoslovaks (see Czechoslovakism), to the disagreement of Slovaks and other ethnic groups.", "Once a unified Czechoslovakia was restored after World War II (after the country had been divided during the war), the conflict between the Czechs and the Slovaks surfaced again.", "The governments of Czechoslovakia and other Central European nations deported ethnic Germans, reducing the presence of minorities in the nation.", "Most of the Jews had been killed during the war by the Nazis.----Ethnicities of Czechoslovakia in 1921---- Czecho slovaks 8,759,701 64.37% Germans 3,123,305 22.95% Hungarians 744,621 5.47% Ruthenians 461,449 3.39% Jews 180,534 1.33% Poles 75,852 0.56% Others 23,139 0.17% Foreigners 238,784 1.75% Total population 13,607,385--------Ethnicities of Czechoslovakia in 1930---- Czecho slovaks 10,066,000 68.35% Germans 3,229,000 21.93% Ruthenians 745,000 5.06% Hungarians 653,000 4.43% Jews 354,000 2.40% Poles 76,000 0.52% Romanians 14,000 0.10% Foreigners 239,000 1.62% Total population 14,726,158----''*Jews identified themselves as Germans or Hungarians (and Jews only by religion not ethnicity), the sum is, therefore, more than 100%.", "''=== Interwar period ===During the period between the two world wars Czechoslovakia was a democratic state.", "The population was generally literate, and contained fewer alienated groups.", "The influence of these conditions was augmented by the political values of Czechoslovakia's leaders and the policies they adopted.", "Under Tomas Masaryk, Czech and Slovak politicians promoted progressive social and economic conditions that served to defuse discontent.Foreign minister Beneš became the prime architect of the Czechoslovak-Romanian-Yugoslav alliance (the \"Little Entente\", 1921–38) directed against Hungarian attempts to reclaim lost areas.", "Beneš worked closely with France.", "Far more dangerous was the German element, which after 1933 became allied with the Nazis in Germany.Czech-Slovak relations came to be a central issue in Czechoslovak politics during the 1930s.", "The increasing feeling of inferiority among the Slovaks, who were hostile to the more numerous Czechs, weakened the country in the late 1930s.", "Slovakia became autonomous in the fall of 1938, and by mid-1939, Slovakia had become independent, with the First Slovak Republic set up as a satellite state of Nazi Germany and the far-right Slovak People's Party in power .After 1933, Czechoslovakia remained the only democracy in central and eastern Europe.===Munich Agreement, and Two-Step German Occupation===The partition of Czechoslovakia after Munich AgreementThe car in which Reinhard Heydrich was fatally injured in 1942Territory of the Second Czechoslovak Republic (1938–1939)In September 1938, Adolf Hitler demanded control of the Sudetenland.", "On 29 September 1938, Britain and France ceded control in the Appeasement at the Munich Conference; France ignored the military alliance it had with Czechoslovakia.", "During October 1938, Nazi Germany occupied the Sudetenland border region, effectively crippling Czechoslovak defences.The First Vienna Award assigned a strip of southern Slovakia and Carpathian Ruthenia to Hungary.", "Poland occupied Zaolzie, an area whose population was majority Polish, in October 1938.On 14 March 1939, the remainder (\"rump\") of Czechoslovakia was dismembered by the proclamation of the Slovak State, the next day the rest of Carpathian Ruthenia was occupied and annexed by Hungary, while the following day the German Protectorate of Bohemia and Moravia was proclaimed.The eventual goal of the German state under Nazi leadership was to eradicate Czech nationality through assimilation, deportation, and extermination of the Czech intelligentsia; the intellectual elites and middle class made up a considerable number of the 200,000 people who passed through concentration camps and the 250,000 who died during German occupation.", "Under , it was assumed that around 50% of Czechs would be fit for Germanization.", "The Czech intellectual elites were to be removed not only from Czech territories but from Europe completely.", "The authors of Generalplan Ost believed it would be best if they emigrated overseas, as even in Siberia they were considered a threat to German rule.", "Just like Jews, Poles, Serbs, and several other nations, Czechs were considered to be untermenschen by the Nazi state.", "In 1940, in a secret Nazi plan for the Germanization of the Protectorate of Bohemia and Moravia it was declared that those considered to be of racially Mongoloid origin and the Czech intelligentsia were not to be Germanized.The deportation of Jews to concentration camps was organized under the direction of Reinhard Heydrich, and the fortress town of Terezín was made into a ghetto way station for Jewish families.", "On 4 June 1942 Heydrich died after being wounded by an assassin in Operation Anthropoid.", "Heydrich's successor, Colonel General Kurt Daluege, ordered mass arrests and executions and the destruction of the villages of Lidice and Ležáky.", "In 1943 the German war effort was accelerated.", "Under the authority of Karl Hermann Frank, German minister of state for Bohemia and Moravia, some 350,000 Czech laborers were dispatched to the Reich.", "Within the protectorate, all non-war-related industry was prohibited.", "Most of the Czech population obeyed quiescently up until the final months preceding the end of the war, while thousands were involved in the resistance movement.For the Czechs of the Protectorate Bohemia and Moravia, German occupation was a period of brutal oppression.", "Czech losses resulting from political persecution and deaths in concentration camps totaled between 36,000 and 55,000.The Jewish populations of Bohemia and Moravia (118,000 according to the 1930 census) were virtually annihilated.", "Many Jews emigrated after 1939; more than 70,000 were killed; 8,000 survived at Terezín.", "Several thousand Jews managed to live in freedom or in hiding throughout the occupation.Despite the estimated 136,000 deaths at the hands of the Nazi regime, the population in the Reichsprotektorate saw a net increase during the war years of approximately 250,000 in line with an increased birth rate.On 6 May 1945, the third US Army of General Patton entered Pilsen from the south west.", "On 9 May 1945, Soviet Red Army troops entered Prague.===Communist Czechoslovakia===coat of arms in 1960–1989After World War II, prewar Czechoslovakia was reestablished, with the exception of Subcarpathian Ruthenia, which was annexed by the Soviet Union and incorporated into the Ukrainian Soviet Socialist Republic.", "The Beneš decrees were promulgated concerning ethnic Germans (see Potsdam Agreement) and ethnic Hungarians.", "Under the decrees, citizenship was abrogated for people of German and Hungarian ethnic origin who had accepted German or Hungarian citizenship during the occupations.", "In 1948, this provision was cancelled for the Hungarians, but only partially for the Germans.", "The government then confiscated the property of the Germans and expelled about 90% of the ethnic German population, over 2 million people.", "Those who remained were collectively accused of supporting the Nazis after the Munich Agreement, as 97.32% of Sudeten Germans had voted for the NSDAP in the December 1938 elections.", "Almost every decree explicitly stated that the sanctions did not apply to antifascists.", "Some 250,000 Germans, many married to Czechs, some antifascists, and also those required for the post-war reconstruction of the country, remained in Czechoslovakia.", "The Beneš Decrees still cause controversy among nationalist groups in the Czech Republic, Germany, Austria and Hungary.Following the expulsion of the ethnic German population from Czechoslovakia, parts of the former Sudetenland, especially around Krnov and the surrounding villages of the Jesenik mountain region in northeastern Czechoslovakia, were settled in 1949 by Communist refugees from Northern Greece who had left their homeland as a result of the Greek Civil War.", "These Greeks made up a large proportion of the town and region's population until the late 1980s/early 1990s.", "Although defined as \"Greeks\", the Greek Communist community of Krnov and the Jeseniky region actually consisted of an ethnically diverse population, including Greek Macedonians, Macedonians, Vlachs, Pontic Greeks and Turkish speaking Urums or Caucasus Greeks.Spartakiad'' in 1960Carpathian Ruthenia (Podkarpatská Rus) was occupied by (and in June 1945 formally ceded to) the Soviet Union.", "In the 1946 parliamentary election, the Communist Party of Czechoslovakia was the winner in the Czech lands, and the Democratic Party won in Slovakia.", "In February 1948 the Communists seized power.", "Although they would maintain the fiction of political pluralism through the existence of the National Front, except for a short period in the late 1960s (the Prague Spring) the country had no liberal democracy.", "Since citizens lacked significant electoral methods of registering protest against government policies, periodically there were street protests that became violent.", "For example, there were riots in the town of Plzeň in 1953, reflecting economic discontent.", "Police and army units put down the rebellion, and hundreds were injured but no one was killed.", "While its economy remained more advanced than those of its neighbors in Eastern Europe, Czechoslovakia grew increasingly economically weak relative to Western Europe.The currency reform of 1953 caused dissatisfaction among Czechoslovak laborers.", "To equalize the wage rate, Czechoslovaks had to turn in their old money for new at a decreased value.", "The banks also confiscated savings and bank deposits to control the amount of money in circulation.", "In the 1950s, Czechoslovakia experienced high economic growth (averaging 7% per year), which allowed for a substantial increase in wages and living standards, thus promoting the stability of the regime.Czechoslovakia after 1969In 1968, when the reformer Alexander Dubček was appointed to the key post of First Secretary of the Czechoslovak Communist Party, there was a brief period of liberalization known as the Prague Spring.", "In response, after failing to persuade the Czechoslovak leaders to change course, five other members of the Warsaw Pact invaded.", "Soviet tanks rolled into Czechoslovakia on the night of 20–21 August 1968.Soviet Communist Party General Secretary Leonid Brezhnev viewed this intervention as vital for the preservation of the Soviet, socialist system and vowed to intervene in any state that sought to replace Marxism-Leninism with capitalism.In the week after the invasion there was a spontaneous campaign of civil resistance against the occupation.", "This resistance involved a wide range of acts of non-cooperation and defiance: this was followed by a period in which the Czechoslovak Communist Party leadership, having been forced in Moscow to make concessions to the Soviet Union, gradually put the brakes on their earlier liberal policies.Meanwhile, one plank of the reform program had been carried out: in 1968–69, Czechoslovakia was turned into a federation of the Czech Socialist Republic and Slovak Socialist Republic.", "The theory was that under the federation, social and economic inequities between the Czech and Slovak halves of the state would be largely eliminated.", "A number of ministries, such as education, now became two formally equal bodies in the two formally equal republics.", "However, the centralized political control by the Czechoslovak Communist Party severely limited the effects of federalization.The 1970s saw the rise of the dissident movement in Czechoslovakia, represented among others by Václav Havel.", "The movement sought greater political participation and expression in the face of official disapproval, manifested in limitations on work activities, which went as far as a ban on professional employment, the refusal of higher education for the dissidents' children, police harassment and prison.During the 1980s, Czechoslovakia became one of the most tightly controlled Communist regimes in the Warsaw Pact in resistance to the mitigation of controls notified by Soviet president Mikhail Gorbachev.===After 1989===The Visegrád Group signing ceremony in February 1991In 1989, the Velvet Revolution restored democracy.", "This occurred around the same time as the fall of communism in Romania, Bulgaria, Hungary, East Germany and Poland.The word \"socialist\" was removed from the country's full name on 29 March 1990 and replaced by \"federal\".Pope John Paul II made a papal visit to Czechoslovakia on 21 April 1990, hailing it as a symbolic step of reviving Christianity in the newly-formed post-communist state.Czechoslovakia participated in the Gulf War with a small force of 200 troops under the command of the U.S.-led coalition.In 1992, because of growing nationalist tensions in the government, Czechoslovakia was peacefully dissolved by parliament.", "On 31 December 1992 it formally separated into two independent countries, the Czech Republic and the Slovak Republic." ], [ "Government and politics", "After World War II, a political monopoly was held by the Communist Party of Czechoslovakia (KSČ).", "The leader of the KSČ was ''de facto'' the most powerful person in the country during this period.", "Gustáv Husák was elected first secretary of the KSČ in 1969 (changed to general secretary in 1971) and president of Czechoslovakia in 1975.Other parties and organizations existed but functioned in subordinate roles to the KSČ.", "All political parties, as well as numerous mass organizations, were grouped under umbrella of the National Front.", "Human rights activists and religious activists were severely repressed.Federal Assembly in Prague===Constitutional development===coat of arms in 1990–1992Czechoslovakia had the following constitutions during its history (1918–1992):*Temporary constitution of 14 November 1918 (democratic): see History of Czechoslovakia (1918–1938)*The 1920 constitution (The Constitutional Document of the Czechoslovak Republic), democratic, in force until 1948, several amendments*The Communist 1948 Ninth-of-May Constitution*The Communist 1960 Constitution of the Czechoslovak Socialist Republic with major amendments in 1968 (Constitutional Law of Federation), 1971, 1975, 1978, and 1989 (at which point the leading role of the Communist Party was abolished).", "It was amended several more times during 1990–1992 (for example, 1990, name change to Czecho-Slovakia, 1991 incorporation of the human rights charter)=== Heads of state and government ===*List of presidents of Czechoslovakia*List of prime ministers of Czechoslovakia===Foreign policy=======International agreements and membership====In the 1930s, the nation formed a military alliance with France, which collapsed in the Munich Agreement of 1938.After World War II, an active participant in Council for Mutual Economic Assistance (Comecon), Warsaw Pact, United Nations and its specialized agencies; signatory of conference on Security and Cooperation in Europe.===Administrative divisions===*1918–1923: Different systems in former Austrian territory (Bohemia, Moravia, a small part of Silesia) compared to former Hungarian territory (Slovakia and Ruthenia): three lands (''země'') (also called district units (''kraje'')): Bohemia, Moravia, Silesia, plus 21 counties (''župy'') in today's Slovakia and three counties in today's Ruthenia; both lands and counties were divided into districts (''okresy'').", "*1923–1927: As above, except that the Slovak and Ruthenian counties were replaced by six (grand) counties (''(veľ)župy'') in Slovakia and one (grand) county in Ruthenia, and the numbers and boundaries of the ''okresy'' were changed in those two territories.", "*1928–1938: Four lands (Czech: ''země'', Slovak: ''krajiny''): Bohemia, Moravia-Silesia, Slovakia and Sub-Carpathian Ruthenia, divided into districts (''okresy'').", "*Late 1938 – March 1939: As above, but Slovakia and Ruthenia gained the status of \"autonomous lands\".", "Slovakia was called ''Slovenský štát'', with its own currency and government.", "*1945–1948: As in 1928–1938, except that Ruthenia became part of the Soviet Union.", "*1949–1960: 19 regions (''kraje'') divided into 270 ''okresy''.", "*1960–1992: 10 ''kraje'', Prague, and (from 1970) Bratislava (capital of Slovakia); these were divided into 109–114 okresy; the kraje were abolished temporarily in Slovakia in 1969–1970 and for many purposes from 1991 in Czechoslovakia; in addition, the Czech Socialist Republic and the Slovak Socialist Republic were established in 1969 (without the word ''Socialist'' from 1990)." ], [ "Population and ethnic groups" ], [ "Economy", "Before World War II, the economy was about the fourth in all industrial countries in Europe.", "The state was based on strong economy, manufacturing cars (Škoda, Tatra), trams, aircraft (Aero, Avia), ships, ship engines (Škoda), cannons, shoes (Baťa), turbines, guns (Zbrojovka Brno).", "It was the industrial workshop for the Austro-Hungarian empire.", "The Slovak lands relied more heavily on agriculture than the Czech lands.After World War II, the economy was centrally planned, with command links controlled by the communist party, similarly to the Soviet Union.", "The large metallurgical industry was dependent on imports of iron and non-ferrous ores.", "*Industry: Extractive industry and manufacturing dominated the sector, including machinery, chemicals, food processing, metallurgy, and textiles.", "The sector was wasteful in its use of energy, materials, and labor and was slow to upgrade technology, but the country was a major supplier of high-quality machinery, instruments, electronics, aircraft, airplane engines and arms to other socialist countries.", "*Agriculture: Agriculture was a minor sector, but collectivized farms of large acreage and relatively efficient mode of production enabled the country to be relatively self-sufficient in the food supply.", "The country depended on imports of grains (mainly for livestock feed) in years of adverse weather.", "Meat production was constrained by a shortage of feed, but the country still recorded high per capita consumption of meat.", "*Foreign Trade: Exports were estimated at US$17.8 billion in 1985.Exports were machinery (55%), fuel and materials (14%), and manufactured consumer goods (16%).", "Imports stood at an estimated US$17.9 billion in 1985, including fuel and materials (41%), machinery (33%), and agricultural and forestry products (12%).", "In 1986, about 80% of foreign trade was with other socialist countries.", "*Exchange rate: Official, or commercial, the rate was crowns (Kčs) 5.4 per US$1 in 1987.Tourist, or non-commercial, the rate was Kčs 10.5 per US$1.Neither rate reflected purchasing power.", "The exchange rate on the black market was around Kčs 30 per US$1, which became the official rate once the currency became convertible in the early 1990s.", "*Fiscal year: Calendar year.", "*Fiscal policy: The state was the exclusive owner of means of production in most cases.", "Revenue from state enterprises was the primary source of revenues followed by turnover tax.", "The government spent heavily on social programs, subsidies, and investment.", "The budget was usually balanced or left a small surplus." ], [ "Resource base", "After World War II, the country was short of energy, relying on imported crude oil and natural gas from the Soviet Union, domestic brown coal, and nuclear and hydroelectric energy.", "Energy constraints were a major factor in the 1980s." ], [ "Transport and communications", "Slightly after the foundation of Czechoslovakia in 1918, there was a lack of essential infrastructure in many areas – paved roads, railways, bridges, etc.", "Massive improvement in the following years enabled Czechoslovakia to develop its industry.", "Prague's civil airport in Ruzyně became one of the most modern terminals in the world when it was finished in 1937.Tomáš Baťa, a Czech entrepreneur and visionary, outlined his ideas in the publication \"Budujme stát pro 40 milionů lidí\", where he described the future motorway system.", "Construction of the first motorways in Czechoslovakia begun in 1939, nevertheless, they were stopped after German occupation during World War II." ], [ "Society" ], [ "Education", "Education was free at all levels and compulsory from ages 6 to 15.The vast majority of the population was literate.", "There was a highly developed system of apprenticeship training and vocational schools supplemented general secondary schools and institutions of higher education." ], [ "Religion", "In 1991, 46% of the population were Roman Catholics, 5.3% were Evangelical Lutheran, 30% were Atheist, and other religions made up 17% of the country, but there were huge differences in religious practices between the two constituent republics; see Czech Republic and Slovakia." ], [ "Health, social welfare and housing", "After World War II, free health care was available to all citizens.", "National health planning emphasized preventive medicine; factory and local health care centres supplemented hospitals and other inpatient institutions.", "There was a substantial improvement in rural health care during the 1960s and 1970s." ], [ "Mass media", "During the era between the World Wars, Czechoslovak democracy and liberalism facilitated conditions for free publication.", "The most significant daily newspapers in these times were Lidové noviny, Národní listy, Český deník and Československá Republika.During Communist rule, the mass media in Czechoslovakia were controlled by the Communist Party.", "Private ownership of any publication or agency of the mass media was generally forbidden, although churches and other organizations published small periodicals and newspapers.", "Even with this information monopoly in the hands of organizations under KSČ control, all publications were reviewed by the government's Office for Press and Information." ], [ "Sports", "Czechoslovak national football team in 1966The Czechoslovakia national football team was a consistent performer on the international scene, with eight appearances in the FIFA World Cup Finals, finishing in second place in 1934 and 1962.The team also won the European Football Championship in 1976, came in third in 1980 and won the Olympic gold in 1980.Well-known football players such as Pavel Nedvěd, Antonín Panenka, Milan Baroš, Tomáš Rosický, Vladimír Šmicer or Petr Čech were all born in Czechoslovakia.The International Olympic Committee code for Czechoslovakia is TCH, which is still used in historical listings of results.The Czechoslovak national ice hockey team won many medals from the world championships and Olympic Games.", "Peter Šťastný, Jaromír Jágr, Dominik Hašek, Peter Bondra, Petr Klíma, Marián Gáborík, Marián Hossa, Miroslav Šatan and Pavol Demitra all come from Czechoslovakia.Emil Zátopek, winner of four Olympic gold medals in athletics, is considered one of the top athletes in Czechoslovak history.Věra Čáslavská was an Olympic gold medallist in gymnastics, winning seven gold medals and four silver medals.", "She represented Czechoslovakia in three consecutive Olympics.Several accomplished professional tennis players including Jaroslav Drobný, Ivan Lendl, Jan Kodeš, Miloslav Mečíř, Hana Mandlíková, Martina Hingis, Martina Navratilova, Jana Novotna, Petra Kvitová and Daniela Hantuchová were born in Czechoslovakia." ], [ "Culture", "*Czech RepublicSlovakia*List of CzechsList of Slovaks*MDŽ (International Women's Day)*Jazz in dissident Czechoslovakia" ], [ "Postage stamps", "*Postage stamps and postal history of Czechoslovakia* Czechoslovakia stamp reused by Slovak Republic after 18 January 1939 by overprinting country and value" ], [ "See also", "*Effects on the environment in Czechoslovakia from Soviet influence during the Cold War*Former countries in Europe after 1815*List of former sovereign states" ], [ "Notes" ], [ "References" ], [ "Sources", "*" ], [ "Further reading", "*Heimann, Mary.", "''Czechoslovakia: The State That Failed'' (2009).", "*Hermann, A. H. ''A History of the Czechs'' (1975).", "*Kalvoda, Josef.", "''The Genesis of Czechoslovakia'' (1986).", "*Leff, Carol Skalnick.", "''National Conflict in Czechoslovakia: The Making and Remaking of a State, 1918–87'' (1988).", "*Mantey, Victor.", "''A History of the Czechoslovak Republic'' (1973).", "*Myant, Martin.", "''The Czechoslovak Economy, 1948–88'' (1989).", "*Naimark, Norman, and Leonid Gibianskii, eds.", "''The Establishment of Communist Regimes in Eastern Europe, 1944–1949'' (1997) online edition*Orzoff, Andrea.", "''Battle for the Castle: The Myth of Czechoslovakia in Europe 1914–1948'' (Oxford University Press, 2009); online review online*Paul, David.", "''Czechoslovakia: Profile of a Socialist Republic at the Crossroads of Europe'' (1990).", "*Renner, Hans.", "''A History of Czechoslovakia since 1945'' (1989).", "*Seton-Watson, R. W. ''A History of the Czechs and Slovaks'' (1943).", "*Stone, Norman, and E. Strouhal, eds.", "''Czechoslovakia: Crossroads and Crises, 1918–88'' (1989).", "*Wheaton, Bernard; Zdenek Kavav.", "\"The Velvet Revolution: Czechoslovakia, 1988–1991\" (1992).", "*Williams, Kieran, \"Civil Resistance in Czechoslovakia: From Soviet Invasion to \"Velvet Revolution\", 1968–89\",in Adam Roberts and Timothy Garton Ash (eds.", "), ''Civil Resistance and Power Politics: The Experience of Non-violent Action from Gandhi to the Present'' (Oxford University Press, 2009).", "*Windsor, Philip, and Adam Roberts, ''Czechoslovakia 1968: Reform, Repression and Resistance'' (1969).", "*Wolchik, Sharon L. ''Czechoslovakia: Politics, Society, and Economics'' (1990)." ], [ "External links", "* Online books and articles * U.S. Library of Congress Country Studies, \"Czechoslovakia\"*English/Czech: Orders and Medals of Czechoslovakia including Order of the White Lion* Czechoslovakia by Encyclopædia Britannica* Katrin Boeckh: Crumbling of Empires and Emerging States: Czechoslovakia and Yugoslavia as (Multi)national Countries, in: 1914-1918-online.", "International Encyclopedia of the First World War.Maps with Hungarian-language rubrics:* Border changes after the creation of Czechoslovakia* Interwar Czechoslovakia* Czechoslovakia after Munich Agreement" ] ]

[ [ "Computer science" ], [ "Introduction", "'''Computer science''' is the study of computation, information, and automation.", "Computer science spans theoretical disciplines (such as algorithms, theory of computation, and information theory) to applied disciplines (including the design and implementation of hardware and software).", "Though more often considered an academic discipline, computer science is closely related to computer programming.Algorithms and data structures are central to computer science.The theory of computation concerns abstract models of computation and general classes of problems that can be solved using them.", "The fields of cryptography and computer security involve studying the means for secure communication and for preventing security vulnerabilities.", "Computer graphics and computational geometry address the generation of images.", "Programming language theory considers different ways to describe computational processes, and database theory concerns the management of repositories of data.", "Human–computer interaction investigates the interfaces through which humans and computers interact, and software engineering focuses on the design and principles behind developing software.", "Areas such as operating systems, networks and embedded systems investigate the principles and design behind complex systems.", "Computer architecture describes the construction of computer components and computer-operated equipment.", "Artificial intelligence and machine learning aim to synthesize goal-orientated processes such as problem-solving, decision-making, environmental adaptation, planning and learning found in humans and animals.", "Within artificial intelligence, computer vision aims to understand and process image and video data, while natural language processing aims to understand and process textual and linguistic data.The fundamental concern of computer science is determining what can and cannot be automated.", "The Turing Award is generally recognized as the highest distinction in computer science." ], [ "History", "Gottfried Wilhelm Leibniz (1646–1716) developed logic in a binary number system and has been called the \"founder of computer science\".Charles Babbage is sometimes referred to as the \"father of computing\".", "Ada Lovelace published the first algorithm intended for processing on a computer.", "The earliest foundations of what would become computer science predate the invention of the modern digital computer.", "Machines for calculating fixed numerical tasks such as the abacus have existed since antiquity, aiding in computations such as multiplication and division.", "Algorithms for performing computations have existed since antiquity, even before the development of sophisticated computing equipment.Wilhelm Schickard designed and constructed the first working mechanical calculator in 1623.In 1673, Gottfried Leibniz demonstrated a digital mechanical calculator, called the Stepped Reckoner.", "Leibniz may be considered the first computer scientist and information theorist, because of various reasons, including the fact that he documented the binary number system.", "In 1820, Thomas de Colmar launched the mechanical calculator industry when he invented his simplified arithmometer, the first calculating machine strong enough and reliable enough to be used daily in an office environment.", "Charles Babbage started the design of the first ''automatic mechanical calculator'', his Difference Engine, in 1822, which eventually gave him the idea of the first ''programmable mechanical calculator'', his Analytical Engine.", "He started developing this machine in 1834, and \"in less than two years, he had sketched out many of the salient features of the modern computer\".", "\"A crucial step was the adoption of a punched card system derived from the Jacquard loom\" making it infinitely programmable.", "In 1843, during the translation of a French article on the Analytical Engine, Ada Lovelace wrote, in one of the many notes she included, an algorithm to compute the Bernoulli numbers, which is considered to be the first published algorithm ever specifically tailored for implementation on a computer.", "Around 1885, Herman Hollerith invented the tabulator, which used punched cards to process statistical information; eventually his company became part of IBM.", "Following Babbage, although unaware of his earlier work, Percy Ludgate in 1909 published the 2nd of the only two designs for mechanical analytical engines in history.", "In 1914, the Spanish engineer Leonardo Torres Quevedo published his ''Essays on Automatics'', and designed, inspired by Babbage, a theoretical electromechanical calculating machine which was to be controlled by a read-only program.", "The paper also introduced the idea of floating-point arithmetic.", "In 1920, to celebrate the 100th anniversary of the invention of the arithmometer, Torres presented in Paris the Electromechanical Arithmometer, a prototype that demonstrated the feasibility of an electromechanical analytical engine, on which commands could be typed and the results printed automatically.", "In 1937, one hundred years after Babbage's impossible dream, Howard Aiken convinced IBM, which was making all kinds of punched card equipment and was also in the calculator business to develop his giant programmable calculator, the ASCC/Harvard Mark I, based on Babbage's Analytical Engine, which itself used cards and a central computing unit.", "When the machine was finished, some hailed it as \"Babbage's dream come true\".During the 1940s, with the development of new and more powerful computing machines such as the Atanasoff–Berry computer and ENIAC, the term ''computer'' came to refer to the machines rather than their human predecessors.", "As it became clear that computers could be used for more than just mathematical calculations, the field of computer science broadened to study computation in general.", "In 1945, IBM founded the Watson Scientific Computing Laboratory at Columbia University in New York City.", "The renovated fraternity house on Manhattan's West Side was IBM's first laboratory devoted to pure science.", "The lab is the forerunner of IBM's Research Division, which today operates research facilities around the world.", "Ultimately, the close relationship between IBM and Columbia University was instrumental in the emergence of a new scientific discipline, with Columbia offering one of the first academic-credit courses in computer science in 1946.Computer science began to be established as a distinct academic discipline in the 1950s and early 1960s.", "The world's first computer science degree program, the Cambridge Diploma in Computer Science, began at the University of Cambridge Computer Laboratory in 1953.The first computer science department in the United States was formed at Purdue University in 1962.Since practical computers became available, many applications of computing have become distinct areas of study in their own rights." ], [ "Etymology and scope", "Although first proposed in 1956, the term \"computer science\" appears in a 1959 article in ''Communications of the ACM'',in which Louis Fein argues for the creation of a ''Graduate School in Computer Sciences'' analogous to the creation of Harvard Business School in 1921.Louis justifies the name by arguing that, like management science, the subject is applied and interdisciplinary in nature, while having the characteristics typical of an academic discipline.His efforts, and those of others such as numerical analyst George Forsythe, were rewarded: universities went on to create such departments, starting with Purdue in 1962.Despite its name, a significant amount of computer science does not involve the study of computers themselves.", "Because of this, several alternative names have been proposed.", "Certain departments of major universities prefer the term ''computing science'', to emphasize precisely that difference.", "Danish scientist Peter Naur suggested the term ''datalogy'', to reflect the fact that the scientific discipline revolves around data and data treatment, while not necessarily involving computers.", "The first scientific institution to use the term was the Department of Datalogy at the University of Copenhagen, founded in 1969, with Peter Naur being the first professor in datalogy.", "The term is used mainly in the Scandinavian countries.", "An alternative term, also proposed by Naur, is data science; this is now used for a multi-disciplinary field of data analysis, including statistics and databases.In the early days of computing, a number of terms for the practitioners of the field of computing were suggested in the ''Communications of the ACM''—''turingineer'', ''turologist'', ''flow-charts-man'', ''applied meta-mathematician'', and ''applied epistemologist''.", "Three months later in the same journal, ''comptologist'' was suggested, followed next year by ''hypologist''.", "The term ''computics'' has also been suggested.", "In Europe, terms derived from contracted translations of the expression \"automatic information\" (e.g.", "\"informazione automatica\" in Italian) or \"information and mathematics\" are often used, e.g.", "''informatique'' (French), ''Informatik'' (German), ''informatica'' (Italian, Dutch), ''informática'' (Spanish, Portuguese), ''informatika'' (Slavic languages and Hungarian) or ''pliroforiki'' (''πληροφορική'', which means informatics) in Greek.", "Similar words have also been adopted in the UK (as in the School of Informatics, University of Edinburgh).", "\"In the U.S., however, informatics is linked with applied computing, or computing in the context of another domain.", "\"A folkloric quotation, often attributed to—but almost certainly not first formulated by—Edsger Dijkstra, states that \"computer science is no more about computers than astronomy is about telescopes.\"", "The design and deployment of computers and computer systems is generally considered the province of disciplines other than computer science.", "For example, the study of computer hardware is usually considered part of computer engineering, while the study of commercial computer systems and their deployment is often called information technology or information systems.", "However, there has been exchange of ideas between the various computer-related disciplines.", "Computer science research also often intersects other disciplines, such as cognitive science, linguistics, mathematics, physics, biology, Earth science, statistics, philosophy, and logic.Computer science is considered by some to have a much closer relationship with mathematics than many scientific disciplines, with some observers saying that computing is a mathematical science.", "Early computer science was strongly influenced by the work of mathematicians such as Kurt Gödel, Alan Turing, John von Neumann, Rózsa Péter and Alonzo Church and there continues to be a useful interchange of ideas between the two fields in areas such as mathematical logic, category theory, domain theory, and algebra.The relationship between computer science and software engineering is a contentious issue, which is further muddied by disputes over what the term \"software engineering\" means, and how computer science is defined.", "David Parnas, taking a cue from the relationship between other engineering and science disciplines, has claimed that the principal focus of computer science is studying the properties of computation in general, while the principal focus of software engineering is the design of specific computations to achieve practical goals, making the two separate but complementary disciplines.The academic, political, and funding aspects of computer science tend to depend on whether a department is formed with a mathematical emphasis or with an engineering emphasis.", "Computer science departments with a mathematics emphasis and with a numerical orientation consider alignment with computational science.", "Both types of departments tend to make efforts to bridge the field educationally if not across all research." ], [ "Philosophy", "===Epistemology of computer science===Despite the word \"science\" in its name, there is debate over whether or not computer science is a discipline of science, mathematics, or engineering.", "Allen Newell and Herbert A. Simon argued in 1975, It has since been argued that computer science can be classified as an empirical science since it makes use of empirical testing to evaluate the correctness of programs, but a problem remains in defining the laws and theorems of computer science (if any exist) and defining the nature of experiments in computer science.", "Proponents of classifying computer science as an engineering discipline argue that the reliability of computational systems is investigated in the same way as bridges in civil engineering and airplanes in aerospace engineering.", "They also argue that while empirical sciences observe what presently exists, computer science observes what is possible to exist and while scientists discover laws from observation, no proper laws have been found in computer science and it is instead concerned with creating phenomena.Proponents of classifying computer science as a mathematical discipline argue that computer programs are physical realizations of mathematical entities and programs can be deductively reasoned through mathematical formal methods.", "Computer scientists Edsger W. Dijkstra and Tony Hoare regard instructions for computer programs as mathematical sentences and interpret formal semantics for programming languages as mathematical axiomatic systems.===Paradigms of computer science===A number of computer scientists have argued for the distinction of three separate paradigms in computer science.", "Peter Wegner argued that those paradigms are science, technology, and mathematics.", "Peter Denning's working group argued that they are theory, abstraction (modeling), and design.", "Amnon H. Eden described them as the \"rationalist paradigm\" (which treats computer science as a branch of mathematics, which is prevalent in theoretical computer science, and mainly employs deductive reasoning), the \"technocratic paradigm\" (which might be found in engineering approaches, most prominently in software engineering), and the \"scientific paradigm\" (which approaches computer-related artifacts from the empirical perspective of natural sciences, identifiable in some branches of artificial intelligence).Computer science focuses on methods involved in design, specification, programming, verification, implementation and testing of human-made computing systems." ], [ "Fields", "As a discipline, computer science spans a range of topics from theoretical studies of algorithms and the limits of computation to the practical issues of implementing computing systems in hardware and software.CSAB, formerly called Computing Sciences Accreditation Board—which is made up of representatives of the Association for Computing Machinery (ACM), and the IEEE Computer Society (IEEE CS)—identifies four areas that it considers crucial to the discipline of computer science: ''theory of computation'', ''algorithms and data structures'', ''programming methodology and languages'', and ''computer elements and architecture''.", "In addition to these four areas, CSAB also identifies fields such as software engineering, artificial intelligence, computer networking and communication, database systems, parallel computation, distributed computation, human–computer interaction, computer graphics, operating systems, and numerical and symbolic computation as being important areas of computer science.===Theoretical computer science===''Theoretical Computer Science'' is mathematical and abstract in spirit, but it derives its motivation from the practical and everyday computation.", "Its aim is to understand the nature of computation and, as a consequence of this understanding, provide more efficient methodologies.====Theory of computation====According to Peter Denning, the fundamental question underlying computer science is, \"What can be automated?\"", "Theory of computation is focused on answering fundamental questions about what can be computed and what amount of resources are required to perform those computations.", "In an effort to answer the first question, computability theory examines which computational problems are solvable on various theoretical models of computation.", "The second question is addressed by computational complexity theory, which studies the time and space costs associated with different approaches to solving a multitude of computational problems.The famous P = NP?", "problem, one of the Millennium Prize Problems, is an open problem in the theory of computation.", "130px 96px 120px Automata theory Formal languages Computability theory Computational complexity theory 96px 96px File:XNOR ANSI Labelled.svg 96px Models of computation Quantum computing theory Logic circuit theory Cellular automata====Information and coding theory====Information theory, closely related to probability and statistics, is related to the quantification of information.", "This was developed by Claude Shannon to find fundamental limits on signal processing operations such as compressing data and on reliably storing and communicating data.Coding theory is the study of the properties of codes (systems for converting information from one form to another) and their fitness for a specific application.", "Codes are used for data compression, cryptography, error detection and correction, and more recently also for network coding.", "Codes are studied for the purpose of designing efficient and reliable data transmission methods.", "96px 96px 96px 96px 96px Coding theory Channel capacity Algorithmic information theory Signal detection theory Kolmogorov complexity====Data structures and algorithms====Data structures and algorithms are the studies of commonly used computational methods and their computational efficiency.", "96px 96px 96px 96px 96px Analysis of algorithms Algorithm design Data structures Combinatorial optimization Computational geometry Randomized algorithms====Programming language theory and formal methods====Programming language theory is a branch of computer science that deals with the design, implementation, analysis, characterization, and classification of programming languages and their individual features.", "It falls within the discipline of computer science, both depending on and affecting mathematics, software engineering, and linguistics.", "It is an active research area, with numerous dedicated academic journals.Formal methods are a particular kind of mathematically based technique for the specification, development and verification of software and hardware systems.", "The use of formal methods for software and hardware design is motivated by the expectation that, as in other engineering disciplines, performing appropriate mathematical analysis can contribute to the reliability and robustness of a design.", "They form an important theoretical underpinning for software engineering, especially where safety or security is involved.", "Formal methods are a useful adjunct to software testing since they help avoid errors and can also give a framework for testing.", "For industrial use, tool support is required.", "However, the high cost of using formal methods means that they are usually only used in the development of high-integrity and life-critical systems, where safety or security is of utmost importance.", "Formal methods are best described as the application of a fairly broad variety of theoretical computer science fundamentals, in particular logic calculi, formal languages, automata theory, and program semantics, but also type systems and algebraic data types to problems in software and hardware specification and verification.", "96px 96px 96px 96px 96px Formal semantics Type theory Compiler design Programming languages Formal verification Automated theorem proving===Applied computer science=======Computer graphics and visualization====Computer graphics is the study of digital visual contents and involves the synthesis and manipulation of image data.", "The study is connected to many other fields in computer science, including computer vision, image processing, and computational geometry, and is heavily applied in the fields of special effects and video games.", "96px 96px 96px 96px 96px 96px 2D computer graphics Computer animation Rendering Mixed reality Virtual reality Solid modeling====Image and sound processing====Information can take the form of images, sound, video or other multimedia.", "Bits of information can be streamed via signals.", "Its processing is the central notion of informatics, the European view on computing, which studies information processing algorithms independently of the type of information carrier – whether it is electrical, mechanical or biological.", "This field plays important role in information theory, telecommunications, information engineering and has applications in medical image computing and speech synthesis, among others.", "''What is the lower bound on the complexity of fast Fourier transform algorithms?''", "is one of unsolved problems in theoretical computer science.", "96px 96px 96px 96px 96px 96px FFT algorithms Image processing Speech recognition Data compression Medical image computing Speech synthesis====Computational science, finance and engineering====Scientific computing (or computational science) is the field of study concerned with constructing mathematical models and quantitative analysis techniques and using computers to analyze and solve scientific problems.", "A major usage of scientific computing is simulation of various processes, including computational fluid dynamics, physical, electrical, and electronic systems and circuits, as well as societies and social situations (notably war games) along with their habitats, among many others.", "Modern computers enable optimization of such designs as complete aircraft.", "Notable in electrical and electronic circuit design are SPICE, as well as software for physical realization of new (or modified) designs.", "The latter includes essential design software for integrated circuits.", "96px 96px 96px 96px 96px 96px 75px 94px 75px Numerical analysis Computational physics Computational chemistry Bioinformatics Neuroinformatics Psychoinformatics Medical informatics Computational engineering Computational musicology====Social computing and human–computer interaction====Social computing is an area that is concerned with the intersection of social behavior and computational systems.", "Human–computer interaction research develops theories, principles, and guidelines for user interface designers.====Software engineering====Software engineering is the study of designing, implementing, and modifying the software in order to ensure it is of high quality, affordable, maintainable, and fast to build.", "It is a systematic approach to software design, involving the application of engineering practices to software.", "Software engineering deals with the organizing and analyzing of software—it does not just deal with the creation or manufacture of new software, but its internal arrangement and maintenance.", "For example software testing, systems engineering, technical debt and software development processes.====Artificial intelligence====Artificial intelligence (AI) aims to or is required to synthesize goal-orientated processes such as problem-solving, decision-making, environmental adaptation, learning, and communication found in humans and animals.", "From its origins in cybernetics and in the Dartmouth Conference (1956), artificial intelligence research has been necessarily cross-disciplinary, drawing on areas of expertise such as applied mathematics, symbolic logic, semiotics, electrical engineering, philosophy of mind, neurophysiology, and social intelligence.", "AI is associated in the popular mind with robotic development, but the main field of practical application has been as an embedded component in areas of software development, which require computational understanding.", "The starting point in the late 1940s was Alan Turing's question \"Can computers think?", "\", and the question remains effectively unanswered, although the Turing test is still used to assess computer output on the scale of human intelligence.", "But the automation of evaluative and predictive tasks has been increasingly successful as a substitute for human monitoring and intervention in domains of computer application involving complex real-world data.", "96px 96px 96px 96px Computational learning theory Computer vision Neural networks Planning and scheduling 96px 96px 96px 96px Natural language processing Computational game theory Evolutionary computation Autonomic computing 96px 96px 100px 96px Representation and reasoning Pattern recognition Robotics Swarm intelligence===Computer systems=======Computer architecture and organization====Computer architecture, or digital computer organization, is the conceptual design and fundamental operational structure of a computer system.", "It focuses largely on the way by which the central processing unit performs internally and accesses addresses in memory.", "Computer engineers study computational logic and design of computer hardware, from individual processor components, microcontrollers, personal computers to supercomputers and embedded systems.", "The term \"architecture\" in computer literature can be traced to the work of Lyle R. Johnson and Frederick P. Brooks Jr., members of the Machine Organization department in IBM's main research center in 1959.96px 96px 96px 96px Processing unit Microarchitecture Multiprocessing Processor design 96px 96px 96px 96px Ubiquitous computing Systems architecture Operating systems Input/output 96px 96px 96px 96px Embedded system Real-time computing Dependability Interpreter====Concurrent, parallel and distributed computing====Concurrency is a property of systems in which several computations are executing simultaneously, and potentially interacting with each other.", "A number of mathematical models have been developed for general concurrent computation including Petri nets, process calculi and the Parallel Random Access Machine model.", "When multiple computers are connected in a network while using concurrency, this is known as a distributed system.", "Computers within that distributed system have their own private memory, and information can be exchanged to achieve common goals.====Computer networks====This branch of computer science aims to manage networks between computers worldwide.====Computer security and cryptography====Computer security is a branch of computer technology with the objective of protecting information from unauthorized access, disruption, or modification while maintaining the accessibility and usability of the system for its intended users.Historical cryptography is the art of writing and deciphering secret messages.", "Modern cryptography is the scientific study of problems relating to distributed computations that can be attacked.", "Technologies studied in modern cryptography include symmetric and asymmetric encryption, digital signatures, cryptographic hash functions, key-agreement protocols, blockchain, zero-knowledge proofs, and garbled circuits.====Databases and data mining====A database is intended to organize, store, and retrieve large amounts of data easily.", "Digital databases are managed using database management systems to store, create, maintain, and search data, through database models and query languages.", "Data mining is a process of discovering patterns in large data sets." ], [ "Discoveries", "The philosopher of computing Bill Rapaport noted three ''Great Insights of Computer Science'':* Gottfried Wilhelm Leibniz's, George Boole's, Alan Turing's, Claude Shannon's, and Samuel Morse's insight: there are only ''two objects'' that a computer has to deal with in order to represent \"anything\".", ":: All the information about any computable problem can be represented using only 0 and 1 (or any other bistable pair that can flip-flop between two easily distinguishable states, such as \"on/off\", \"magnetized/de-magnetized\", \"high-voltage/low-voltage\", etc.).", "* Alan Turing's insight: there are only ''five actions'' that a computer has to perform in order to do \"anything\".", ":: Every algorithm can be expressed in a language for a computer consisting of only five basic instructions:::* move left one location;::* move right one location;::* read symbol at current location;::* print 0 at current location;::* print 1 at current location.", "* Corrado Böhm and Giuseppe Jacopini's insight: there are only ''three ways of combining'' these actions (into more complex ones) that are needed in order for a computer to do \"anything\".", ":: Only three rules are needed to combine any set of basic instructions into more complex ones:::*''sequence'': first do this, then do that;::* '' selection'': IF such-and-such is the case, THEN do this, ELSE do that;::* ''repetition'': WHILE such-and-such is the case, DO this.", ":: The three rules of Boehm's and Jacopini's insight can be further simplified with the use of goto (which means it is more elementary than structured programming)." ], [ "Programming paradigms", "Programming languages can be used to accomplish different tasks in different ways.", "Common programming paradigms include:* Functional programming, a style of building the structure and elements of computer programs that treats computation as the evaluation of mathematical functions and avoids state and mutable data.", "It is a declarative programming paradigm, which means programming is done with expressions or declarations instead of statements.", "* Imperative programming, a programming paradigm that uses statements that change a program's state.", "In much the same way that the imperative mood in natural languages expresses commands, an imperative program consists of commands for the computer to perform.", "Imperative programming focuses on describing how a program operates.", "* Object-oriented programming, a programming paradigm based on the concept of \"objects\", which may contain data, in the form of fields, often known as attributes; and code, in the form of procedures, often known as methods.", "A feature of objects is that an object's procedures can access and often modify the data fields of the object with which they are associated.", "Thus object-oriented computer programs are made out of objects that interact with one another.", "* Service-oriented programming, a programming paradigm that uses \"services\" as the unit of computer work, to design and implement integrated business applications and mission critical software programsMany languages offer support for multiple paradigms, making the distinction more a matter of style than of technical capabilities." ], [ "Research", "Conferences are important events for computer science research.", "During these conferences, researchers from the public and private sectors present their recent work and meet.", "Unlike in most other academic fields, in computer science, the prestige of conference papers is greater than that of journal publications.", "One proposed explanation for this is the quick development of this relatively new field requires rapid review and distribution of results, a task better handled by conferences than by journals." ], [ "Education", "'''Computer Science''', known by its near synonyms, '''Computing''', '''Computer Studies''', has been taught in UK schools since the days of batch processing, mark sensitive cards and paper tape but usually to a select few students.", "In 1981, the BBC produced a micro-computer and classroom network and Computer Studies became common for GCE O level students (11–16-year-old), and Computer Science to A level students.", "Its importance was recognised, and it became a compulsory part of the National Curriculum, for Key Stage 3 & 4.In September 2014 it became an entitlement for all pupils over the age of 4.In the US, with 14,000 school districts deciding the curriculum, provision was fractured.", "According to a 2010 report by the Association for Computing Machinery (ACM) and Computer Science Teachers Association (CSTA), only 14 out of 50 states have adopted significant education standards for high school computer science.", "According to a 2021 report, only 51% of high schools in the US offer computer science.Israel, New Zealand, and South Korea have included computer science in their national secondary education curricula, and several others are following." ], [ "See also", "* Glossary of computer science* List of computer scientists* List of computer science awards* List of pioneers in computer science* Outline of computer science" ], [ "Notes" ], [ "References" ], [ "Further reading", "* * * * * * * * * * Peter J. Denning. ''", "Is computer science science?", "'', Communications of the ACM, April 2005.", "* Peter J. Denning, '' Great principles in computing curricula'', Technical Symposium on Computer Science Education, 2004." ], [ "External links", "* DBLP Computer Science Bibliography* Association for Computing Machinery* Institute of Electrical and Electronics Engineers" ] ]

[ [ "Catalan" ], [ "Introduction", "'''Catalan''' may refer to:" ], [ "Catalonia", "From, or related to Catalonia:* Catalan language, a Romance language* Catalans, an ethnic group formed by the people from, or with origins in, Northern or southern Catalonia" ], [ "Places", "* 13178 Catalan, asteroid #13178, named \"Catalan\"* Catalán (crater), a lunar crater named for Miguel Ángel Catalán* Çatalan, İvrindi, a village in Balıkesir province, Turkey* Çatalan, Karaisalı, a village in Adana Province, Turkey* Catalan Bay, Gibraltar* Catalan Sea, more commonly known as the Balearic Sea* Catalan Mediterranean System, the Catalan Mountains===Facilities and structures===* Çatalan Bridge, Adana, Turkey* Çatalan Dam, Adana, Turkey* Catalan Batteries, Gibraltar" ], [ "People", "* Catalan, Lord of Monaco (1415–1457), Lord of Monaco from 1454 until 1457* Alfredo Catalán (born 1968), Venezuelan politician* Alex Catalán (born 1968), Spanish filmmaker* Arnaut Catalan (1219–1253), troubador* Diego Catalán (1928–2008), Spanish philologist* Emilio Arenales Catalán (1922–1969) Guatemalan politician* Eugène Charles Catalan (1814–1894), French and Belgian mathematician* Miguel A. Catalán (1894–1957), Spanish spectroscopist* Moses Chayyim Catalan (died 1661), Italian rabbi* Sergio Catalán (born 1991) Chilean soccer player" ], [ "Mathematics", "Mathematical concepts named after mathematician Eugène Catalan:* Catalan numbers, a sequence of natural numbers that occur in various counting problems* Catalan solids, a family of polyhedra* Catalan's constant, a number that occurs in estimates in combinatorics* Catalan's conjecture" ], [ "Wine", "* Catalan (grape), another name for the wine grape Mourvèdre* Catalan wine, an alternative name used in France for wine made from the Carignan grape** Carignan, a wine grape that is also known as Catalan" ], [ "Sports and games", "* Catalan Opening, in chess* Catalan Open, golf tournament* Catalans Dragons, a rugby league team often known simply as ''Catalan''* XIII Catalan, a rugby league team from Perpignan, France" ], [ "Other uses", "* Battle of Catalán (1817) in Uruguay * Catalan Sheepdog* Catalan Company, medieval mercenary company* Catalan vault, architectural design element* ''The Catalans'', a 1953 novel by Patrick O'Brian" ], [ "See also", "* ***Catalonia (disambiguation)*Catalunya (disambiguation)* Catalan exonyms* Anti-Catalanism" ] ]

[ [ "Creationism" ], [ "Introduction", "'''Creationism''' is the religious belief that nature, and aspects such as the universe, Earth, life, and humans, originated with supernatural acts of divine creation.", "In its broadest sense, creationism includes a continuum of religious views, which vary in their acceptance or rejection of scientific explanations such as evolution that describe the origin and development of natural phenomena.The term ''creationism'' most often refers to belief in special creation; the claim that the universe and lifeforms were created as they exist today by divine action, and that the only true explanations are those which are compatible with a Christian fundamentalist literal interpretation of the creation myth found in the Bible's Genesis creation narrative.", "Since the 1970s, the most common form of this has been Young Earth creationism which posits special creation of the universe and lifeforms within the last 10,000 years on the basis of flood geology, and promotes pseudoscientific creation science.", "From the 18th century onward, Old Earth creationism accepted geological time harmonized with Genesis through gap or day-age theory, while supporting anti-evolution.", "Modern old-Earth creationists support progressive creationism and continue to reject evolutionary explanations.", "Following political controversy, creation science was reformulated as intelligent design and neo-creationism.Mainline Protestants and the Catholic Church reconcile modern science with their faith in Creation through forms of theistic evolution which hold that God purposefully created through the laws of nature, and accept evolution.", "Some groups call their belief evolutionary creationism.", "Less prominently, there are also members of the Islamic and Hindu faiths who are creationists.", "Use of the term \"creationist\" in this context dates back to Charles Darwin's unpublished 1842 sketch draft for what became ''On the Origin of Species'', and he used the term later in letters to colleagues.", "In 1873, Asa Gray published an article in ''The Nation'' saying a \"special creationist\" who held that species \"were supernaturally originated just as they are, by the very terms of his doctrine places them out of the reach of scientific explanation.\"" ], [ "Biblical basis", "The basis for many creationists' beliefs is a literal or quasi-literal interpretation of the Book of Genesis.", "The Genesis creation narratives (Genesis 1–2) describe how God brings the Universe into being in a series of creative acts over six days and places the first man and woman (Adam and Eve) in the Garden of Eden.", "This story is the basis of creationist cosmology and biology.", "The Genesis flood narrative (Genesis 6–9) tells how God destroys the world and all life through a great flood, saving representatives of each form of life by means of Noah's Ark.", "This forms the basis of creationist geology, better known as flood geology.Recent decades have seen attempts to de-link creationism from the Bible and recast it as science; these include creation science and intelligent design." ], [ "Types", "To counter the common misunderstanding that the creation–evolution controversy was a simple dichotomy of views, with \"creationists\" set against \"evolutionists\", Eugenie Scott of the National Center for Science Education produced a diagram and description of a continuum of religious views as a spectrum ranging from extreme literal biblical creationism to materialist evolution, grouped under main headings.", "This was used in public presentations, then published in 1999 in ''Reports of the NCSE''.", "Other versions of a taxonomy of creationists were produced, and comparisons made between the different groupings.", "In 2009 Scott produced a revised continuum taking account of these issues, emphasizing that intelligent design creationism overlaps other types, and each type is a grouping of various beliefs and positions.", "The revised diagram is labelled to shows a spectrum relating to positions on the age of the Earth, and the part played by special creation as against evolution.", "This was published in the book ''Evolution Vs. Creationism: An Introduction'', and the NCSE website rewritten on the basis of the book version.The main general types are listed below.+ Comparison of major creationist viewsHumanityBiological speciesEarthAge of Universe Young Earth creationism Directly created by God.", "Directly created by God.", "Macroevolution does not occur.Less than 10,000 years old.", "Reshaped by global flood.Less than 10,000 years old, but some hold this view only for the Solar System.", "Gap creationismScientifically accepted age.", "Reshaped by global flood.Scientifically accepted age.", "Progressive creationismDirectly created by God, based on primate anatomy.Direct creation + evolution.", "No single common ancestor.Scientifically accepted age.", "No global flood.Scientifically accepted age.", "Intelligent designProponents hold various beliefs.", "(For example, Michael Behe accepts evolution from primates.", ")Divine intervention at some point in the past, as evidenced by what intelligent-design creationists call \"irreducible complexity.\"", "Some adherents accept common descent, others do not.", "Some claim the existence of Earth is the result of divine intervention.Scientifically accepted age.", "Theistic evolution (evolutionary creationism)Evolution from primates.Evolution from single common ancestor.Scientifically accepted age.", "No global flood.Scientifically accepted age.===Young Earth creationism===The Creation Museum is a young Earth creationism museum run by Answers in Genesis (AiG) in Petersburg, Kentucky, United States.The ICR Discovery Center for Science & Earth History is a young Earth creationist museum run by Institute for Creation Research (ICR) in Dallas, Texas, United States.Young Earth creationists such as Ken Ham and Doug Phillips believe that God created the Earth within the last ten thousand years, with a literalist interpretation of the Genesis creation narrative, within the approximate time-frame of biblical genealogies.", "Most young Earth creationists believe that the universe has a similar age as the Earth.", "A few assign a much older age to the universe than to Earth.", "Young Earth creationism gives the universe an age consistent with the Ussher chronology and other young Earth time frames.", "Other young Earth creationists believe that the Earth and the universe were created with the appearance of age, so that the world appears to be much older than it is, and that this appearance is what gives the geological findings and other methods of dating the Earth and the universe their much longer timelines.The Christian organizations Answers in Genesis (AiG), Institute for Creation Research (ICR) and the Creation Research Society (CRS) promote young Earth creationism in the United States.", "Carl Baugh's Creation Evidence Museum in Texas, United States AiG's Creation Museum and Ark Encounter in Kentucky, United States were opened to promote young Earth creationism.", "Creation Ministries International promotes young Earth views in Australia, Canada, South Africa, New Zealand, the United States, and the United Kingdom.Among Roman Catholics, the Kolbe Center for the Study of Creation promotes similar ideas.===Old Earth creationism===Old Earth creationism holds that the physical universe was created by God, but that the creation event described in the Book of Genesis is to be taken figuratively.", "This group generally believes that the age of the universe and the age of the Earth are as described by astronomers and geologists, but that details of modern evolutionary theory are questionable.Old Earth creationism itself comes in at least three types:====Gap creationism====Gap creationism (also known as ''ruin-restoration creationism'', ''restoration creationism'', or ''the Gap Theory'') is a form of old Earth creationism that posits that the six-''yom'' creation period, as described in the Book of Genesis, involved six literal 24-hour days, but that there was a gap of time between two distinct creations in the first and the second verses of Genesis, which the theory states explains many scientific observations, including the age of the Earth.", "Thus, the six days of creation (verse 3 onwards) start sometime after the Earth was \"without form and void.\"", "This allows an indefinite gap of time to be inserted after the original creation of the universe, but prior to the Genesis creation narrative, (when present biological species and humanity were created).", "Gap theorists can therefore agree with the scientific consensus regarding the age of the Earth and universe, while maintaining a literal interpretation of the biblical text.Some gap creationists expand the basic version of creationism by proposing a \"primordial creation\" of biological life within the \"gap\" of time.", "This is thought to be \"the world that then was\" mentioned in 2 Peter 3:3–6.Discoveries of fossils and archaeological ruins older than 10,000 years are generally ascribed to this \"world that then was,\" which may also be associated with Lucifer's rebellion.====Day-age creationism====Day-age creationism, a type of old Earth creationism, is a metaphorical interpretation of the creation accounts in Genesis.", "It holds that the six days referred to in the Genesis account of creation are not ordinary 24-hour days, but are much longer periods (from thousands to billions of years).", "The Genesis account is then reconciled with the age of the Earth.", "Proponents of the day-age theory can be found among both theistic evolutionists, who accept the scientific consensus on evolution, and progressive creationists, who reject it.", "The theories are said to be built on the understanding that the Hebrew word ''yom'' is also used to refer to a time period, with a beginning and an end and not necessarily that of a 24-hour day.The day-age theory attempts to reconcile the Genesis creation narrative and modern science by asserting that the creation \"days\" were not ordinary 24-hour days, but actually lasted for long periods of time (as day-age implies, the \"days\" each lasted an age).", "According to this view, the sequence and duration of the creation \"days\" may be paralleled to the scientific consensus for the age of the earth and the universe.====Progressive creationism====Progressive creationism is the religious belief that God created new forms of life gradually over a period of hundreds of millions of years.", "As a form of old Earth creationism, it accepts mainstream geological and cosmological estimates for the age of the Earth, some tenets of biology such as microevolution as well as archaeology to make its case.", "In this view creation occurred in rapid bursts in which all \"kinds\" of plants and animals appear in stages lasting millions of years.", "The bursts are followed by periods of stasis or equilibrium to accommodate new arrivals.", "These bursts represent instances of God creating new types of organisms by divine intervention.", "As viewed from the archaeological record, progressive creationism holds that \"species do not gradually appear by the steady transformation of its ancestors; but appear all at once and \"fully formed.", "\"The view rejects macroevolution, claiming it is biologically untenable and not supported by the fossil record, as well as rejects the concept of common descent from a last universal common ancestor.", "Thus the evidence for macroevolution is claimed to be false, but microevolution is accepted as a genetic parameter designed by the Creator into the fabric of genetics to allow for environmental adaptations and survival.", "Generally, it is viewed by proponents as a middle ground between literal creationism and evolution.", "Organizations such as Reasons To Believe, founded by Hugh Ross, promote this version of creationism.Progressive creationism can be held in conjunction with hermeneutic approaches to the Genesis creation narrative such as the day-age creationism or framework/metaphoric/poetic views.===Philosophic and scientific creationism=======Creation science====Creation science, or initially scientific creationism, is a pseudoscience that emerged in the 1960s with proponents aiming to have young Earth creationist beliefs taught in school science classes as a counter to teaching of evolution.", "Common features of creation science argument include: creationist cosmologies which accommodate a universe on the order of thousands of years old, criticism of radiometric dating through a technical argument about radiohalos, explanations for the fossil record as a record of the Genesis flood narrative (see flood geology), and explanations for the present diversity as a result of pre-designed genetic variability and partially due to the rapid degradation of the perfect genomes God placed in \"created kinds\" or \"baramins\" due to mutations.====Neo-creationism====Neo-creationism is a pseudoscientific movement which aims to restate creationism in terms more likely to be well received by the public, by policy makers, by educators and by the scientific community.", "It aims to re-frame the debate over the origins of life in non-religious terms and without appeals to scripture.", "This comes in response to the 1987 ruling by the United States Supreme Court in ''Edwards v. Aguillard'' that creationism is an inherently religious concept and that advocating it as correct or accurate in public-school curricula violates the Establishment Clause of the First Amendment.One of the principal claims of neo-creationism propounds that ostensibly objective orthodox science, with a foundation in naturalism, is actually a dogmatically atheistic religion.", "Its proponents argue that the scientific method excludes certain explanations of phenomena, particularly where they point towards supernatural elements, thus effectively excluding religious insight from contributing to understanding the universe.", "This leads to an open and often hostile opposition to what neo-creationists term \"Darwinism\", which they generally mean to refer to evolution, but which they may extend to include such concepts as abiogenesis, stellar evolution and the Big Bang theory.Unlike their philosophical forebears, neo-creationists largely do not believe in many of the traditional cornerstones of creationism such as a young Earth, or in a dogmatically literal interpretation of the Bible.====Intelligent design====Intelligent design (ID) is the pseudoscientific view that \"certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection.\"", "All of its leading proponents are associated with the Discovery Institute, a think tank whose wedge strategy aims to replace the scientific method with \"a science consonant with Christian and theistic convictions\" which accepts supernatural explanations.", "It is widely accepted in the scientific and academic communities that intelligent design is a form of creationism, and is sometimes referred to as \"intelligent design creationism.", "\"ID originated as a re-branding of creation science in an attempt to avoid a series of court decisions ruling out the teaching of creationism in American public schools, and the Discovery Institute has run a series of campaigns to change school curricula.", "In Australia, where curricula are under the control of state governments rather than local school boards, there was a public outcry when the notion of ID being taught in science classes was raised by the Federal Education Minister Brendan Nelson; the minister quickly conceded that the correct forum for ID, if it were to be taught, is in religious or philosophy classes.In the US, teaching of intelligent design in public schools has been decisively ruled by a federal district court to be in violation of the Establishment Clause of the First Amendment to the United States Constitution.", "In Kitzmiller v. Dover, the court found that intelligent design is not science and \"cannot uncouple itself from its creationist, and thus religious, antecedents,\" and hence cannot be taught as an alternative to evolution in public school science classrooms under the jurisdiction of that court.", "This sets a persuasive precedent, based on previous US Supreme Court decisions in ''Edwards v. Aguillard'' and ''Epperson v. Arkansas'' (1968), and by the application of the Lemon test, that creates a legal hurdle to teaching intelligent design in public school districts in other federal court jurisdictions.===Geocentrism===In astronomy, the geocentric model (also known as geocentrism, or the Ptolemaic system), is a description of the cosmos where Earth is at the orbital center of all celestial bodies.", "This model served as the predominant cosmological system in many ancient civilizations such as ancient Greece.", "As such, they assumed that the Sun, Moon, stars, and naked eye planets circled Earth, including the noteworthy systems of Aristotle (see Aristotelian physics) and Ptolemy.Articles arguing that geocentrism was the biblical perspective appeared in some early creation science newsletters associated with the Creation Research Society pointing to some passages in the Bible, which, when taken literally, indicate that the daily apparent motions of the Sun and the Moon are due to their actual motions around the Earth rather than due to the rotation of the Earth about its axis.", "For example, where the Sun and Moon are said to stop in the sky, and where the world is described as immobile.", "Contemporary advocates for such religious beliefs include Robert Sungenis, co-author of the self-published ''Galileo Was Wrong: The Church Was Right'' (2006).", "These people subscribe to the view that a plain reading of the Bible contains an accurate account of the manner in which the universe was created and requires a geocentric worldview.", "Most contemporary creationist organizations reject such perspectives.=== Omphalos hypothesis ===The Omphalos hypothesis is one attempt to reconcile the scientific evidence that the universe is billions of years old with a literal interpretation of the Genesis creation narrative, which implies that the Earth is only a few thousand years old.", "It is based on the religious belief that the universe was created by a divine being, within the past six to ten thousand years (in keeping with flood geology), and that the presence of objective, verifiable evidence that the universe is older than approximately ten millennia is due to the creator introducing false evidence that makes the universe appear significantly older.The idea was named after the title of an 1857 book, ''Omphalos'' by Philip Henry Gosse, in which Gosse argued that in order for the world to be functional God must have created the Earth with mountains and canyons, trees with growth rings, Adam and Eve with fully grown hair, fingernails, and navels (ὀμφαλός ''omphalos'' is Greek for \"navel\"), and all living creatures with fully formed evolutionary features, etc..., and that, therefore, ''no'' empirical evidence about the age of the Earth or universe can be taken as reliable.Various supporters of Young Earth creationism have given different explanations for their belief that the universe is filled with false evidence of the universe's age, including a belief that some things needed to be created at a certain age for the ecosystems to function, or their belief that the creator was deliberately planting deceptive evidence.", "The idea has seen some revival in the 20th century by some modern creationists, who have extended the argument to address the \"starlight problem\".", "The idea has been criticised as Last Thursdayism, and on the grounds that it requires a deliberately deceptive creator." ], [ "Theistic evolution", "Theistic evolution, or evolutionary creation, is a belief that \"the personal God of the Bible created the universe and life through evolutionary processes.\"", "According to the American Scientific Affiliation:Through the 19th century the term ''creationism'' most commonly referred to direct creation of individual souls, in contrast to traducianism.", "Following the publication of ''Vestiges of the Natural History of Creation'', there was interest in ideas of Creation by divine law.", "In particular, the liberal theologian Baden Powell argued that this illustrated the Creator's power better than the idea of miraculous creation, which he thought ridiculous.", "When ''On the Origin of Species'' was published, the cleric Charles Kingsley wrote of evolution as \"just as noble a conception of Deity.\"", "Darwin's view at the time was of God creating life through the laws of nature, and the book makes several references to \"creation,\" though he later regretted using the term rather than calling it an unknown process.", "In America, Asa Gray argued that evolution is the secondary effect, or ''modus operandi'', of the first cause, design, and published a pamphlet defending the book in theistic terms, ''Natural Selection not inconsistent with Natural Theology''.", "Theistic evolution, also called, evolutionary creation, became a popular compromise, and St. George Jackson Mivart was among those accepting evolution but attacking Darwin's naturalistic mechanism.", "Eventually it was realised that supernatural intervention could not be a scientific explanation, and naturalistic mechanisms such as neo-Lamarckism were favoured as being more compatible with purpose than natural selection.Some theists took the general view that, instead of faith being in opposition to biological evolution, some or all classical religious teachings about Christian God and creation are compatible with some or all of modern scientific theory, including specifically evolution; it is also known as \"evolutionary creation.\"", "In ''Evolution versus Creationism'', Eugenie Scott and Niles Eldredge state that it is in fact a type of evolution.It generally views evolution as a tool used by God, who is both the first cause and immanent sustainer/upholder of the universe; it is therefore well accepted by people of strong theistic (as opposed to deistic) convictions.", "Theistic evolution can synthesize with the day-age creationist interpretation of the Genesis creation narrative; however most adherents consider that the first chapters of the Book of Genesis should not be interpreted as a \"literal\" description, but rather as a literary framework or allegory.From a theistic viewpoint, the underlying laws of nature were designed by God for a purpose, and are so self-sufficient that the complexity of the entire physical universe evolved from fundamental particles in processes such as stellar evolution, life forms developed in biological evolution, and in the same way the origin of life by natural causes has resulted from these laws.In one form or another, theistic evolution is the view of creation taught at the majority of mainline Protestant seminaries.", "For Roman Catholics, human evolution is not a matter of religious teaching, and must stand or fall on its own scientific merits.", "Evolution and the Roman Catholic Church are not in conflict.", "The Catechism of the Catholic Church comments positively on the theory of evolution, which is neither precluded nor required by the sources of faith, stating that scientific studies \"have splendidly enriched our knowledge of the age and dimensions of the cosmos, the development of life-forms and the appearance of man.\"", "Roman Catholic schools teach evolution without controversy on the basis that scientific knowledge does not extend beyond the physical, and scientific truth and religious truth cannot be in conflict.", "Theistic evolution can be described as \"creationism\" in holding that divine intervention brought about the origin of life or that divine laws govern formation of species, though many creationists (in the strict sense) would deny that the position is creationism at all.", "In the creation–evolution controversy, its proponents generally take the \"evolutionist\" side.", "This sentiment was expressed by Fr.", "George Coyne, (the Vatican's chief astronomer between 1978 and 2006):...in America, creationism has come to mean some fundamentalistic, literal, scientific interpretation of Genesis.", "Judaic-Christian faith is radically creationist, but in a totally different sense.", "It is rooted in a belief that everything depends upon God, or better, all is a gift from God.While supporting the methodological naturalism inherent in modern science, the proponents of theistic evolution reject the implication taken by some atheists that this gives credence to ontological materialism.", "In fact, many modern philosophers of science, including atheists, refer to the long-standing convention in the scientific method that observable events in nature should be explained by natural causes, with the distinction that it does not assume the actual existence or non-existence of the supernatural." ], [ "Religious views", "There are also non-Christian forms of creationism, notably Islamic creationism and Hindu creationism.===Bahá'í Faith===In the creation myth taught by Bahá'u'lláh, the Bahá'í Faith founder, the universe has \"neither beginning nor ending,\" and that the component elements of the material world have always existed and will always exist.", "With regard to evolution and the origin of human beings, 'Abdu'l-Bahá gave extensive comments on the subject when he addressed western audiences in the beginning of the 20th century.", "Transcripts of these comments can be found in ''Some Answered Questions'', ''Paris Talks'' and ''The Promulgation of Universal Peace''.", "'Abdu'l-Bahá described the human species as having evolved from a primitive form to modern man, but that the capacity to form human intelligence was always in existence.===Buddhism===Buddhism denies a creator deity and posits that mundane deities such as Mahabrahma are sometimes misperceived to be a creator.", "While Buddhism includes belief in divine beings called devas, it holds that they are mortal, limited in their power, and that none of them are creators of the universe.", "In the Saṃyutta Nikāya, the Buddha also states that the cycle of rebirths stretches back hundreds of thousands of eons, without discernible beginning.Major Buddhist Indian philosophers such as Nagarjuna, Vasubandhu, Dharmakirti and Buddhaghosa, consistently critiqued Creator God views put forth by Hindu thinkers.===Christianity===, most Christians around the world accepted evolution as the most likely explanation for the origins of species, and did not take a literal view of the Genesis creation narrative.", "The United States is an exception where belief in religious fundamentalism is much more likely to affect attitudes towards evolution than it is for believers elsewhere.", "Political partisanship affecting religious belief may be a factor because political partisanship in the US is highly correlated with fundamentalist thinking, unlike in Europe.Most contemporary Christian leaders and scholars from mainstream churches, such as Anglicans and Lutherans, consider that there is no conflict between the spiritual meaning of creation and the science of evolution.", "According to the former archbishop of Canterbury, Rowan Williams, \"for most of the history of Christianity, and I think this is fair enough, most of the history of the Christianity there's been an awareness that a belief that everything depends on the creative act of God, is quite compatible with a degree of uncertainty or latitude about how precisely that unfolds in creative time.", "\"Leaders of the Anglican and Roman Catholic churches have made statements in favor of evolutionary theory, as have scholars such as the physicist John Polkinghorne, who argues that evolution is one of the principles through which God created living beings.", "Earlier supporters of evolutionary theory include Frederick Temple, Asa Gray and Charles Kingsley who were enthusiastic supporters of Darwin's theories upon their publication, and the French Jesuit priest and geologist Pierre Teilhard de Chardin saw evolution as confirmation of his Christian beliefs, despite condemnation from Church authorities for his more speculative theories.", "Another example is that of Liberal theology, not providing any creation models, but instead focusing on the symbolism in beliefs of the time of authoring Genesis and the cultural environment.Many Christians and Jews had been considering the idea of the creation history as an allegory (instead of historical) long before the development of Darwin's theory of evolution.", "For example, Philo, whose works were taken up by early Church writers, wrote that it would be a mistake to think that creation happened in six days, or in any set amount of time.", "Augustine of the late fourth century who was also a former neoplatonist argued that everything in the universe was created by God at the same moment in time (and not in six days as a literal reading of the Book of Genesis would seem to require); It appears that both Philo and Augustine felt uncomfortable with the idea of a seven-day creation because it detracted from the notion of God's omnipotence.", "In 1950, Pope Pius XII stated limited support for the idea in his encyclical .", "In 1996, Pope John Paul II stated that \"new knowledge has led to the recognition of the theory of evolution as more than a hypothesis,\" but, referring to previous papal writings, he concluded that \"if the human body takes its origin from pre-existent living matter, the spiritual soul is immediately created by God.", "\"In the US, Evangelical Christians have continued to believe in a literal Genesis.", ", members of evangelical Protestant (70%), Mormon (76%) and Jehovah's Witnesses (90%) denominations were the most likely to reject the evolutionary interpretation of the origins of life.Jehovah's Witnesses adhere to a combination of gap creationism and day-age creationism, asserting that scientific evidence about the age of the universe is compatible with the Bible, but that the 'days' after Genesis 1:1 were each thousands of years in length.The historic Christian literal interpretation of creation requires the harmonization of the two creation stories, Genesis 1:1–2:3 and Genesis 2:4–25, for there to be a consistent interpretation.", "They sometimes seek to ensure that their belief is taught in science classes, mainly in American schools.", "Opponents reject the claim that the literalistic biblical view meets the criteria required to be considered scientific.", "Many religious groups teach that God created the Cosmos.", "From the days of the early Christian Church Fathers there were allegorical interpretations of the Book of Genesis as well as literal aspects.Christian Science, a system of thought and practice derived from the writings of Mary Baker Eddy, interprets the Book of Genesis figuratively rather than literally.", "It holds that the material world is an illusion, and consequently not created by God: the only real creation is the spiritual realm, of which the material world is a distorted version.", "Christian Scientists regard the story of the creation in the Book of Genesis as having symbolic rather than literal meaning.", "According to Christian Science, both creationism and evolution are false from an absolute or \"spiritual\" point of view, as they both proceed from a (false) belief in the reality of a material universe.", "However, Christian Scientists do not oppose the teaching of evolution in schools, nor do they demand that alternative accounts be taught: they believe that both material science and literalist theology are concerned with the illusory, mortal and material, rather than the real, immortal and spiritual.", "With regard to material theories of creation, Eddy showed a preference for Darwin's theory of evolution over others.===Hinduism===Hindu creationists claim that species of plants and animals are material forms adopted by pure consciousness which live an endless cycle of births and rebirths.", "Ronald Numbers says that: \"Hindu Creationists have insisted on the antiquity of humans, who they believe appeared fully formed as long, perhaps, as trillions of years ago.\"", "Hindu creationism is a form of old Earth creationism, according to Hindu creationists the universe may even be older than billions of years.", "These views are based on the Vedas, the creation myths of which depict an extreme antiquity of the universe and history of the Earth.In Hindu cosmology, time cyclically repeats general events of creation and destruction, with many \"first man\", each known as Manu, the progenitor of mankind.", "Each Manu successively reigns over a 306.72 million year period known as a , each ending with the destruction of mankind followed by a (period of non-activity) before the next .", "120.53million years have elapsed in the current (current mankind) according to calculations on Hindu units of time.", "The universe is cyclically created at the start and destroyed at the end of a (day of Brahma), lasting for 4.32billion years, which is followed by a (period of dissolution) of equal length.", "1.97billion years have elapsed in the current (current universe).", "The universal elements or building blocks (unmanifest matter) exists for a period known as a , lasting for 311.04trillion years, which is followed by a (period of great dissolution) of equal length.", "155.52trillion years have elapsed in the current .===Islam===Islamic creationism is the belief that the universe (including humanity) was directly created by God as explained in the Quran.", "It usually views the Book of Genesis as a corrupted version of God's message.", "The creation myths in the Quran are vaguer and allow for a wider range of interpretations similar to those in other Abrahamic religions.Islam also has its own school of theistic evolutionism, which holds that mainstream scientific analysis of the origin of the universe is supported by the Quran.", "Some Muslims believe in evolutionary creation, especially among liberal movements within Islam.Writing for ''The Boston Globe'', Drake Bennett noted: \"Without a Book of Genesis to account for... Muslim creationists have little interest in proving that the age of the Earth is measured in the thousands rather than the billions of years, nor do they show much interest in the problem of the dinosaurs.", "And the idea that animals might evolve into other animals also tends to be less controversial, in part because there are passages of the Koran that seem to support it.", "But the issue of whether human beings are the product of evolution is just as fraught among Muslims.\"", "Khalid Anees, president of the Islamic Society of Britain, states that Muslims do not agree that one species can develop from another.Since the 1980s, Turkey has been a site of strong advocacy for creationism, supported by American adherents.There are several verses in the Qur'an which some modern writers have interpreted as being compatible with the expansion of the universe, Big Bang and Big Crunch theories:====Ahmadiyya====The Ahmadiyya movement actively promotes evolutionary theory.", "Ahmadis interpret scripture from the Qur'an to support the concept of macroevolution and give precedence to scientific theories.", "Furthermore, unlike orthodox Muslims, Ahmadis believe that humans have gradually evolved from different species.", "Ahmadis regard Adam as being the first Prophet of Godas opposed to him being the first man on Earth.", "Rather than wholly adopting the theory of natural selection, Ahmadis promote the idea of a \"guided evolution,\" viewing each stage of the evolutionary process as having been selectively woven by God.", "Mirza Tahir Ahmad, Fourth Caliph of the Ahmadiyya Muslim Community has stated in his magnum opus ''Revelation, Rationality, Knowledge & Truth'' (1998) that evolution did occur but only through God being the One who brings it about.", "It does not occur itself, according to the Ahmadiyya Muslim Community.===Judaism===For Orthodox Jews who seek to reconcile discrepancies between science and the creation myths in the Bible, the notion that science and the Bible should even be reconciled through traditional scientific means is questioned.", "To these groups, science is as true as the Torah and if there seems to be a problem, epistemological limits are to blame for apparently irreconcilable points.", "They point to discrepancies between what is expected and what actually is to demonstrate that things are not always as they appear.", "They note that even the root word for 'world' in the Hebrew language, , means 'hidden' ().", "Just as they know from the Torah that God created man and trees and the light on its way from the stars in their observed state, so too can they know that the world was created in its over the six days of Creation that reflects progression to its currently-observed state, with the understanding that physical ways to verify this may eventually be identified.", "This knowledge has been advanced by Rabbi Dovid Gottlieb, former philosophy professor at Johns Hopkins University.", "Relatively old Kabbalistic sources from well before the scientifically apparent age of the universe was first determined are also in close concord with modern scientific estimates of the age of the universe, according to Rabbi Aryeh Kaplan, and based on Sefer Temunah, an early kabbalistic work attributed to the first-century Tanna Nehunya ben HaKanah.", "Many kabbalists accepted the teachings of the Sefer HaTemunah, including the medieval Jewish scholar Nahmanides, his close student Isaac ben Samuel of Acre, and David ben Solomon ibn Abi Zimra.", "Other parallels are derived, among other sources, from Nahmanides, who expounds that there was a Neanderthal-like species with which Adam mated (he did this long before Neanderthals had even been discovered scientifically).", "Reform Judaism does not take the Torah as a literal text, but rather as a symbolic or open-ended work.Some contemporary writers such as Rabbi Gedalyah Nadel have sought to reconcile the discrepancy between the account in the Torah, and scientific findings by arguing that each day referred to in the Bible was not 24 hours, but billions of years long.", "Others claim that the Earth was created a few thousand years ago, but was deliberately made to look as if it was five billion years old, e.g.", "by being created with ready made fossils.", "The best known exponent of this approach being Rabbi Menachem Mendel Schneerson.", "Others state that although the world was physically created in six 24-hour days, the Torah accounts can be interpreted to mean that there was a period of billions of years before the six days of creation." ], [ "Prevalence", "Views on human evolution in various countries 2008Most vocal literalist creationists are from the US, and strict creationist views are much less common in other developed countries.", "According to a study published in ''Science'', a survey of the US, Turkey, Japan and Europe showed that public acceptance of evolution is most prevalent in Iceland, Denmark and Sweden at 80% of the population.", "There seems to be no significant correlation between believing in evolution and understanding evolutionary science.===Australia===A 2009 Nielsen poll showed that 23% of Australians believe \"the biblical account of human origins,\" 42% believe in a \"wholly scientific\" explanation for the origins of life, while 32% believe in an evolutionary process \"guided by God\".A 2013 survey conducted by Auspoll and the Australian Academy of Science found that 80% of Australians believe in evolution (70% believe it is currently occurring, 10% believe in evolution but do not think it is currently occurring), 12% were not sure and 9% stated they do not believe in evolution.===Brazil===A 2011 Ipsos survey found that 47% of responders in Brazil identified themselves as \"creationists and believe that human beings were in fact created by a spiritual force such as the God they believe in and do not believe that the origin of man came from evolving from other species such as apes\".In 2004, IBOPE conducted a poll in Brazil that asked questions about creationism and the teaching of creationism in schools.", "When asked if creationism should be taught in schools, 89% of people said that creationism should be taught in schools.", "When asked if the teaching of creationism should replace the teaching of evolution in schools, 75% of people said that the teaching of creationism should replace the teaching of evolution in schools.===Canada===Big Valley Creation Science Museum in Big Valley, Alberta, CanadaA 2012 survey, by Angus Reid Public Opinion revealed that 61 percent of Canadians believe in evolution.", "The poll asked \"Where did human beings come fromdid we start as singular cells millions of year ago and evolve into our present form, or did God create us in his image 10,000 years ago?", "\"In 2019, a Research Co. poll asked people in Canada if creationism \"should be part of the school curriculum in their province\".", "38% of Canadians said that creationism should be part of the school curriculum, 39% of Canadians said that it should not be part of the school curriculum, and 23% of Canadians were undecided.In 2023, a Research Co. poll found that 21% of Canadians \"believe God created human beings in their present form within the last 10,000 years\".", "The poll also found that \"More than two-in-five Canadians (43%) think creationism should be part of the school curriculum in their province.", "\"===Europe===In Europe, literalist creationism is more widely rejected, though regular opinion polls are not available.", "Most people accept that evolution is the most widely accepted scientific theory as taught in most schools.", "In countries with a Roman Catholic majority, papal acceptance of evolutionary creationism as worthy of study has essentially ended debate on the matter for many people.In the UK, a 2006 poll on the \"origin and development of life\", asked participants to choose between three different perspectives on the origin of life: 22% chose creationism, 17% opted for intelligent design, 48% selected evolutionary theory, and the rest did not know.", "A subsequent 2010 YouGov poll on the correct explanation for the origin of humans found that 9% opted for creationism, 12% intelligent design, 65% evolutionary theory and 13% didn't know.", "The former Archbishop of Canterbury Rowan Williams, head of the worldwide Anglican Communion, views the idea of teaching creationism in schools as a mistake.", "In 2009, an Ipsos Mori survey in the United Kingdom found that 54% of Britons agreed with the view: \"Evolutionary theories should be taught in science lessons in schools together with other possible perspectives, such as intelligent design and creationism.", "\"In Italy, Education Minister Letizia Moratti wanted to retire evolution from the secondary school level; after one week of massive protests, she reversed her opinion.There continues to be scattered and possibly mounting efforts on the part of religious groups throughout Europe to introduce creationism into public education.", "In response, the Parliamentary Assembly of the Council of Europe has released a draft report titled ''The dangers of creationism in education'' on June 8, 2007, reinforced by a further proposal of banning it in schools dated October 4, 2007.Serbia suspended the teaching of evolution for one week in September 2004, under education minister Ljiljana Čolić, only allowing schools to reintroduce evolution into the curriculum if they also taught creationism.", "\"After a deluge of protest from scientists, teachers and opposition parties\" says the BBC report, Čolić's deputy made the statement, \"I have come here to confirm Charles Darwin is still alive\" and announced that the decision was reversed.", "Čolić resigned after the government said that she had caused \"problems that had started to reflect on the work of the entire government.", "\"Poland saw a major controversy over creationism in 2006, when the Deputy Education Minister, Mirosław Orzechowski, denounced evolution as \"one of many lies\" taught in Polish schools.", "His superior, Minister of Education Roman Giertych, has stated that the theory of evolution would continue to be taught in Polish schools, \"as long as most scientists in our country say that it is the right theory.\"", "Giertych's father, Member of the European Parliament Maciej Giertych, has opposed the teaching of evolution and has claimed that dinosaurs and humans co-existed.A June 2015 - July 2016 Pew poll of Eastern European countries found that 56% of people from Armenia say that humans and other living things have \"Existed in present state since the beginning of time\".", "Armenia is followed by 52% from Bosnia, 42% from Moldova, 37% from Lithuania, 34% from Georgia and Ukraine, 33% from Croatia and Romania, 31% from Bulgaria, 29% from Greece and Serbia, 26% from Russia, 25% from Latvia, 23% from Belarus and Poland, 21% from Estonia and Hungary, and 16% from the Czech Republic.===South Africa===A 2011 Ipsos survey found that 56% of responders in South Africa identified themselves as \"creationists and believe that human beings were in fact created by a spiritual force such as the God they believe in and do not believe that the origin of man came from evolving from other species such as apes\".===South Korea===In 2009, an EBS survey in South Korea found that 63% of people believed that creation and evolution should both be taught in schools simultaneously.===United States===The Ark Encounter theme park in Williamstown, Kentucky, United StatesGlendive Dinosaur and Fossil Museum in Glendive, Montana, United StatesAnti-evolution car in Athens, Georgia A 2017 poll by Pew Research found that 62% of Americans believe humans have evolved over time and 34% of Americans believe humans and other living things have existed in their present form since the beginning of time.", "A 2019 Gallup creationism survey found that 40% of adults in the United States inclined to the view that \"God created humans in their present form at one time within the last 10,000 years\" when asked for their views on the origin and development of human beings.According to a 2014 Gallup poll, about 42% of Americans believe that \"God created human beings pretty much in their present form at one time within the last 10,000 years or so.\"", "Another 31% believe that \"human beings have developed over millions of years from less advanced forms of life, but God guided this process,\"and 19% believe that \"human beings have developed over millions of years from less advanced forms of life, but God had no part in this process.", "\"Belief in creationism is inversely correlated to education; of those with postgraduate degrees, 74% accept evolution.", "In 1987, ''Newsweek'' reported: \"By one count there are some 700 scientists with respectable academic credentials (out of a total of 480,000 U.S. earth and life scientists) who give credence to creation-science, the general theory that complex life forms did not evolve but appeared 'abruptly.", "'\"A 2000 poll for People for the American Way found 70% of the US public felt that evolution was compatible with a belief in God.According to a study published in ''Science'', between 1985 and 2005 the number of adult North Americans who accept evolution declined from 45% to 40%, the number of adults who reject evolution declined from 48% to 39% and the number of people who were unsure increased from 7% to 21%.", "Besides the US the study also compared data from 32 European countries, Turkey, and Japan.", "The only country where acceptance of evolution was lower than in the US was Turkey (25%).According to a 2011 Fox News poll, 45% of Americans believe in creationism, down from 50% in a similar poll in 1999.21% believe in 'the theory of evolution as outlined by Darwin and other scientists' (up from 15% in 1999), and 27% answered that both are true (up from 26% in 1999).In September 2012, educator and television personality Bill Nye spoke with the Associated Press and aired his fears about acceptance of creationism, believing that teaching children that creationism is the only true answer without letting them understand the way science works will prevent any future innovation in the world of science.", "In February 2014, Nye defended evolution in the classroom in a debate with creationist Ken Ham on the topic of whether creation is a viable model of origins in today's modern, scientific era.====Education controversies====Darwin fish In the US, creationism has become centered in the political controversy over creation and evolution in public education, and whether teaching creationism in science classes conflicts with the separation of church and state.", "Currently, the controversy comes in the form of whether advocates of the intelligent design movement who wish to \"Teach the Controversy\" in science classes have conflated science with religion.People for the American Way polled 1500 North Americans about the teaching of evolution and creationism in November and December 1999.They found that most North Americans were not familiar with creationism, and most North Americans had heard of evolution, but many did not fully understand the basics of the theory.", "The main findings were:In such political contexts, creationists argue that their particular religiously based origin belief is superior to those of other belief systems, in particular those made through secular or scientific rationale.", "Political creationists are opposed by many individuals and organizations who have made detailed critiques and given testimony in various court cases that the alternatives to scientific reasoning offered by creationists are opposed by the consensus of the scientific community." ], [ "Criticism", "===Christian criticism===Most Christians disagree with the teaching of creationism as an alternative to evolution in schools.", "Several religious organizations, among them the Catholic Church, hold that their faith does not conflict with the scientific consensus regarding evolution.", "The Clergy Letter Project, which has collected more than 13,000 signatures, is an \"endeavor designed to demonstrate that religion and science can be compatible.", "\"In his 2002 article \"Intelligent Design as a Theological Problem\", George Murphy argues against the view that life on Earth, in all its forms, is direct evidence of God's act of creation (Murphy quotes Phillip E. Johnson's claim that he is speaking \"of a God who acted openly and left his fingerprints on all the evidence.\").", "Murphy argues that this view of God is incompatible with the Christian understanding of God as \"the one revealed in the cross and resurrection of Christ.\"", "The basis of this theology is Isaiah 45:15, \"Verily thou art a God that hidest thyself, O God of Israel, the Saviour.", "\"Murphy observes that the execution of a Jewish carpenter by Roman authorities is in and of itself an ordinary event and did not require divine action.", "On the contrary, for the crucifixion to occur, God had to limit or \"empty\" himself.", "It was for this reason that Paul the Apostle wrote, in Philippians 2:5-8:Let this mind be in you, which was also in Christ Jesus: Who, being in the form of God, thought it not robbery to be equal with God: But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men: And being found in fashion as a man, he humbled himself, and became obedient unto death, even the death of the cross.Murphy concludes that,Just as the Son of God limited himself by taking human form and dying on a cross, God limits divine action in the world to be in accord with rational laws which God has chosen.", "This enables us to understand the world on its own terms, but it also means that natural processes hide God from scientific observation.For Murphy, a theology of the cross requires that Christians accept a ''methodological'' naturalism, meaning that one cannot invoke God to explain natural phenomena, while recognizing that such acceptance does not require one to accept a ''metaphysical'' naturalism, which proposes that nature is all that there is.The Jesuit priest George Coyne has stated that it is \"unfortunate that, especially here in America, creationism has come to mean...some literal interpretation of Genesis.\"", "He argues that \"...Judaic-Christian faith is radically creationist, but in a totally different sense.", "It is rooted in belief that everything depends on God, or better, all is a gift from God.", "\"===Teaching of creationism===Other Christians have expressed qualms about teaching creationism.", "In March 2006, then Archbishop of Canterbury Rowan Williams, the leader of the world's Anglicans, stated his discomfort about teaching creationism, saying that creationism was \"a kind of category mistake, as if the Bible were a theory like other theories.\"", "He also said: \"My worry is creationism can end up reducing the doctrine of creation rather than enhancing it.\"", "The views of the Episcopal Churcha major American-based branch of the Anglican Communionon teaching creationism resemble those of Williams.The National Science Teachers Association is opposed to teaching creationism as a science, as is the Association for Science Teacher Education, the National Association of Biology Teachers, the American Anthropological Association, the American Geosciences Institute, the Geological Society of America, the American Geophysical Union, and numerous other professional teaching and scientific societies.In April 2010, the American Academy of Religion issued ''Guidelines for Teaching About Religion in K‐12 Public Schools in the United States'', which included guidance that creation science or intelligent design should not be taught in science classes, as \"Creation science and intelligent design represent worldviews that fall outside of the realm of science that is defined as (and limited to) a method of inquiry based on gathering observable and measurable evidence subject to specific principles of reasoning.\"", "However, they, as well as other \"worldviews that focus on speculation regarding the origins of life represent another important and relevant form of human inquiry that is appropriately studied in literature or social sciences courses.", "Such study, however, must include a diversity of worldviews representing a variety of religious and philosophical perspectives and must avoid privileging one view as more legitimate than others.", "\"Randy Moore and Sehoya Cotner, from the biology program at the University of Minnesota, reflect on the relevance of teaching creationism in the article \"The Creationist Down the Hall: Does It Matter When Teachers Teach Creationism?", "\", in which they write: \"Despite decades of science education reform, numerous legal decisions declaring the teaching of creationism in public-school science classes to be unconstitutional, overwhelming evidence supporting evolution, and the many denunciations of creationism as nonscientific by professional scientific societies, creationism remains popular throughout the United States.", "\"===Scientific criticism===Science is a system of knowledge based on observation, empirical evidence, and the development of theories that yield testable explanations and predictions of natural phenomena.", "By contrast, creationism is often based on literal interpretations of the narratives of particular religious texts.", "Creationist beliefs involve purported forces that lie outside of nature, such as supernatural intervention, and often do not allow predictions at all.", "Therefore, these can neither be confirmed nor disproved by scientists.", "However, many creationist beliefs can be framed as testable predictions about phenomena such as the age of the Earth, its geological history and the origins, distributions and relationships of living organisms found on it.", "Early science incorporated elements of these beliefs, but as science developed these beliefs were gradually falsified and were replaced with understandings based on accumulated and reproducible evidence that often allows the accurate prediction of future results.Some scientists, such as Stephen Jay Gould, consider science and religion to be two compatible and complementary fields, with authorities in distinct areas of human experience, so-called non-overlapping magisteria.", "This view is also held by many theologians, who believe that ultimate origins and meaning are addressed by religion, but favor verifiable scientific explanations of natural phenomena over those of creationist beliefs.", "Other scientists, such as Richard Dawkins, reject the non-overlapping magisteria and argue that, in disproving literal interpretations of creationists, the scientific method also undermines religious texts as a source of truth.", "Irrespective of this diversity in viewpoints, since creationist beliefs are not supported by empirical evidence, the scientific consensus is that any attempt to teach creationism as science should be rejected." ], [ "Organizations", ";Creationism (in general)* American Scientific Affiliation* Christians in Science;Young Earth creationism* Answers in Genesis, a group promoting young Earth creationism* Creation Ministries International, an organisation promoting biblical creation* Creation Research Society* Institute for Creation Research* The Way of the Master;Old Earth creationism* Old Earth Ministries (OEM), formerly Answers In Creation (AIC), led by Greg Neyman* Reasons to Believe, led by Hugh Ross;Intelligent design* Access Research Network* Centre for Intelligent Design* Center for Science and Culture, a subsidiary of the Discovery Institute;Evolutionary creationism* BioLogos Foundation" ], [ "See also", "* Biblical inerrancy* Biogenesis* Dangers of creationism in education* Evolution of complexity* Flying Spaghetti Monster* History of creationism* Religious cosmology" ], [ "Notes" ], [ "References", "===Citations======Works cited===* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * \"Presented as a Paleontological Society short course at the annual meeting of the Geological Society of America, Denver, Colorado, October 24, 1999.", "\"* * * * * * *" ], [ "Further reading", "* * * * * * * * * * *" ], [ "External links", "* \"Creationism\" at the Stanford Encyclopedia of Philosophy by Michael Ruse* \"How Creationism Works\" at HowStuffWorks by Julia Layton* \"TIMELINE: Evolution, Creationism and Intelligent Design\"Focuses on major historical and recent events in the scientific and political debate*   by Warren D. Allmon, Director of the Museum of the Earth* \"What is creationism?\"", "at talk.origins by Mark Isaak* \"The Creation/Evolution Continuum\" by Eugenie Scott* \"15 Answers to Creationist Nonsense\" by John Rennie, editor in chief of ''Scientific American'' magazine* \" Race, Evolution and the Science of Human Origins\" by Allison Hopper, ''Scientific American'' (July 5, 2021).", "* Human Timeline (Interactive)Smithsonian, National Museum of Natural History (August 2016)" ] ]

[ [ "History of Chad" ], [ "Introduction", "'''Chad''' (; ), officially the '''Republic of Chad''', is a landlocked country in Central Africa.", "It borders Libya to the north, Sudan to the east, the Central African Republic to the south, Cameroon and Nigeria to the southwest, and Niger to the west.", "Due to its distance from the sea and its largely desert climate, the country is sometimes referred to as the \"Dead Heart of Africa\"." ], [ "Prehistory", "Location of ''Sahelanthropus tchadensis'' find in 2002.The territory now known as Chad possesses some of the richest archaeological sites in Africa.", "A hominid skull was found by Michel Brunet, that is more than 7 million years old, the oldest discovered anywhere in the world; it has been given the name Sahelanthropus tchadensis.", "In 1996 Michel Brunet had unearthed a hominid jaw which he named Australopithecus bahrelghazali, and unofficially dubbed Abel.", "It was dated using Beryllium based Radiometric dating as living circa.", "3.6 million years ago.During the 7th millennium BC, the northern half of Chad was part of a broad expanse of land, stretching from the Indus River in the east to the Atlantic Ocean in the west, in which ecological conditions favored early human settlement.", "Rock art of the \"Round Head\" style, found in the Ennedi region, has been dated to before the 7th millennium BC and, because of the tools with which the rocks were carved and the scenes they depict, may represent the oldest evidence in the Sahara of Neolithic industries.", "Many of the pottery-making and Neolithic activities in Ennedi date back further than any of those of the Nile Valley to the east.In the prehistoric period, Chad was much wetter than it is today, as evidenced by large game animals depicted in rock paintings in the Tibesti and Borkou regions.Recent linguistic research suggests that all of Africa's major language groupings south of the Sahara Desert (except Khoisan, which is not considered a valid genetic grouping anyway), i.e.", "the Afro-Asiatic, Nilo-Saharan and Niger–Congo phyla, originated in prehistoric times in a narrow band between Lake Chad and the Nile Valley.", "The origins of Chad's peoples, however, remain unclear.", "Several of the proven archaeological sites have been only partially studied, and other sites of great potential have yet to be mapped." ], [ "Era of Empires (AD 900&ndash;1900)", "At the end of the 1st millennium AD, the formation of states began across central Chad in the sahelian zone between the desert and the savanna.", "For almost the next 1,000 years, these states, their relations with each other, and their effects on the peoples who lived in stateless societies along their peripheries dominated Chad's political history.", "Recent research suggests that indigenous Africans founded of these states, not migrating Arabic-speaking groups, as was believed previously.", "Nonetheless, immigrants, Arabic-speaking or otherwise, played a significant role, along with Islam, in the formation and early evolution of these states.Most states began as kingdoms, in which the king was considered divine and endowed with temporal and spiritual powers.", "All states were militaristic (or they did not survive long), but none was able to expand far into southern Chad, where forests and the tsetse fly complicated the use of cavalry.", "Control over the trans-Saharan trade routes that passed through the region formed the economic basis of these kingdoms.", "Although many states rose and fell, the most important and durable of the empires were Kanem–Bornu, Baguirmi, and Ouaddai, according to most written sources (mainly court chronicles and writings of Arab traders and travelers).", "Chad - ERA OF EMPIRES, A.D. 900–1900===Kanem–Bornu===The Kanem Empire originated in the 9th century AD to the northeast of Lake Chad.", "Historians agree that the leaders of the new state were ancestors of the Kanembu people.", "Toward the end of the 11th century the Sayfawa king (or ''mai'', the title of the Sayfawa rulers) Hummay, converted to Islam.", "In the following century the Sayfawa rulers expanded southward into Kanem, where was to rise their first capital, Njimi.", "Kanem's expansion peaked during the long and energetic reign of Mai Dunama Dabbalemi (c. 1221–1259).Group of Kanem-Bu warriorsBy the end of the 14th century, internal struggles and external attacks had torn Kanem apart.", "Finally, around 1396 the Bulala invaders forced ''Mai'' Umar Idrismi to abandon Njimi and move the Kanembu people to Bornu on the western edge of Lake Chad.", "Over time, the intermarriage of the Kanembu and Bornu peoples created a new people and language, the Kanuri, and founded a new capital, Ngazargamu.Kanem–Bornu peaked during the reign of the outstanding statesman ''Mai'' Idris Aluma (c. 1571–1603).", "Aluma is remembered for his military skills, administrative reforms, and Islamic piety.", "The administrative reforms and military brilliance of Aluma sustained the empire until the mid-17th century, when its power began to fade.", "By the early 19th century, Kanem–Bornu was clearly an empire in decline, and in 1808 Fulani warriors conquered Ngazargamu.", "Bornu survived, but the Sayfawa dynasty ended in 1846 and the Empire itself fell in 1893.===Baguirmi and Ouaddai===The Kingdom of Baguirmi, located southeast of Kanem-Bornu, was founded in the late 15th or early 16th century, and adopted Islam in the reign of Abdullah IV (1568–98).", "Baguirmi was in a tributary relationship with Kanem–Bornu at various points in the 17th and 18th centuries, then to Ouaddai in the 19th century.", "In 1893, Baguirmi sultan Abd ar Rahman Gwaranga surrendered the territory to France, and it became a French protectorate.The Ouaddai Kingdom, west of Kanem–Bornu, was established in the early 16th century by Tunjur rulers.", "In the 1630s, Abd al Karim invaded and established an Islamic sultanate.", "Among its most impactful rulers for the next three centuries were Muhammad Sabun, who controlled a new trade route to the north and established a currency during the early 19th century, and Muhammad Sharif, whose military campaigns in the mid 19th century fended off an assimilation attempt from Darfur, conquered Baguirmi, and successfully resisted French colonization.", "However, Ouaddai lost its independence to France after a war from 1909 to 1912." ], [ "Colonialism (1900&ndash;1940)", "Death of Commander Lamy of France, 1900The French first invaded Chad in 1891, establishing their authority through military expeditions primarily against the Muslim kingdoms.", "The decisive colonial battle for Chad was fought on April 22, 1900 at Battle of Kousséri between forces of French Major Amédée-François Lamy and forces of the Sudanese warlord Rabih az-Zubayr.", "Both leaders were killed in the battle.In 1905, administrative responsibility for Chad was placed under a governor-general stationed at Brazzaville, capital of French Equatorial Africa (FEA).", "Chad did not have a separate colonial status until 1920, when it was placed under a lieutenant-governor stationed in Fort-Lamy (today N'Djamena).Two fundamental themes dominated Chad's colonial experience with the French: an absence of policies designed to unify the territory and an exceptionally slow pace of modernization.", "In the French scale of priorities, the colony of Chad ranked near the bottom, and the French came to perceive Chad primarily as a source of raw cotton and untrained labour to be used in the more productive colonies to the south.Throughout the colonial period, large areas of Chad were never governed effectively: in the huge BET Prefecture, the handful of French military administrators usually left the people alone, and in central Chad, French rule was only slightly more substantive.", "Truly speaking, France managed to govern effectively only the south." ], [ "Decolonization (1940&ndash;1960)", "Félix Éboué in a contemporary World War II cartoonDuring World War II, Chad was the first French colony to rejoin the Allies (August 26, 1940), after the defeat of France by Germany.", "Under the administration of Félix Éboué, France's first black colonial governor, a military column, commanded by Colonel Philippe Leclerc de Hauteclocque, and including two battalions of Sara troops, moved north from N'Djamena (then Fort Lamy) to engage Axis forces in Libya, where, in partnership with the British Army's Long Range Desert Group, they captured Kufra.", "On 21 January 1942, N'Djamena was bombed by a German aircraft.After the war ended, local parties started to develop in Chad.", "The first to be born was the radical Chadian Progressive Party (PPT) in February 1947, initially headed by Panamanian born Gabriel Lisette, but from 1959 headed by François Tombalbaye.", "The more conservative Chadian Democratic Union (UDT) was founded in November 1947 and represented French commercial interests and a bloc of traditional leaders composed primarily of Muslim and Ouaddaïan nobility.", "The confrontation between the PPT and UDT was more than simply ideological; it represented different regional identities, with the PPT representing the Christian and animist south and the UDT the Islamic north.The PPT won the May 1957 pre-independence elections thanks to a greatly expanded franchise, and Lisette led the government of the Territorial Assembly until he lost a confidence vote on 11 February 1959.After a referendum on territorial autonomy on 28 September 1958, French Equatorial Africa was dissolved, and its four constituent states – Gabon, Congo (Brazzaville), the Central African Republic, and Chad became autonomous members of the French Community from 28 November 1958.Following Lisette's fall in February 1959 the opposition leaders Gontchome Sahoulba and Ahmed Koulamallah could not form a stable government, so the PPT was again asked to form an administration - which it did under the leadership of François Tombalbaye on 26 March 1959.On 12 July 1960 France agreed to Chad becoming fully independent.", "On 11 August 1960, Chad became an independent country and François Tombalbaye became its first president." ], [ "The Tombalbaye era (1960&ndash;1975)", "One of the most prominent aspects of Tombalbaye's rule to prove itself was his authoritarianism and distrust of democracy.", "Already in January 1962 he banned all political parties except his own PPT, and started immediately concentrating all power in his own hands.", "His treatment of opponents, real or imagined, was extremely harsh, filling the prisons with thousands of political prisoners.What was even worse was his constant discrimination against the central and northern regions of Chad, where the southern Chadian administrators came to be perceived as arrogant and incompetent.", "This resentment at last exploded in a tax revolt on September 2, 1965 in the Guéra Prefecture, causing 500 deaths.", "The year after saw the birth in Sudan of the National Liberation Front of Chad (FROLINAT), created to militarily oust Tombalbaye and the Southern dominance.", "It was the start of a bloody civil war.Tombalbaye resorted to calling in French troops; while moderately successful, they were not fully able to quell the insurgency.", "Proving more fortunate was his choice to break with the French and seek friendly ties with Libyan Brotherly Leader Gaddafi, taking away the rebels' principal source of supplies.But while he had reported some success against the rebels, Tombalbaye started behaving more and more irrationally and brutally, continuously eroding his consensus among the southern elites, which dominated all key positions in the army, the civil service and the ruling party.", "As a consequence on April 13, 1975, several units of N'Djamena's gendarmerie killed Tombalbaye during a coup." ], [ "Military rule (1975&ndash;1978)", "The coup d'état that terminated Tombalbaye's government received an enthusiastic response in N'Djamena.", "The southerner General Félix Malloum emerged early as the chairman of the new ''junta''.The new military leaders were unable to retain for long the popularity that they had gained through their overthrow of Tombalbaye.", "Malloum proved himself unable to cope with the FROLINAT and at the end decided his only chance was in coopting some of the rebels: in 1978 he allied himself with the insurgent leader Hissène Habré, who entered the government as prime minister." ], [ "Civil war (1979-1982)", "Internal dissent within the government led Prime Minister Habré to send his forces against Malloum's national army in the capital in February 1979.Malloum was ousted from the presidency, but the resulting civil war amongst the 11 emergent factions was so widespread that it rendered the central government largely irrelevant.", "At that point, other African governments decided to intervene.A series of four international conferences held first under Nigerian and then Organization of African Unity (OAU) sponsorship attempted to bring the Chadian factions together.", "At the fourth conference, held in Lagos, Nigeria, in August 1979, the Lagos Accord was signed.", "This accord established a transitional government pending national elections.", "In November 1979, the Transitional Government of National Unity (GUNT) was created with a mandate to govern for 18 months.", "Goukouni Oueddei, a northerner, was named president; Colonel Kamougué, a southerner, Vice President; and Habré, Minister of Defense.", "This coalition proved fragile; in January 1980, fighting broke out again between Goukouni's and Habré's forces.", "With assistance from Libya, Goukouni regained control of the capital and other urban centers by year's end.", "However, Goukouni's January 1981 statement that Chad and Libya had agreed to work for the realization of complete unity between the two countries generated intense international pressure and Goukouni's subsequent call for the complete withdrawal of external forces." ], [ "The Habré era (1982&ndash;1990)", "Libya's partial withdrawal to the Aozou Strip in northern Chad cleared the way for Habré's forces to enter N’Djamena in June.", "French troops and an OAU peacekeeping force of 3,500 Nigerian, Senegalese, and Zairian troops (partially funded by the United States) remained neutral during the conflict.The Aozou Strip (dark green), claimed and occupied by Libya between 1976 and 1987, and territories held by Libyan-backed GUNT-forces (light green)Habré continued to face armed opposition on various fronts, and was brutal in his repression of suspected opponents, massacring and torturing many during his rule.", "In the summer of 1983, GUNT forces launched an offensive against government positions in northern and eastern Chad with heavy Libyan support.", "In response to Libya's direct intervention, French and Zairian forces intervened to defend Habré, pushing Libyan and rebel forces north of the 16th parallel.", "In September 1984, the French and the Libyan governments announced an agreement for the mutual withdrawal of their forces from Chad.", "By the end of the year, all French and Zairian troops were withdrawn.", "Libya did not honor the withdrawal accord, and its forces continued to occupy the northern third of Chad.Rebel commando groups (Codos) in southern Chad were broken up by government massacres in 1984.In 1985 Habré briefly reconciled with some of his opponents, including the Democratic Front of Chad (FDT) and the Coordinating Action Committee of the Democratic Revolutionary Council.", "Goukouni also began to rally toward Habré, and with his support Habré successfully expelled Libyan forces from most of Chadian territory.", "A cease-fire between Chad and Libya held from 1987 to 1988, and negotiations over the next several years led to the 1994 International Court of Justice decision granting Chad sovereignty over the Aouzou strip, effectively ending Libyan occupation." ], [ "The Idriss Déby era (1990–2021)", "===Rise to power===However, rivalry between Hadjerai, Zaghawa and Gorane groups within the government grew in the late 1980s.", "In April 1989, Idriss Déby, one of Habré's leading generals and a Zaghawa, defected and fled to Darfur in Sudan, from which he mounted a Zaghawa-supported series of attacks on Habré (a Gorane).", "In December 1990, with Libyan assistance and no opposition from French troops stationed in Chad, Déby's forces successfully marched on N’Djamena.", "After 3 months of provisional government, Déby's Patriotic Salvation Movement (MPS) approved a national charter on February 28, 1991, with Déby as president.During the next two years, Déby faced at least two coup attempts.", "Government forces clashed violently with rebel forces, including the Movement for Democracy and Development, MDD, National Revival Committee for Peace and Democracy (CSNPD), Chadian National Front (FNT) and the Western Armed Forces (FAO), near Lake Chad and in southern regions of the country.", "Earlier French demands for the country to hold a National Conference resulted in the gathering of 750 delegates representing political parties (which were legalized in 1992), the government, trade unions and the army to discuss the creation of a pluralist democratic regime.However, unrest continued, sparked in part by large-scale killings of civilians in southern Chad.", "The CSNPD, led by Kette Moise and other southern groups entered into a peace agreement with government forces in 1994, which later broke down.", "Two new groups, the Armed Forces for a Federal Republic (FARF) led by former Kette ally Laokein Barde and the Democratic Front for Renewal (FDR), and a reformulated MDD clashed with government forces from 1994 to 1995.===Multiparty elections===Talks with political opponents in early 1996 did not go well, but Déby announced his intent to hold presidential elections in June.", "Déby won the country's first multi-party presidential elections with support in the second round from opposition leader Kebzabo, defeating General Kamougue (leader of the 1975 coup against Tombalbaye).", "Déby's MPS party won 63 of 125 seats in the January 1997 legislative elections.", "International observers noted numerous serious irregularities in presidential and legislative election proceedings.By mid-1997 the government signed peace deals with FARF and the MDD leadership and succeeded in cutting off the groups from their rear bases in the Central African Republic and Cameroon.", "Agreements also were struck with rebels from the National Front of Chad (FNT) and Movement for Social Justice and Democracy in October 1997.However, peace was short-lived, as FARF rebels clashed with government soldiers, finally surrendering to government forces in May 1998.Barde was killed in the fighting, as were hundreds of other southerners, most civilians.Since October 1998, Chadian Movement for Justice and Democracy (MDJT) rebels, led by Youssuf Togoimi until his death in September 2002, have skirmished with government troops in the Tibesti region, resulting in hundreds of civilian, government, and rebel casualties, but little ground won or lost.", "No active armed opposition has emerged in other parts of Chad, although Kette Moise, following senior postings at the Ministry of Interior, mounted a smallscale local operation near Moundou which was quickly and violently suppressed by government forces in late 2000.Déby, in the mid-1990s, gradually restored basic functions of government and entered into agreements with the World Bank and IMF to carry out substantial economic reforms.", "Oil exploitation in the southern Doba region began in June 2000, with World Bank Board approval to finance a small portion of a project, the Chad-Cameroon Petroleum Development Project, aimed at transport of Chadian crude through a 1000-km buried pipeline through Cameroon to the Gulf of Guinea.", "The project established unique mechanisms for World Bank, private sector, government, and civil society collaboration to guarantee that future oil revenues benefit local populations and result in poverty alleviation.", "Success of the project depended on multiple monitoring efforts to ensure that all parties keep their commitments.", "These \"unique\" mechanisms for monitoring and revenue management have faced intense criticism from the beginning.", "Debt relief was accorded to Chad in May 2001.Déby won a flawed 63% first-round victory in May 2001 presidential elections after legislative elections were postponed until spring 2002.Having accused the government of fraud, six opposition leaders were arrested (twice) and one opposition party activist was killed following the announcement of election results.", "However, despite claims of government corruption, favoritism of Zaghawas, and abuses by the security forces, opposition party and labor union calls for general strikes and more active demonstrations against the government have been unsuccessful.", "Despite movement toward democratic reform, power remains in the hands of a northern ethnic oligarchy.In 2003, Chad began receiving refugees from the Darfur region of western Sudan.", "More than 200,000 refugees fled the fighting between two rebel groups and government-supported militias known as Janjaweed.", "A number of border incidents led to the Chadian-Sudanese War.===Oil producing and military improvement===Chad become an oil producer in 2003.In order to avoid resource curse and corruption, elaborate plans sponsored by World Bank were made.", "This plan ensured transparency in payments, as well as that 80% of money from oil exports would be spent on five priority development sectors, two most important of these being: education and healthcare.", "However money started getting diverted towards the military even before the civil war broke out.", "In 2006 when the civil war escalated, Chad abandoned previous economic plans sponsored by World Bank and added \"national security\" as priority development sector, money from this sector was used to improve the military.", "During the civil war, more than 600 million dollars were used to buy fighter jets, attack helicopters, and armored personnel carriers.Chad earned between 10 and 11 billion dollars from oil production, and estimated 4 billion dollars were invested in the army.===War in the East===Hot spots in the civil war.The war started on December 23, 2005, when the government of Chad declared a state of war with Sudan and called for the citizens of Chad to mobilize themselves against the \"common enemy,\" which the Chadian government sees as the Rally for Democracy and Liberty (RDL) militants, Chadian rebels, backed by the Sudanese government, and Sudanese militiamen.", "Militants have attacked villages and towns in eastern Chad, stealing cattle, murdering citizens, and burning houses.", "Over 200,000 refugees from the Darfur region of northwestern Sudan currently claim asylum in eastern Chad.", "Chadian president Idriss Déby accuses Sudanese President Omar Hasan Ahmad al-Bashir of trying to \"destabilize our country, to drive our people into misery, to create disorder and export the war from Darfur to Chad.", "\"An attack on the Chadian town of Adre near the Sudanese border led to the deaths of either one hundred rebels, as every news source other than CNN has reported, or three hundred rebels.", "The Sudanese government was blamed for the attack, which was the second in the region in three days, but Sudanese foreign ministry spokesman Jamal Mohammed Ibrahim denies any Sudanese involvement, \"We are not for any escalation with Chad.", "We technically deny involvement in Chadian internal affairs.\"", "This attack was the final straw that led to the declaration of war by Chad and the alleged deployment of the Chadian airforce into Sudanese airspace, which the Chadian government denies.An attack on N'Djamena was defeated on April 13, 2006 in the Battle of N'Djamena.", "The President on national radio stated that the situation was under control, but residents, diplomats and journalists reportedly heard shots of weapons fire.On November 25, 2006, rebels captured the eastern town of Abeche, capital of the Ouaddaï Region and center for humanitarian aid to the Darfur region in Sudan.", "On the same day, a separate rebel group Rally of Democratic Forces had captured Biltine.", "On November 26, 2006, the Chadian government claimed to have recaptured both towns, although rebels still claimed control of Biltine.", "Government buildings and humanitarian aid offices in Abeche were said to have been looted.", "The Chadian government denied a warning issued by the French Embassy in N'Djamena that a group of rebels was making its way through the Batha Prefecture in central Chad.", "Chad insists that both rebel groups are supported by the Sudanese government.===International orphanage scandal===Nearly 100 children at the center of an international scandal that left them stranded at an orphanage in remote eastern Chad returned home after nearly five months March 14, 2008.The 97 children were taken from their homes in October 2007 by a then-obscure French charity, Zoé's Ark, which claimed they were orphans from Sudan's war-torn Darfur region.===Rebel attack on Ndjamena===On Friday, February 1, 2008, rebels, an opposition alliance of leaders Mahamat Nouri, a former defense minister, and Timane Erdimi, a nephew of Idriss Déby who was his chief of staff, attacked the Chadian capital of Ndjamena - even surrounding the Presidential Palace.", "But Idris Deby with government troops fought back.", "French forces flew in ammunition for Chadian government troops but took no active part in the fighting.", "UN has said that up to 20,000 people left the region, taking refuge in nearby Cameroon and Nigeria.", "Hundreds of people were killed, mostly civilians.", "The rebels accuse Deby of corruption and embezzling millions in oil revenue.", "While many Chadians may share that assessment, the uprising appears to be a power struggle within the elite that has long controlled Chad.", "The French government believes that the opposition has regrouped east of the capital.", "Déby has blamed Sudan for the current unrest in Chad.===Regional interventionism===During the Déby era, Chad intervened in conflicts in Mali, Central African Republic, Niger and Nigeria.In 2013, Chad sent 2000 men from its military to help France in Operation Serval during the Mali War.", "Later in the same year Chad sent 850 troops to Central African Republic to help peacekeeping operation MISCA, those troops withdrew in April 2014 after allegations of human rights violations.During the Boko Haram insurgency, Chad multiple times sent troops to assist the fight against Boko Haram in Niger and Nigeria.In August 2018, rebel fighters of the Military Command Council for the Salvation of the Republic (CCMSR) attacked government forces in northern Chad.", "Chad experienced threats from jihadists fleeing the Libyan conflict.", "Chad had been an ally of the West in the fight against Islamist militants in West Africa.In January 2019, after 47 years, Chad restored diplomatic relations with Israel.", "It was announced during a visit to N’Djamena by Israeli Prime Minister Benjamin Netanyahu." ], [ "After Idriss Déby (2021–present)", "In April 2021, Chad's army announced that President Idriss Déby had died of his injuries following clashes with rebels in the north of the country.", "Idriss Deby ruled the country for more than 30 years since 1990.It was also announced that a military council led by Déby's son, Mahamat Idriss Déby a 37-year-old four star general, will govern for the next 18 months." ], [ "See also", "*2010 Sahel famine*History of Africa*List of heads of government of Chad*List of heads of state of Chad*List of human evolution fossils*Politics of Chad*Neolithic Subpluvial*" ], [ "Further reading", "*Gibbons, Ann.", "''The First Human : The Race to Discover our Earliest Ancestor''.", "Anchor Books (2007)." ], [ "References" ], [ "External links", "* The Library of Congress - A Country Study: Chad" ] ]

[ [ "Geography of Chad" ], [ "Introduction", "A map of ChadLocation of Chad'''Chad''' is one of the 47 landlocked countries in the world and is located in North Central Africa, measuring , nearly twice the size of France and slightly more than three times the size of California.", "Most of its ethnically and linguistically diverse population lives in the south, with densities ranging from 54 persons per square kilometer in the Logone River basin to 0.1 persons in the northern B.E.T.", "(Borkou-Ennedi-Tibesti) desert region, which itself is larger than France.", "The capital city of N'Djaména, situated at the confluence of the Chari and Logone Rivers, is cosmopolitan in nature, with a current population in excess of 700,000 people.Chad has four climatic zones.", "The northernmost Saharan zone averages less than of rainfall annually.", "The sparse human population is largely nomadic, with some livestock, mostly small ruminants and camels.", "The central Sahelian zone receives between rainfall and has vegetation ranging from grass/shrub steppe to thorny, open savanna.", "The southern zone, often referred to as the Sudan zone, receives between , with woodland savanna and deciduous forests for vegetation.", "Rainfall in the Guinea zone, located in Chad's southwestern tip, ranges between .The country's topography is generally flat, with the elevation gradually rising as one moves north and east away from Lake Chad.", "The highest point in Chad is Emi Koussi, a mountain that rises in the northern Tibesti Mountains.", "The Ennedi Plateau and the Ouaddaï highlands in the east complete the image of a gradually sloping basin, which descends towards Lake Chad.", "There are also central highlands in the Guera region rising to .Lake Chad is the second largest lake in west Africa and is one of the most important wetlands on the continent.", "Home to 120 species of fish and at least that many species of birds, the lake has shrunk dramatically in the last four decades due to increased water usage from an expanding population and low rainfall.", "Bordered by Chad, Niger, Nigeria, and Cameroon, Lake Chad currently covers only 1350 square kilometers, down from 25,000 square kilometers in 1963.The Chari and Logone Rivers, both of which originate in the Central African Republic and flow northward, provide most of the surface water entering Lake Chad.", "Chad is also next to Niger." ], [ "Geographical placement", "A satellite image of Chad.A satellite image of Chad.A topographic map of Chad.Located in north-central Africa, Chad stretches for about 1,800 kilometers from its northernmost point to its southern boundary.", "Except in the far northwest and south, where its borders converge, Chad's average width is about 800 kilometers.", "Its area of 1,284,000 square kilometers is roughly equal to the combined areas of Idaho, Wyoming, Utah, Nevada, and Arizona.", "Chad's neighbors include Libya to the north, Niger and Nigeria to the west, Sudan to the east, Central African Republic to the south, and Cameroon to the southwest.Chad exhibits two striking geographical characteristics.", "First, the country is landlocked.", "N'Djamena, the capital, is located more than 1,100 kilometers northeast of the Atlantic Ocean; Abéché, a major city in the east, lies 2,650 kilometers from the Red Sea; and Faya-Largeau, a much smaller but strategically important center in the north, is in the middle of the Sahara Desert, 1,550 kilometers from the Mediterranean Sea.", "These vast distances from the sea have had a profound impact on Chad's historical and contemporary development.The second noteworthy characteristic is that the country borders on very different parts of the African continent: North Africa, with its Islamic culture and economic orientation toward the Mediterranean Basin; and West Africa, with its diverse religions and cultures and its history of highly developed states and regional economies.Chad also borders Northeast Africa, oriented toward the Nile Valley and the Red Sea region - and Central or Equatorial Africa, some of whose people have retained classical African religions while others have adopted Christianity, and whose economies were part of the great Congo River system.", "Although much of Chad's distinctiveness comes from this diversity of influences, since independence the diversity has also been an obstacle to the creation of a national identity." ], [ "Land", "Although Chadian society is economically, socially, and culturally fragmented, the country's geography is unified by the Lake Chad Basin.", "Once a huge inland sea (the Pale-Chadian Sea) whose only remnant is shallow Lake Chad, this vast depression extends west into Nigeria and Niger.", "The larger, northern portion of the basin is bounded within Chad by the Tibesti Mountains in the northwest, the Ennedi Plateau in the northeast, the Ouaddaï Highlands in the east along the border with Sudan, the Guéra Massif in central Chad, and the Mandara Mountains along Chad's southwestern border with Cameroon.", "The smaller, southern part of the basin falls almost exclusively in Chad.", "It is delimited in the north by the Guéra Massif, in the south by highlands 250 kilometers south of the border with Central African Republic, and in the southwest by the Mandara Mountains.Lake Chad, located in the southwestern part of the basin at an altitude of 282 meters, surprisingly does not mark the basin's lowest point; instead, this is found in the Bodele and Djourab regions in the north-central and northeastern parts of the country, respectively.", "This oddity arises because the great stationary dunes (ergs) of the Kanem region create a dam, preventing lake waters from flowing to the basin's lowest point.", "At various times in the past, and as late as the 1870s, the Bahr el Ghazal Depression, which extends from the northeastern part of the lake to the Djourab, acted as an overflow canal; since independence, climatic conditions have made overflows impossible.North and northeast of Lake Chad, the basin extends for more than 800 kilometers, passing through regions characterized by great rolling dunes separated by very deep depressions.", "Although vegetation holds the dunes in place in the Kanem region, farther north they are bare and have a fluid, rippling character.", "From its low point in the Djourab, the basin then rises to the plateaus and peaks of the Tibesti Mountains in the north.", "The summit of this formation—as well as the highest point in the Sahara Desert—is Emi Koussi, a dormant volcano that reaches 3,414 meters above sea level.The basin's northeastern limit is the Ennedi Plateau, whose limestone bed rises in steps etched by erosion.", "East of the lake, the basin rises gradually to the Ouaddaï Highlands, which mark Chad's eastern border and also divide the Chad and Nile watersheds.", "These highland areas are part of the East Saharan montane xeric woodlands ecoregion.Southeast of Lake Chad, the regular contours of the terrain are broken by the Guéra Massif, which divides the basin into its northern and southern parts.", "South of the lake lie the floodplains of the Chari and Logone rivers, much of which are inundated during the rainy season.", "Farther south, the basin floor slopes upward, forming a series of low sand and clay plateaus, called koros, which eventually climb to 615 meters above sea level.", "South of the Chadian border, the koros divide the Lake Chad Basin from the Ubangi-Zaire river system." ], [ "Water systems", "Lake Chad in a 2001 satellite image.", "On the top, the changes from 1973 to 1997 are shown, with the lake shrinking.This astronaut photograph features one of the largest of a series of ten mostly fresh water lakes in the Ounianga Basin in the heart of the Sahara Desert of northeastern Chad.Permanent streams do not exist in northern or central Chad.", "Following infrequent rains in the Ennedi Plateau and Ouaddaï Highlands, water may flow through depressions called enneris and wadis.", "Often the result of flash floods, such streams usually dry out within a few days as the remaining puddles seep into the sandy clay soil.", "The most important of these streams is the Batha, which in the rainy season carries water west from the Ouaddaï Highlands and the Guéra Massif to Lake Fitri.Chari RiverChad's major rivers are the Chari and the Logone and their tributaries, which flow from the southeast into Lake Chad.", "Both river systems rise in the highlands of Central African Republic and Cameroon, regions that receive more than 1,250 millimeters of rainfall annually.", "Fed by rivers of Central African Republic, as well as by the Bahr Salamat, Bahr Aouk, and Bahr Sara rivers of southeastern Chad, the Chari River is about 1,200 kilometers long.", "From its origins near the city of Sarh, the middle course of the Chari makes its way through swampy terrain; the lower Chari is joined by the Logone River near N'Djamena.", "The Chari's volume varies greatly, from 17 cubic meters per second during the dry season to 340 cubic meters per second during the wettest part of the year.The Logone River is formed by tributaries flowing from Cameroon and Central African Republic.", "Both shorter and smaller in volume than the Chari, it flows northeast for 960 kilometers; its volume ranges from five to eighty-five cubic meters per second.", "At N'Djamena the Logone empties into the Chari, and the combined rivers flow together for thirty kilometers through a large delta and into Lake Chad.", "At the end of the rainy season in the fall, the river overflows its banks and creates a huge floodplain in the delta.The seventh largest lake in the world (and the fourth largest in Africa), Lake Chad is located in the sahelian zone, a region just south of the Sahara Desert.", "The Chari River contributes 95 percent of Lake Chad's water, an average annual volume of 40 billion cubic meters, 95% of which is lost to evaporation.", "The size of the lake is determined by rains in the southern highlands bordering the basin and by temperatures in the Sahel.", "Fluctuations in both cause the lake to change dramatically in size, from 9,800 square kilometers in the dry season to 25,500 at the end of the rainy season.Lake Chad also changes greatly in size from one year to another.", "In 1870 its maximum area was 28,000 square kilometers.", "The measurement dropped to 12,700 in 1908.In the 1940s and 1950s, the lake remained small, but it grew again to 26,000 square kilometers in 1963.The droughts of the late 1960s, early 1970s, and mid-1980s caused Lake Chad to shrink once again, however.", "The only other lakes of importance in Chad are Lake Fitri, in Batha Prefecture, and Lake Iro, in the marshy southeast." ], [ "Climate", "Chad map of Köppen climate classificationCar facing difficulties during rain seasonThe Lake Chad Basin embraces a great range of tropical climates from north to south, although most of these climates tend to be dry.", "Apart from the far north, most regions are characterized by a cycle of alternating rainy and dry seasons.", "In any given year, the duration of each season is determined largely by the positions of two great air masses—a maritime mass over the Atlantic Ocean to the southwest and a much drier continental mass.During the rainy season, winds from the southwest push the moister maritime system north over the African continent where it meets and slips under the continental mass along a front called the \"intertropical convergence zone\".", "At the height of the rainy season, the front may reach as far as Kanem Prefecture.", "By the middle of the dry season, the intertropical convergence zone moves south of Chad, taking the rain with it.", "This weather system contributes to the formation of three major regions of climate and vegetation.===Saharan region===A sandstorm at Abéché airport, Chad (2005).The Saharan region covers roughly the northern half of the country, including Borkou-Ennedi-Tibesti Prefecture along with the northern parts of Kanem, Batha, and Biltine prefectures.", "Much of this area receives only traces of rain during the entire year; at Faya-Largeau, for example, annual rainfall averages less than , and there are nearly 3800 hours of sunshine.", "Scattered small oases and occasional wells provide water for a few date palms or small plots of millet and garden crops.In much of the north, the average daily maximum temperature is about during January, the coolest month of the year, and about during May, the hottest month.", "On occasion, strong winds from the northeast produce violent sandstorms.", "In northern Biltine Prefecture, a region called the Mortcha plays a major role in animal husbandry.", "Dry for eight months of the year, it receives or more of rain, mostly during July and August.A carpet of green springs from the desert during this brief wet season, attracting herders from throughout the region who come to pasture their cattle and camels.", "Because very few wells and springs have water throughout the year, the herders leave with the end of the rains, turning over the land to the antelopes, gazelles, and ostriches that can survive with little groundwater.", "Northern Chad averages over 3500 hours of sunlight per year, the south somewhat less.===Sahelian region===The semiarid sahelian zone, or Sahel, forms a belt about wide that runs from Lac and Chari-Baguirmi prefectures eastward through Guéra, Ouaddaï, and northern Salamat prefectures to the Sudanese frontier.", "The climate in this transition zone between the desert and the southern sudanian zone is divided into a rainy season (from June to September) and a dry period (from October to May).In the northern Sahel, thorny shrubs and acacia trees grow wild, while date palms, cereals, and garden crops are raised in scattered oases.", "Outside these settlements, nomads tend their flocks during the rainy season, moving southward as forage and surface water disappear with the onset of the dry part of the year.", "The central Sahel is characterized by drought-resistant grasses and small woods.", "Rainfall is more abundant there than in the Saharan region.", "For example, N'Djamena records a maximum annual average rainfall of , while Ouaddaï Prefecture receives just a bit less.During the hot season, in April and May, maximum temperatures frequently rise above .", "In the southern part of the Sahel, rainfall is sufficient to permit crop production on unirrigated land, and millet and sorghum are grown.", "Agriculture is also common in the marshlands east of Lake Chad and near swamps or wells.", "Many farmers in the region combine subsistence agriculture with the raising of cattle, sheep, goats, and poultry.===Sudanian region===The humid ''sudanian'' zone includes the Sahel, the southern prefectures of Mayo-Kebbi, Tandjilé, Logone Occidental, Logone Oriental, Moyen-Chari, and southern Salamat.", "Between April and October, the rainy season brings between of precipitation.", "Temperatures are high throughout the year.", "Daytime readings in Moundou, the major city in the southwest, range from in the middle of the cool season in January to about in the hot months of March, April, and May.The sudanian region is predominantly East Sudanian savanna, or plains covered with a mixture of tropical or subtropical grasses and woodlands.", "The growth is lush during the rainy season but turns brown and dormant during the five-month dry season between November and March.", "Over a large part of the region, however, natural vegetation has yielded to agriculture.===2010 drought=== On 22 June, the temperature reached in Faya, breaking a record set in 1961 at the same location.", "Similar temperature rises were also reported in Niger, which began to enter a famine situation.On 26 July the heat reached near-record levels over Chad and Niger." ], [ "Area", "'''Area:'''''total:''1.284 million km2''land:''1,259,200 km2''water:''24,800 km2'''Area - comparative:'''Canada: smaller than the Northwest TerritoriesUS: slightly more than three times the size of California" ], [ "Boundaries", "'''Land boundaries:'''''total:''6,406 km''border countries:''Cameroon 1,116 km, Central African Republic 1,556 km, Libya 1,050 km, Niger 1,196 km, Nigeria 85 km, Sudan 1,403 km'''Coastline:'''0 km (landlocked)'''Maritime claims:'''none (landlocked)'''Elevation extremes:'''''lowest point:''Bodélé Depression 160 m''highest point:''Emi Koussi 3,415 m" ], [ "Land use and resources", "'''Natural resources:'''petroleum, uranium, natron, kaolin, fish (Chari River, Logone River), gold, limestone, sand and gravel, salt'''Land use:'''''arable land:''3.89%''permanent crops:''0.03%''other:''96.08% (2012)'''Irrigated land:'''302.7 km2 (2003)'''Total renewable water resources:'''43 km3 (2011)'''Freshwater withdrawal (domestic/industrial/agricultural):'''''total:''0.88 km3/yr (12%/12%/76%)''per capita:''84.81 m3/yr (2005)" ], [ "Environmental issues", "'''Natural hazards:'''hot, dry, dusty, Harmattan winds occur in north; periodic droughts; locust plagues'''Environment - current issues:'''inadequate supplies of potable water; improper waste disposal in rural areas contributes to soil and water pollution; desertification" ], [ "See also", "*2010 Sahel famine" ], [ "Extreme points", "This is a list of the extreme points of Chad, the points that are farther north, south, east or west than any other location.", "*Northernmost point - an unnamed location on the border with Libya, Borkou-Ennedi-Tibesti region*Easternmost point - the northern section of the Chad-Sudan border, Borkou-Ennedi-Tibesti region **Southernmost point - unnamed location on the border with Central African Republic at a confluence in the Lébé river, Logone Oriental region*Westernmost point - unnamed location west of the town of Kanirom and immediately north of Lake Chad, Lac Region''*Note: technically Chad does not have an easternmost point, the easternmost section of the border being formed by the 24° of longitude''" ], [ "References" ], [ "Sources", "*" ], [ "External links", "* – title=Field Listing: Geographic Coordinates.", "Geo-links for Geography of Chad.", "* Detailed map of Chad from www.izf.net" ] ]

[ [ "Demographics of Chad" ], [ "Introduction", "Demographics of Chad, Data of Our World in Data, year 2022 ; Number of inhabitants in millions.The people of Chad speak more than 100 languages and divide themselves into many ethnic groups.", "However, language and ethnicity are not the same.", "Moreover, neither element can be tied to a particular physical type.Although the possession of a common language shows that its speakers have lived together and have a common history, peoples also change languages.", "This is particularly so in Chad, where the openness of the terrain, marginal rainfall, frequent drought and famine, and low population densities have encouraged physical and linguistic mobility.", "Slave raids among non-Muslim peoples, internal slave trade, and exports of captives northward from the ninth to the twentieth centuries also have resulted in language changes.Anthropologists view ethnicity as being more than genetics.", "Like language, ethnicity implies a shared heritage, partly economic, where people of the same ethnic group may share a livelihood, and partly social, taking the form of shared ways of doing things and organizing relations among individuals and groups.", "Ethnicity also involves a cultural component made up of shared values and a common worldview.", "Like language, ethnicity is not immutable.", "Shared ways of doing things change over time and alter a group's perception of its own identity.Not only do the social aspects of ethnic identity change but the biological composition (or gene pool) also may change over time.", "Although most ethnic groups emphasize intermarriage, people are often proscribed from seeking partners among close relatives—a prohibition that promotes biological variation.", "In all groups, the departure of some individuals or groups and the integration of others also changes the biological component.The Chadian government has avoided official recognition of ethnicity.", "With the exception of a few surveys conducted shortly after independence, little data were available on this important aspect of Chadian society.", "Nonetheless, ethnic identity was a significant component of life in Chad.The peoples of Chad carry significant ancestry from Eastern, Central, Western, and Northern Africa.Chad's languages fall into ten major groups, each of which belongs to either theNilo-Saharan, Afro-Asiatic, or Niger–Congo language family.", "These represent three of the four major language families in Africa; only the Khoisan languages of southern Africa are not represented.", "The presence of such different languages suggests that the Lake Chad Basin may have been an important point of dispersal in ancient times." ], [ "Population", "A tribal delegation in ChadPeople of ChadAccording to the total population was in , compared to only 2 429 000 in 1950.The proportion of children below the age of 15 in 2010 was 45.4%, 51.7% was between 15 and 65 years of age, while 2.9% was 65 years or the country is projected to have a population of 34 millions peoples in 2050 and 61 millions peoples in 2100.Total populationPopulation aged 0–14 (%)Population aged 15–64 (%)Population aged 65+ (%) 19502 429 00037.857.84.4 19552 671 00039.156.84.1 19602 954 00040.355.93.8 19653 289 00041.554.73.8 19703 656 00042.054.23.8 19754 114 00042.853.43.8 19804 554 00044.052.33.7 19855 151 00045.251.23.6 19906 011 00045.850.73.5 19956 998 00045.950.83.3 20008 222 00045.951.03.1 20059 786 00045.851.23.0 201011 227 00045.451.72.9Age GroupMaleFemaleTotal% Total 5 452 483 5 587 390 11 039 873 100 0–4 1 129 693 1 100 985 2 230 678 20.21 5–9 1 012 471 987 297 1 999 768 18.11 10–14 700 015 650 633 1 350 648 12.23 15–19 502 894 557 494 1 060 388 9.61 20–24 382 122 482 768 864 890 7.83 25–29 320 063 433 622 753 685 6.83 30–34 277 322 335 402 612 724 5.55 35–39 241 971 260 515 502 485 4.55 40–44 215 887 214 181 430 068 3.90 45–49 163 952 139 357 303 308 2.75 50–54 147 725 133 019 280 744 2.54 55–59 84 938 62 817 147 755 1.34 60–64 92 696 85 024 177 720 1.61 65-69 48 054 37 398 85 452 0.77 70-74 56 059 49 289 105 348 0.95 75-79 24 148 17 371 41 518 0.38 80-84 24 947 21 486 46 433 0.42 85-89 9 086 5 833 14 919 0.14 90-94 6 852 5 465 12 317 0.11 95-99 5 113 3 609 8 722 0.08 100+ 1 323 1 200 2 523 0.02Age group MaleFemaleTotalPercent 0–14 2 842 179 2 738 915 5 581 094 50.55 15–64 2 429 569 2 704 199 5 133 768 46.50 65+ 175 582 141 651 317 233 2.87 Unknown 5 153 2 625 7 778 0.07" ], [ "Vital statistics", "Registration of vital events is in Chad not complete.", "The Population Departement of the United Nations prepared the following estimates.", "Live births per yearDeaths per yearNatural change per yearCBRCDRNCTFRIMRLife expectancy (years)1950  117,000  70,000  47,00046.727.818.96.06197.636.211951  119,000  72,000  47,00046.528.118.46.07196.536.341952  121,000  73,000  48,00046.428.118.36.09194.436.501953  123,000  74,000  49,00046.427.918.56.11192.336.841954  125,000  75,000  50,00046.327.718.56.13190.337.031955  127,000  76,000  51,00046.227.618.66.15188.337.211956  130,000  77,000  53,00046.127.318.86.17186.337.451957  132,000  78,000  54,00046.027.118.96.19184.337.661958  134,000  78,000  56,00045.926.819.16.21182.337.941959  136,000  79,000  57,00045.926.519.36.23180.338.191960  139,000  80,000  59,00045.726.319.46.25178.438.371961  141,000  80,000  61,00045.726.019.66.27176.538.631962  144,000  81,000  62,00045.625.819.86.29174.638.841963  146,000  82,000  64,00045.525.619.96.30172.839.071964  149,000  83,000  66,00045.425.320.26.32171.039.331965  152,000  85,000  67,00045.425.420.06.34169.739.121966  155,000  86,000  69,00045.425.320.26.36166.839.151967  158,000  87,000  71,00045.625.020.66.39164.239.481968  162,000  87,000  75,00045.824.621.26.43161.339.901969  166,000  88,000  79,00046.224.321.96.48158.340.271970  172,000  88,000  83,00046.724.122.66.53155.240.601971  177,000  92,000  85,00047.224.422.76.58153.540.191972  188,000  90,000  97,00049.023.625.46.85149.141.401973  192,000  92,000  100,00049.023.525.56.87148.741.781974  196,000  94,000  102,00048.823.525.46.86147.841.791975  200,000  96,000  104,00048.723.425.46.88147.041.871976  203,000  97,000  107,00048.623.125.56.89145.542.041977  206,000  98,000  109,00048.422.925.56.90144.642.261978  209,000  98,000  111,00048.222.725.56.89143.642.501979  212,000  99,000  113,00048.122.425.76.91142.642.811980  218,000  100,000  118,00048.222.126.16.91141.443.061981  205,000  97,000  108,00046.321.924.56.94141.043.311982  212,000  97,000  115,00046.921.425.56.96139.543.731983  242,000  102,000  140,00049.821.128.86.98138.044.181984  252,000  105,000  147,00050.421.029.47.02136.244.521985  245,000  103,000  142,00049.320.728.57.04135.045.051986  252,000  104,000  148,00049.420.428.97.07132.145.211987  268,000  116,000  153,00050.721.828.87.11130.442.801988  283,000  110,000  173,00051.720.231.57.15128.945.791989  295,000  114,000  182,00052.120.132.07.19127.045.881990  307,000  121,000  185,00052.420.731.67.22125.344.691991  312,000  120,000  192,00052.120.032.07.26124.245.941992  336,000  125,000  211,00053.319.933.47.30122.546.101993  349,000  129,000  221,00053.519.733.87.34120.946.321994  343,000  129,000  214,00052.119.532.57.31119.646.451995  355,000  131,000  224,00052.119.232.97.29118.246.711996  381,000  136,000  245,00053.018.934.07.29117.047.011997  390,000  139,000  251,00052.418.733.77.27115.647.221998  403,000  143,000  260,00052.218.533.77.27114.047.221999  413,000  146,000  267,00051.718.333.47.26112.447.372000  424,000  149,000  275,00051.318.133.27.25110.747.442001  436,000  151,000  285,00051.117.733.47.23108.847.852002  444,000  154,000  290,00050.317.432.97.20106.847.952003  457,000  157,000  300,00049.917.132.87.18105.148.212004  481,000  162,000  318,00050.317.033.37.16103.448.232005  503,000  168,000  335,00050.316.833.57.13101.548.312006  517,000  173,000  344,00049.916.733.27.1299.748.292007  533,000  175,000  359,00049.716.333.47.0997.548.752008  546,000  177,000  368,00049.216.033.27.0695.449.022009  562,000  181,000  381,00048.915.833.27.0293.249.202010  580,000  183,000  397,00048.815.433.36.9991.149.582011  595,000  185,000  410,00048.415.133.36.9588.950.012012  612,000  187,000  426,00048.014.633.46.9186.650.542013  626,000  190,000  437,00047.514.433.16.8484.550.782014  643,000  192,000  451,00047.014.033.06.7882.651.202015  657,000  194,000  463,00046.413.732.76.7180.651.592016  663,000  194,000  469,00045.513.332.26.6278.552.082017  676,000  197,000  479,00044.813.031.86.5476.352.312018  691,000  197,000  494,00044.412.731.76.4674.252.832019  714,000  200,000  514,00044.212.431.96.4172.253.262020  730,000  208,000  522,00043.812.531.46.3570.252.782021  745,000  215,000  530,00043.412.530.96.2668.252.53 Source: UN DESA, World Population Prospects, 2022===Fertility and births===Total Fertility Rate (TFR) (Wanted Fertility Rate) and Crude Birth Rate (CBR): Year CBR (Total) TFR (Total) CBR (Urban) TFR (Urban) CBR (Rural) TFR (Rural) 1996-97 47,8 6,6 (6,3) 44,4 6,1 (5,7) 48,8 6,8 (6,5) 2004 44,6 6,3 (6,1) 41,8 5,7 (5,5) 45,3 6,5 (6,2) 2014-15 40,5 6,4 (6,1) 36,0 5,4 (5,1) 41,8 6,8 (6,5)Fertility data as of 2014-2015 (DHS Program): Region Total fertility rate Percentage of women age 15-49 currently pregnant Mean number of children ever born to women age 40-49Batha 7.3 12.2 8.3Borkou, Tibesti 5.3 9.6 6.4Chari Baguirmi 6.6 16.1 7.7Guéra 6.7 14.6 8.4Hadjer-Lamis 6.8 14.5 8.4Kanem 6.0 14.8 7.1Lac 5.4 14.7 7.9Logone Occidental 6.4 12.7 7.6Logone Oriental 7.6 12.7 8.3Mandoul 6.5 12.7 7.7Mayo Kebbi Est 6.7 15.0 7.3Mayo Kebbi Ouest 7.5 13.8 7.9Moyen Chari 5.5 12.6 6.8Ouaddaï 6.1 13.1 7.1Salamat 6.5 19.7 8.0Tandjilé 7.1 13.1 8.0Wadi Fira 5.9 12.2 6.5N’Djaména 5.2 9.4 6.5Barh El Gazal 5.6 14.5 7.1Ennedi Est, Ennedi Ouest 5.0 13.4 6.3Sila 6.7 19.6 7.7" ], [ "Religions", "The separation of religion from social structure in Chad represents a false dichotomy, for they are perceived as two sides of the same coin.", "Three religious traditions coexist in Chad- classical African religions, Islam, and Christianity.", "None is monolithic.", "The first tradition includes a variety of ancestor and/or place-oriented religions whose expression is highly specific.", "Islam, although characterized by an orthodox set of beliefs and observances, also is expressed in diverse ways.", "Christianity arrived in Chad much more recently with the arrival of Europeans.", "Its followers are divided into Roman Catholics and Protestants (including several denominations); as with Chadian Islam, Chadian Christianity retains aspects of pre-Christian religious belief.The number of followers of each tradition in Chad is unknown.", "Estimates made in 1962 suggested that 35 percent of Chadians practiced classical African religions, 55 percent were Muslims, and 10 percent were Christians.", "In the 1970s and 1980s, this distribution undoubtedly changed.", "Observers report that Islam has spread among the Hadjarai peoples and other non-Muslim populations of the Saharan and sahelian zones.", "However, the proportion of Muslims may have fallen, because the birthrate among the followers of traditional religions and Christians in southern Chad is thought to be higher than that among Muslims.", "In addition, the upheavals since the mid-1970s have resulted in the departure of some missionaries; whether or not Chadian Christians have been numerous enough and sufficiently organized to attract more converts since that time is unknown." ], [ "Other demographic statistics", "Population, fertility rate and net reproduction rate, United Nations estimatesDemographic statistics according to the World Population Review in 2022.", "*One birth every 45 seconds\t*One death every 3 minutes\t*One net migrant every 1440 minutes\t*Net gain of one person every 1 minutesThe following demographic statistics are from the CIA World Factbook.===Population===:17,963,211 (2022 est.", "):15,833,116 (July 2018 est.", "):12,075,985 (2017 est.", ")===Religions===Muslim 52.1%, Protestant 23.9%, Roman Catholic 20%, animist 0.3%, other Christian 0.2%, none 2.8%, unspecified 0.7% (2014-15 est.", ")===Age structure===Population pyramid of Chad in 2020:''0-14 years:'' 47.43% (male 4,050,505/female 3,954,413):''15-24 years:'' 19.77% (male 1,676,495/female 1,660,417):''25-54 years:'' 27.14% (male 2,208,181/female 2,371,490):''55-64 years:'' 3.24% (male 239,634/female 306,477):''65 years and over:'' 2.43% (2020 est.)", "(male 176,658/female 233,087):''0-14 years:'' 48.12% (male 3,856,001 /female 3,763,622):''15-24 years:'' 19.27% (male 1,532,687 /female 1,518,940):''25-54 years:'' 26.95% (male 2,044,795 /female 2,222,751):''55-64 years:'' 3.25% (male 228,930 /female 286,379):''65 years and over:'' 2.39% (male 164,257 /female 214,754) (2018 est.", ")===Median age===:total: 16.1 years.", "Country comparison to the world: 223rd:male: 15.6 years:female: 16.5 years (2020 est.", "):total: 15.8 years.", "Country comparison to the world: 226th:male: 15.3 years :female: 16.3 years (2018 est.", "):Total: 17.8 years:Male: 16.8 years:Female: 18.8 years (2017 est.", ")===Population growth rate===:3.09% (2022 est.)", "Country comparison to the world: 10th:3.23% (2018 est.)", "Country comparison to the world: 5th===Birth rate===:40.45 births/1,000 population (2022 est.)", "Country comparison to the world: 6th:43 births/1,000 population (2018 est.)", "Country comparison to the world: 4th===Death rate===:9.45 deaths/1,000 population (2022 est.)", "Country comparison to the world: 49th:10.5 deaths/1,000 population (2018 est.)", "Country comparison to the world: 26th===Net migration rate===:-0.13 migrant(s)/1,000 population (2022 est.)", "Country comparison to the world: 105th:-3.2 migrant(s)/1,000 population (2017 est.)", "Country comparison to the world: 176th===Total fertility rate===:5.46 children born/woman (2022 est.)", "Country comparison to the world: 5th:5.9 children born/woman (2018 est.)", "Country comparison to the world: 4th===Mother's mean age at first birth===:18.1 years (2014/15 est.", "):note: median age at first birth among women 25-49===Dependency ratios===:total dependency ratio: 100.2 (2015 est.", "):youth dependency ratio: 95.2 (2015 est.", "):elderly dependency ratio: 4.9 (2015 est.", "):potential support ratio: 20.3 (2015 est.", ")===Contraceptive prevalence rate===:8.1% (2019):5.7% (2014/15)===Urbanization===:''urban population:'' 24.1% of total population (2022):''rate of urbanization:'' 4.1% annual rate of change (2020-25 est.", "):''urban population:'' 23.1% of total population (2018):''rate of urbanization:'' 3.88% annual rate of change (2015-20 est.", ")===Sex ratio===:At birth: 1.04 male(s)/female:Under 15 years: 1.01 male(s)/female:15–64 years: 0.92 male(s)/female:65 years and over: 0.66 male(s)/female:Total population: 0.96 male(s)/female (2006 est.", ")===Life expectancy at birth===:total population: 59.15 years.", "Country comparison to the world: 222nd:male: 57.32 years:female: 61.06 years (2022 est.", "):total population: 57.5 years (2018 est.)", "Country comparison to the world: 214th:male: 55.7 years (2018 est.", "):female: 59.3 years (2018 est.", "):Total population: 50.6 years:Male: 49.4 years:Female: 51.9 years (2017 est.", ")===HIV/AIDS===:Adult prevalence rate: 1.3% (2017 est.", "):People living with HIV/AIDS: 110,000(2017 est.", "):Deaths: 3,100 (2017 est.", ")===Children under the age of 5 years underweight===:28.8% (2015)===Major infectious diseases===:degree of risk: very high (2020):food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever:vectorborne diseases: malaria and dengue fever:water contact diseases: schistosomiasis:animal contact diseases: rabies:respiratory diseases: meningococcal meningitisnote: on 21 March 2022, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Chad is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine===Child marriage===:women married by age 15: 24.2% (2019):women married by age 18: 60.6% (2019):men married by age 18: 8.1% (2019 est.", ")===Nationality===:Noun: Chadian(s):Adjective: Chadian===Ethnic groups===The peoples of Chad carry significant ancestry from Eastern, Central, Western, and Northern Africa.", ":200 distinct groups*In the north and center: Arabs, Tubu (Daza, Teda), Zaghawa, Kanembu, Wadai, Baguirmi, Hadjarai, Fulani, Kotoko, Hausa, Bulala, and Maba, most of whom are Muslim*In the south: Sara (Ngambaye, Mbaye, Goulaye), Mundang, Mussei, Massa, most of whom are Christian or animistAbout 5,000 French citizens live in Chad.===Religions===*Islam 51.8% *Roman Catholic 20.3%*Protestant 23.5%*Animist 0.6%*Other Christians 0.3%*Unknown 0.6%*None 2.9% ===Languages===:Arabic (official), French (official), Sara (in south), more than 120 languages and dialects===Literacy===:Definition: age 15 and over can read and write French or Arabic:total population: 22.3% (2016 est.", "):male: 31.3% (2016 est.", "):female: 14% (2016 est.", ")===School life expectancy (primary to tertiary education)===:total: 7 years:male: 9 years:female: 6 years (2015):total: 8 years (2014):male: 9 years (2014):female: 6 years (2014)" ], [ "Notes" ], [ "References", "*'''Attribution:'''" ] ]

[ [ "Politics of Chad" ], [ "Introduction", "The '''politics of Chad''' take place in a framework of a presidential republic, whereby the President of Chad is both head of state and head of government.", "Executive power is exercised by the government.", "Legislative power is vested in both the government and parliament.", "Chad is one of the most corrupt countries in the world.In May 2013, security forces in Chad foiled a coup against the President Idriss Deby that had been in preparation for several months.", "In April 2021, President Déby was injured by the rebel group Front Pour l'Alternance et La Concorde au Tchad (FACT).", "He succumbed to his injuries on April 20, 2021.His presidency was taken by his family member Mahamat Déby in April of 2021.This resulted in both the National Assembly and Chadian Government being dissolved and replaced with a Transitional Military Council.The National Transitional Council will oversee the transition to democracy." ], [ "Executive branch", "|PresidentMahamat DébyPatriotic Salvation Movement20 April 2021Former President Idriss Deby in 2014Chad's executive branch is headed by the President and dominates the Chadian political system.", "Following the military overthrow of Hissène Habré in December 1990, Idriss Déby won the presidential elections in 1996 and 2001.The constitutional basis for the government is the 1996 constitution, under which the president was limited to two terms of office until Déby had that provision repealed in 2005.The president has the power to appoint the Council of State (or cabinet), and exercises considerable influence over appointments of judges, generals, provincial officials and heads of Chad's parastatal firms.", "In cases of grave and immediate threat, the president, in consultation with the National Assembly President and Council of State, may declare a state of emergency.", "Most of the key advisors for former president Déby were members of the Zaghawa clan, although some southern and opposition personalities were represented in his government." ], [ "Legislative branch", "According to the 1996 constitution, the National Assembly deputies are elected by universal suffrage for 4-year terms.", "The Assembly holds regular sessions twice a year, starting in March and October, and can hold special sessions as necessary and called by the prime minister.", "Deputies elect a president of the National Assembly every 2 years.", "Assembly deputies or members of the executive branch may introduce legislation; once passed by the Assembly, the president must take action to either sign or reject the law within 15 days.", "The National Assembly must approve the prime minister's plan of government and may force the prime minister to resign through a majority vote of no-confidence.", "However, if the National Assembly rejects the executive branch's program twice in one year, the president may disband the Assembly and call for new legislative elections.", "In practice, the president exercises considerable influence over the National Assembly through the MPS party structure." ], [ "Judicial branch", "Despite the constitution's guarantee of judicial independence from the executive branch, the president names most key judicial officials.", "The Supreme Court is made up of a chief justice, named by the president, and 15 councilors chosen by the president and National Assembly; appointments are for life.", "The Constitutional Council, with nine judges elected to 9-year terms, has the power to review all legislation, treaties and international agreements prior to their adoption.", "The constitution recognizes customary and traditional law in locales where it is recognized and to the extent it does not interfere with public order or constitutional guarantees of equality for all citizens." ], [ "Political parties and elections", "===Presidential elections======Parliamentary elections===" ], [ "International organization participation", "ACCT, ACP, AfDB, AU, BDEAC, CEMAC, FAO, FZ, G-77, IBRD, ICAO, ICCt, ICFTU, ICRM, IDA, IDB, IFAD, IFC, IFRCS, ILO, IMF, Interpol, IOC, ITU, MIGA, NAM, OIC, ONUB, OPCW, UN, UNCTAD, UNESCO, UNIDO, UNOCI, UPU, WCL, WHO, WIPO, WMO, WToO, WTrO" ], [ "2021 government shakeup", "On 20 April 2021, following the death of longtime Chad President Idriss Déby, the Military of Chad released a statement confirming that both the Government of Chad and the nation's National Assembly had been dissolved and that a Transitional Military Council led by Déby's son Mahamat would lead the nation for at least 18 months.", "Among the 40-member transitional government were nine women including Lydie Beassemda, Fatime Goukouni Weddeye and Isabelle Housna Kassire.", "Following protests on 14 May 2022, the authorities in Chad detained several members of civil society organizations.", "The protests were organized in N’Djamena, and other cities across the country by Chadian civil society organizations, united under the coalition Wakit Tamma." ], [ "See also", "*Kamougue Assoum" ], [ "References" ] ]

[ [ "Economy of Chad" ], [ "Introduction", "The '''economy of Chad''' suffers from the landlocked country's geographic remoteness, drought, lack of infrastructure, and political turmoil.", "About 85% of the population depends on agriculture, including the herding of livestock.", "Of Africa's Francophone countries, Chad benefited least from the 50% devaluation of their currencies in January 1994.Financial aid from the World Bank, the African Development Bank, and other sources is directed largely at the improvement of agriculture, especially livestock production.", "Because of lack of financing, the development of oil fields near Doba, originally due to finish in 2000, was delayed until 2003.It was finally developed and is now operated by ExxonMobil.", "In terms of gross domestic product, Chad ranks 147th globally with $11.051 billion as of 2018." ], [ "Agriculture", "Chad produced in 2018:* 969 thousand tons of sorghum;* 893 thousand tons of peanut butter;* 756 thousand tons of millet;* 484 thousand tonnes of yam (8th largest producer in the world);* 475 thousand tons of sugarcane;* 437 thousand tons of maize;* 284 thousand tons of cassava;* 259 thousand tons of rice;* 255 thousand tons of sweet potato;* 172 thousand tons of sesame seed;* 151 thousand tons of bean;* 120 thousand tons of cotton;In addition to smaller productions of other agricultural products." ], [ "Macro-economic trend", "The following table shows the main economic indicators in 1980–2017.Year GDP(in bil.", "US$ PPP) GDP per capita(in US$ PPP)GDP(in bil.", "US$ nominal) GDP Growth(real) Government debt(Percentage of GDP) 1980 1.90 4330.74 −6.0% ... 1985 3.04 6100.98 7.9% ... 1990 4.41 7811.83 3.2% ... 1995 5.77 8741.64 −0.8% ... 2000 7.12 9521.57 −0.9% 68% 2005 16.09 1,7816.68 28.5% 28% 2006 16.69 1,8027.45 0.6% 26% 2007 17.70 1,8648.69 3.3% 22% 2008 18.60 1,91110.43 3.1% 20% 2009 19.51 1,9569.32 4.1% 32% 2010 22.44 2,19510.70 13.6% 30% 2011 22.93 2,18812.18 0.1% 31% 2012 25.41 2,36612.41 8.8% 29% 2013 27.30 2,48012.99 5.8% 31% 2014 29.71 2,63314.00 6.9% 42% 2015 30.56 2,64210.95 1.8% 44% 2016 28.96 2,44310.20 −6.4% 52% 2017 28.55 2,34410.08 −3.1% 53%" ], [ "Other statistics", "'''GDP:'''purchasing power parity – $28.62 billion (2017 est.", ")'''GDP – real growth rate:'''-3.1% (2017 est.", ")'''GDP – per capita:'''$2,300 (2017 est.", ")'''Gross national saving:''' 15.5% of GDP (2017 est.", ")'''GDP – composition by sector:'''''agriculture:''52.3% (2017 est.)", "''industry:''14.7% (2017 est.)", "''services:''33.1% (2017 est.", ")'''Population below poverty line::'''46.7% (2011 est.", ")'''Distribution of family income – Gini index:'''43.3 (2011 est.", ")'''Inflation rate (consumer prices):'''-0.9% (2017 est.", ")'''Labor force:'''5.654 million (2017 est.", ")'''Labor force – by occupation:'''agriculture 80%, industry and services 20% (2006 est.", ")'''Budget:'''''revenues:''1.337 billion (2017 est.)", "''expenditures:''1.481 billion (2017 est.", ")'''Budget surplus (+) or deficit (-):'''-1.5% (of GDP) (2017 est.", ")'''Public debt:''' 52.5% of GDP (2017 est.)", "'''Industries:'''oil, cotton textiles, brewing, natron (sodium carbonate), soap, cigarettes, construction materials'''Industrial production growth rate:'''-4% (2017 est.", ")'''electrification:''' total population: 4% (2013)'''electrification:''' urban areas: 14% (2013)'''electrification:''' rural areas: 1% (2013)'''Electricity – production:'''224.3 million kWh (2016 est.", ")'''Electricity – production by source:'''''fossil fuel:''98%''hydro:''0%''nuclear:''0%''other renewable:''3% (2017)'''Electricity – consumption:'''208.6 million kWh (2016 est.", ")'''Electricity – exports:'''0 kWh (2016 est.", ")'''Electricity – imports:'''0 kWh (2016 est.", ")'''Agriculture – products:'''cotton, sorghum, millet, peanuts, sesame, corn, rice, potatoes, onions, cassava (manioc, tapioca), cattle, sheep, goats, camels'''Exports:'''$2.464 billion (2017 est.", ")'''Exports – commodities:'''oil, livestock, cotton, sesame, gum arabic, shea butter'''Exports – partners:'''US 38.7%, China 16.6%, Netherlands 15.7%, UAE 12.2%, India 6.3% (2017)'''Imports:'''$2.16 billion (2017 est.", ")'''Imports – commodities:'''machinery and transportation equipment, industrial goods, foodstuffs, textiles'''Imports – partners:'''China 19.9%, Cameroon 17.2%, France 17%, US 5.4%, India 4.9%, Senegal 4.5% (2017)'''Debt – external:'''$1.724 billion (31 December 2017 est.", ")'''Reserves of foreign exchange and gold:'''$22.9 million (31 December 2017 est.)" ], [ "See also", "* Chad* Economy of Africa* Petroleum industry in Chad* United Nations Economic Commission for Africa" ], [ "References", ";General*" ], [ "External links", "* * Chad latest trade data on ITC Trade Map* World Bank – Chad-Cameroon Pipeline Project" ] ]

[ [ "Telecommunications in Chad" ], [ "Introduction", "'''Telecommunications in Chad''' include radio, television, fixed and mobile telephones, and the Internet." ], [ "Radio and television", "'''Radio stations:'''* state-owned radio network, Radiodiffusion Nationale Tchadienne (RNT), operates national and regional stations; about 10 private radio stations; some stations rebroadcast programs from international broadcasters (2007);* 2 AM, 4 FM, and 5 shortwave stations (2001).", "'''Radios:'''1.7 million (1997).", "'''Television stations:'''* 1 state-owned TV station, Tele Tchad (2007);* 1 station (2001).", "'''Television sets:'''10,000 (1997).Radio is the most important medium of mass communication.", "State-run Radiodiffusion Nationale Tchadienne operates national and regional radio stations.", "Around a dozen private radio stations are on the air, despite high licensing fees, some run by religious or other non-profit groups.", "The BBC World Service (FM 90.6) and Radio France Internationale (RFI) broadcast in the capital, N'Djamena.", "The only television station, Tele Tchad, is state-owned.State control of many broadcasting outlets allows few dissenting views.", "Journalists are harassed and attacked.", "On rare occasions journalists are warned in writing by the High Council for Communication to produce more \"responsible\" journalism or face fines.", "Some journalists and publishers practice self-censorship.", "On 10 October 2012, the High Council on Communications issued a formal warning to La Voix du Paysan, claiming that the station's live broadcast on 30 September incited the public to \"insurrection against the government.\"", "The station had broadcast a sermon by a bishop who criticized the government for allegedly failing to use oil wealth to benefit the region." ], [ "Telephones", "'''Calling code:''' +235'''International call prefix:''' 00'''Main lines:'''* 29,900 lines in use, 176th in the world (2012);* 13,000 lines in use, 201st in the world (2004).", "'''Mobile cellular:'''* 4.2 million lines, 119th in the world (2012);* 210,000 lines, 155th in the world (2005).", "'''Telephone system:''' inadequate system of radiotelephone communication stations with high costs and low telephone density; fixed-line connections for less than 1 per 100 persons coupled with mobile-cellular subscribership base of only about 35 per 100 persons (2011).", "'''Satellite earth stations:''' 1 Intelsat (Atlantic Ocean) (2011)." ], [ "Internet", "'''Top-level domain:''' .td'''Internet users:'''* 230,489 users, 149th in the world; 2.1% of the population, 200th in the world (2012);* 168,100 users, 145th in the world (2009);*   35,000 users, 167th in the world (2005).", "'''Fixed broadband:''' 18,000 subscriptions, 132nd in the world; 0.2% of the population, 161st in the world (2012).", "'''Wireless broadband:''' Unknown (2012).", "'''Internet hosts:'''* 6 hosts, 229th in the world (2012);* 9 hosts, 217th in the world (2006).", "'''IPv4:''' 4,096 addresses allocated, less than 0.05% of the world total, 0.4 addresses per 1000 people (2012).===Internet censorship and surveillance===There are no government restrictions on access to the Internet or credible reports that the government monitors e-mail or Internet chat rooms.The constitution provides for freedom of opinion, expression, and press, but the government does not always respect these rights.", "Private individuals are generally free to criticize the government without reprisal, but reporters and publishers risk harassment from authorities when publishing critical articles.", "The 2010 media law abolished prison sentences for defamation and insult, but prohibits \"inciting racial, ethnic, or religious hatred,\" which is punishable by one to two years in prison and a fine of one to three million CFA francs ($2,000 to $6,000)." ], [ "See also", "* Radiodiffusion Nationale Tchadienne, state-operated national radio broadcaster.", "* Télé Tchad, state-operated national TV broadcaster.", "* Societe des Telecommunications Internationales du Tchad (SotelTchad), telecommunications parastatal providing landline telephone and Internet services.", "* List of terrestrial fibre optic cable projects in Africa* Media of Chad* Economy of Chad* Chad" ], [ "References", "* *" ], [ "External links", "* \"Chad still on pace for ICT policy goals\", oAfrica, 20 November 2010." ] ]

[ [ "Transport in Chad" ], [ "Introduction", "Rebuilt Bridge in south west of Chad over the Bragoto RiverTransport infrastructure within Chad is generally poor, especially in the north and east of the country.", "River transport is limited to the south-west corner.", "As of 2011 Chad had no railways though two lines are planned - from the capital to the Sudanese and Cameroonian borders during the wet season, especially in the southern half of the country.", "In the north, roads are merely tracks across the desert and land mines continue to present a danger.", "Draft animals (horses, donkeys and camels) remain important in much of the country.Fuel supplies can be erratic, even in the south-west of the country, and are expensive.", "Elsewhere they are practically non-existent." ], [ "Railways", "As of 2011 Chad had no railways.", "Two lines were planned to Sudan and Cameroon from the capital, with construction expected to start in 2012.No operative lines were listed as of 2019.In 2021, an ADB study was funded for that rail link from Cameroon to Chad." ], [ "Highways", "Road transport during wet seasonThrough the desert near the Chad-Libya borderAs at 2018 Chad had a total of 44,000 km of roads of which approximately 260 km are paved.", "Some, but not all of the roads in the capital N'Djamena are paved.", "Outside of N'Djamena there is one paved road which runs from Massakory in the north, through N'Djamena and then south, through the cities of Guélengdeng, Bongor, Kélo and Moundou, with a short spur leading in the direction of Kousseri, Cameroon, near N'Djamena.", "Expansion of the road towards Cameroon through Pala and Léré is reportedly in the preparatory stages." ], [ "Waterways", "As at 2012, Chari and Logone Rivers were navigable only in wet season (2002).", "Both flow northwards, from the south of Chad, into Lake Chad." ], [ "Pipelines", "Since 2003, a 1,070 km pipeline has been used to export crude oil from the oil fields around Doba to offshore oil-loading facilities on Cameroon's Atlantic coast at Kribi.The CIA World Factbook however cites only 582 km of pipeline in Chad itself as at 2013." ], [ "Seaports and harbors", "None (landlocked).Chad's main routes to the sea are:* From N'Djamena and the south west of Chad:** By road to Ngaoundéré, in Cameroon, and then by rail to Douala** By road to Maiduguri, in Nigeria, and then by rail to Port Harcourt* From the north and east of Chad:** By road across the Sahara desert to LibyaIn colonial times, the main access was by road to Bangui, in the Central African Republic, then by river boat to Brazzaville, and onwards by rail from Brazzaville to Pointe Noire, on Congo's Atlantic coast.", "This route is now little used.There is also a route across Sudan, to the Red Sea, but very little trade goes this way.Links with Niger, north of Lake Chad, are practically nonexistent; it is easier to reach Niger via Cameroon and Nigeria." ], [ "Airports", " Chad had an estimated 58 airports, only 9 of which had paved runways.", "In 2015, scheduled airlines in Chad carried approximately 28,332 passengers.=== Airports with paved runways ===Statistics on airports with paved runways as of 2017: Runway length Airports over 2 4 2 0 under 1 TOTAL 9List of airports with paved runways:* Abeche Airport* Bol Airport* Faya-Largeau Airport* Moundou Airport* N'Djamena International Airport* Sarh Airport=== Airports - with unpaved runways ===Statistics on airports with unpaved runways as of 2013: Runway length Airports over 1 2 14 22 under 11 TOTAL 50=== Airline ===SAGA Airline of Chad - see http://www.airsaga.com" ], [ "Ministry of Transport", "The Ministry is represented at the regional level by the Regional Delegations, which have jurisdiction over a part of the National Territory as defined by Decree No.", "003 / PCE / CTPT / 91.Their organization and responsibilities are defined by Order No.", "006 / MTPT / SE / DG / 92.The Regional Delegations are::*The Regional Delegation of the Center covering the regions of Batha, Guéra and Salamat with headquarters in Mongo;:*The Regional Delegation of the Center-Ouest covering the regions of Chari Baguirmi and Hatier Lamis with headquarters Massakory;:*The North-West Regional Delegation covering the Kanem and Lake regions with headquarters in Mao;:*The Western Regional Delegation covering the areas of Mayo-East Kebbi, Mayo-West Kebbi and Tandjile with headquarters in Bongor;:*The Eastern Regional Delegation covering the regions of Wadi Fira and Ouaddai with headquarters in Abéché;:*The South-East Regional Delegation covering the Mandoul and Moyen Chari regions with headquarters in Sarh;:*The Southwest Regional Delegation covering the regions of Logone Occidental and Logone Orientai with headquarters in Moundou;:*The Northern Regional Delegation covering the BET region with headquarters in Faya.Each Regional Delegation is organized into regional services, namely: the Regional Roads Service, the Regional Transport Service, the Civilian Buildings Regional Service and, as needed, other regional services may be established in one or more Delegations ." ], [ "See also", "* Chad* Economy of Chad" ], [ "References" ], [ "External links", "* ; Maps* UN Map* UNHCR Atlas Map" ] ]

[ [ "Chad National Army" ], [ "Introduction", "The '''Chad National Army''' (; , '''ANT''') consists of the five Defence and Security Forces listed in Article 185 of the Chadian Constitution that came into effect on 4 May 2018.These are the National Army ((including Ground Forces, and Air Force), the National Gendarmerie), the National Police, the National and Nomadic Guard (GNNT) and the Judicial Police.", "Article 188 of the Constitution specifies that National Defence is the responsibility of the Army, Gendarmerie and GNNT, whilst the maintenance of public order and security is the responsibility of the Police, Gendarmerie and GNNT." ], [ "History", "Chadian Eland Mk7 armoured car.From independence through the period of the presidency of Félix Malloum (1975–79), the official national army was known as the Chadian Armed Forces (Forces Armées Tchadiennes—FAT).", "Composed mainly of soldiers from southern Chad, FAT had its roots in the army recruited by France and had military traditions dating back to World War I.", "FAT lost its status as the legal state army when Malloum's civil and military administration disintegrated in 1979.Although it remained a distinct military body for several years, FAT was eventually reduced to the status of a regional army representing the south.After Habré consolidated his authority and assumed the presidency in 1982, his victorious army, the Armed Forces of the North (Forces Armées du Nord—FAN), became the nucleus of a new national army.", "The force was officially constituted in January 1983, when the various pro-Habré contingents were merged and renamed the Chadian National Armed Forces (Forces Armées Nationales Tchadiennes—FANT).The Military of Chad was dominated by members of Toubou, Zaghawa, Kanembou, Hadjerai, and Massa ethnic groups during the presidency of Hissène Habré.", "Later Chadian president Idriss Déby revolted and fled to the Sudan, taking with him many Zaghawa and Hadjerai soldiers in 1989.Chad's armed forces numbered about 36,000 at the end of the Habré regime, but swelled to an estimated 50,000 in the early days of Déby's rule.", "With French support, a reorganization of the armed forces was initiated early in 1991 with the goal of reducing its numbers and making its ethnic composition reflective of the country as a whole.", "Neither of these goals was achieved, and the military is still dominated by the Zaghawa.In 2004, the government discovered that many of the soldiers it was paying did not exist and that there were only about 19,000 soldiers in the army, as opposed to the 24,000 that had been previously believed.", "Government crackdowns against the practice are thought to have been a factor in a failed military mutiny in May 2004.Renewed conflict, in which the Chadian military is involved, came in the form of a civil war against Sudanese-backed rebels.", "Chad successfully managed to repel many rebel movements, albeit with some losses (see Battle of N'Djamena (2008)).", "The army used its artillery systems and tanks, but well-equipped insurgents probably managed to destroy over 20 of Chad's 60 T-55 tanks, and probably shot down a Mi-24 Hind gunship, which bombed enemy positions near the border with Sudan.", "In November 2006 Libya supplied Chad with four Aermacchi SF.260W light attack planes.", "They were used to strike enemy positions by the Chadian Air Force, but one was shot down by rebels.", "During the 2008 battle of N'Djamena, gunships and tanks were put to good use, pushing armed militia forces back from the Presidential palace.", "The battle impacted the highest levels of the army leadership, as Daoud Soumain, its Chief of Staff, was killed.On March 23, 2020 a Chadian army base was ambushed by fighters of the jihadist insurgent group Boko Haram.", "The army lost 92 servicemen in one day.", "In response, President Déby launched an operation dubbed \"Wrath of Boma\".", "According to Canadian counter terrorism St-Pierre, numerous external operations and rising insecurity in the neighboring countries had recently overstretched the capacities of the Chadian armed forces.After the death of President Idriss Déby on 19 April 2021 in fighting with FACT rebels, his son General Mahamat Idriss Déby was named interim president and head of the armed forces." ], [ "Budget", "The CIA World Factbook estimates the military budget of Chad to be 4.2% of GDP as of 2006..", "Given the then GDP ($7.095 bln) of the country, military spending was estimated to be about $300 million.", "This estimate however dropped after the end of the Civil war in Chad (2005–2010) to 2.0% as estimated by the World Bank for the year 2011.There aren't any more recent estimates available." ], [ "External deployments", "*UN missions*non-UN missionsChad participated in a peace mission under the authority of African Union in the neighboring Central African Republic to try to pacify the recent conflict, but has chosen to withdraw after its soldiers were accused of shooting into a marketplace, unprovoked, according to BBC." ], [ "See also", "* Chad Air Force* Chadian Armed Forces* Chadian National Armed Forces* Nomad and National Guard" ], [ "Notes" ], [ "References", "*R. Hure \"L'Armee d' Afrique 1830-1962\"*John Keegan \"World Armies\" *\"Economic Development and the Libya-Chad Wars,\" Chapter 12 in Kenneth Pollack, ''Armies of Sand: The Past, Present, and Future of Arab Military Effectiveness,'' Oxford University Press, New York, 2019.", "** Pages à modifier :https://en.wikip" ] ]

[ [ "Foreign relations of Chad" ], [ "Introduction", "The '''foreign relations of Chad''' are significantly influenced by the desire for oil revenue and investment in Chadian oil industry and support for former Chadian President Idriss Déby.", "Chad is officially non-aligned but has close relations with France, the former colonial power.", "Relations with neighbouring Libya, and Sudan vary periodically.", "Lately, the Idris Déby regime waged an intermittent proxy war with Sudan.", "Aside from those two countries, Chad generally enjoys good relations with its neighbouring states.Diplomatic relations of Chad" ], [ "Africa", "Although relations with Libya improved with the presidency of Idriss Déby, strains persist.", "Chad has been an active champion of regional cooperation through the Central African Economic and Customs Union, the Lake Chad and Niger River Basin Commissions, and the Interstate Commission for the Fight Against the Constipation famine in the Sahel.Delimitation of international boundaries in the vicinity of Lake Chad, the lack of which led to border incidents in the past, has been completed and awaits ratification by Cameroon, Chad, Niger, and Nigeria.", "Country Formal Relations BeganNotes18 August 1975Both countries established diplomatic relations on 18 August 1975* Algeria has an embassy in N'Djamena.", "* Chad has an embassy in Algiers.23 June 2005Both countries established diplomatic relations on 23 June 2005 when Angolian Ambassador to Chad with residence in Libreville (Gabon) Mr. Emílio Guerra presented his credentials to President Idriss Deby.18 October 1976Both countries established diplomatic relations on 18 October 19769 February 2015Both countries established diplomatic relations on 9 February 2015 when first Ambassador of Chad to Botswana, Mr. Mahamoud Bechir, presented his credentials to President Khama.", "* Chad has an embassy in Ouagadougou.6 December 1972Both countries established diplomatic relations on 6 December 1972 when first Ambassador of Chad to Burundi Mr. Alphonse M'Bainoungam, presented his credentials to the Chief of the Burundi state, Colonel Michel Micombero.1962Both countries established diplomatic relations in 1962* Cameroon has an embassy in N'Djamena.", "* Chad has an embassy in Yaoundé and a consulate in Garoua.29 February 1964Both countries established diplomatic relations on 29 February 1964 when has been accredited first Permanent Representative (Ambassador) of Chad to Central African Republic Mr. Thomas Keiro.", "* Central African Republic has an embassy in N'Djamena.", "* Chad has an embassy in Bangui.", "* Chad has an embassy in Kinshasa.13 February 1963Both countries established diplomatic relations on 13 February 1963 when has been appointed Mr. Simon Bilombo as Permanent Representative of the Republic of Congo to Chad.20 April 2009Both countries established diplomatic relations on 20 April 2009* Chad has an embassy in Cairo.", "* Egypt has an embassy in N'Djamena.", "* Chad has an embassy in Malabo.12 October 2021Both countries established diplomatic relations on 12 October 2021 when Ambassador of Eritrea to Chad with residence in Khartoum Mr. Issa Ahmed Issa, presented his credentials to Head of State, General Mahamat Idriss Deby Itno.21 October 1969Both countries established diplomatic relations on 21 October 1969 when the first Ambassador of Chad to Ethiopia, M. Abdurahman Musa, presented his credentials to Emperor Haile Selassie* Chad has an embassy in Addis Ababa.", "* Chad has an embassy in Libreville.31 August 2021Both countries established diplomatic relations on 31 August 202124 July 1967Both countries established diplomatic relations on 24 July 1967 when first Ghanaian Ambassador to Chad, with residence in Kinshasa, M. John Quashie has presented his credentials to President Tombalbaye29 August 1968Both countries established diplomatic relations on 29 August 1968 when Guinea's first Ambassador to Chad, Mr. Filly Cissoko, presented his credentials to President Tombolbaye15 November 1977Both countries established diplomatic relations on 15 November 1977* Chad has an embassy in Abidjan.", "* Côte d'Ivoire has an embassy in N'Djamena.", "* Chad is represented in Kenya through its embassy in Addis Ababa.See Chad-Libya relationsChadian-Libyan relations were ameliorated when Libyan-supported Idriss Déby unseated Habré on December 2.Gaddafi was the first head of state to recognize the new regime, and he also signed treaties of friendship and cooperation on various levels; but regarding the Aouzou Strip Déby followed his predecessor, declaring that if necessary he would fight to keep the strip out of Libya's hands.The Aouzou dispute was concluded for good on February 3, 1994, when the judges of the ICJ by a majority of 16 to 1 decided that the Aouzou Strip belonged to Chad.", "The court's judgement was implemented without delay, the two parties signing as early as April 4 an agreement concerning the practical modalities for the implementation of the judgement.", "Monitored by international observers, the withdrawal of Libyan troops from the Strip began on April 15 and was completed by May 10.The formal and final transfer of the Strip from Libya to Chad took place on May 30, when the sides signed a joint declaration stating that the Libyan withdrawal had been effected.", "* Chad has an embassy in Tripoli.", "* Libya has an embassy in N'Djamena.", "* The two countries maintain diplomatic relations.", "* Chad has an embassy in Bamako.", "* Chad has an embassy in Rabat.", "* Morocco has an embassy in N'Djamena.The two countries maintain diplomatic relations and Idriss Déby visited Mozambique in November 2016.25 October 2016Both countries established diplomatic relations on 25 October 2016 when has been accredited non-resident Ambassador of Chad to Namibia Mr. Ahmat Awad Sakine.", "* Chad is accredited to Namibia from its embassy in Pretoria, South Africa.", "* Namibia is accredited to Chad from its embassy in Kinshasa, DR Congo.", "* Chad has an embassy in Niamey.", "See Chad-Nigeria relationsNigeria's 1983 economic austerity campaign produced strains with neighboring states, including Chad.", "Nigeria expelled several hundred thousand foreign workers, mostly from its oil industry, which faced drastic cuts as a result of declining world oil prices.", "At least 30,000 of those expelled were Chadians.", "Despite these strains, however, Nigerians had assisted in the halting process of achieving stability in Chad, and both nations reaffirmed their intention to maintain close ties.", "* Chad has an embassy in Abuja and a consulate in Maiduguri.", "* Nigeria has an embassy in N'Djamena.9 December 1972Both countries established diplomatic relations on 9 December 1972 when Alphonse M'Bainoungam, ambassador of Chad to Zaire, presented his letters of credentials to Rwanda.", "* Chad has an embassy in Dakar.21 October 1994Both countries established diplomatic relations on 21 October 1994* Chad has an embassy in Pretoria.", "* South Africa has an embassy in N'Djamena.15 March 1961 See Chad-Sudan relationsBoth countries established diplomatic relations on 15 March 1961On December 24, 2005, Chad declared itself as in a \"state of belligerance\" with neighboring Sudan.", "The conflict in the border region of Darfur has become an increasingly bi-national affair as increasing numbers of Sudanese flee to refugee camps in Chad, and Sudanese government troops and militias cross the borders to strike at both these camps and specific ethnic groups.", "Although the Government of Chad and the Government of Sudan signed the Tripoli Agreement on February 8, 2006, officially ending hostilities, fighting continues.", "On August 11, 2006, Chad and Sudan resumed relations at the behest of Libyan leader Muammar Gaddafi.Chad broke diplomatic relations with Sudan at least twice in 2006 because it believed the Sudanese government was supporting Janjaweed and UFDC rebels financially and with arms.", "Two accords were signed, the Tripoli Accord, which was signed on February 8 and failed to end the fighting, and the more recently signed N'Djamena Agreement.", "On May 11, 2008, Sudan announced it was cutting diplomatic relations with Chad, claiming that it was helping rebels in Darfur to attack the Sudanese capital Khartoum.", "* Chad has an embassy in Khartoum and a consulate-general in Geneina.", "* Sudan has an embassy in N'Djamena.The two countries maintain diplomatic relations and Idriss Déby visited Kenya in November 2016.10 April 1985Both countries established diplomatic relations on 10 April 1985 when Ambassador of Chad Mr. Youssouf Nboudou Mbami presented his credentials to President of Togo.25 January 1968Both countries established diplomatic relations on 25 January 19688 September 1976Both countries established diplomatic relations on 8 September 1976 when Ambassador of Uganda Lt.-Col. Mohamadou Omoua Aziz has presented his credentials to President of Chad Malloum.", "* Zambia is represented in Chad through its embassy in Abuja, Nigeria.13 February 2023Both countries established diplomatic relations on 13 February 2023 when first Ambassador of Zimbabwe to Chad with residence in Khartoum Dr Emmanuel Bulukani Runganga Gumbo, presented his credentials to President of Transition, General Mahamat Idriss Deby Itno." ], [ "Americas", " Country Formal Relations BeganNotes24 May 1974Both countries established diplomatic relations on 24 May 1974* Argentina is accredited to Chad from its embassy in Abuja, Nigeria.", "* Chad does not have an accreditation to Argentina.", "8 October 1996Both countries established diplomatic relations on 8 October 1996* Brazil is accredited to Chad from its embassy in Yaoundé, Cameroon.", "* Chad does not have an accreditation to Brazil.February 1962Both countries established diplomatic relations in February 1962* Canada is accredited to Chad from its embassy in Khartoum, Sudan and has an honorary consulate in N'Djamena.", "* Chad has an embassy in Ottawa.26 September 2018Both countries established diplomatic relations on 26 September 201829 September 1988Both countries established diplomatic relations on 29 September 19889 June 1976Both countries established diplomatic relations on 9 June 1976* Chad is accredited to Cuba from its embassy in Washington, D.C., United States.", "* Cuba is accredited to Chad from its embassy in Niamey, Niger.25 February 1976See Chad–Mexico relationsChad and Mexico established diplomatic relations on 25 February 1976.In May 2002, Chadian Prime Minister Nagoum Yamassoum paid a visit to the Mexican city of Monterrey to attend the Monterrey Consensus conference.", "* Chad is accredited to Mexico from its embassy in Washington, D.C., United States.", "* Mexico is accredited to Chad from its embassy in Cairo, Egypt.24 September 2021Both countries established diplomatic relations on 24 September 202111 August 1960 See Chad–United States relationsBoth countries established diplomatic relations on 11 August 1960Embassy of Chad in Washington, D.C.The US embassy in N'Djamena, established at Chadian independence in 1960, was closed from the onset of the heavy fighting in the city in 1980 until the withdrawal of the Libyan forces at the end of 1981.It was reopened in January 1982.The U.S. Agency for International Development (USAID) and the U.S. Information Service (USIS) offices resumed activities in Chad in September 1983.The United States Department of State issued a travel advisory to U.S. citizens in 2009, recommending that citizens not affiliated with humanitarian efforts avoid all travel to eastern Chad and the Chad/Central African Republic border area due to insecurity caused by banditry, recent clashes between Chadian government and rebel forces, and political tension between Chad and Sudan.", "President Donald Trump issued a proclamation on September 24, 2017, suspending the entry of Chadian nationals to the United States.", "The proclamation claims that the government of Chad \"does not adequately share public-safety and terrorism-related information...\" On April 10, 2018, the US Government lifted travel restrictions on Chad.", "* Chad has an embassy in Washington, DC.", "* United States has an embassy in N'djamena.", "5 May 2005Both countries established diplomatic relations on 5 May 2005* Chad is accredited to Venezuela from its embassy in Washington, D.C, United States.", "* Venezuela does not have an accreditation to Chad." ], [ "Asia", "Despite centuries-old cultural ties to the Arab World, the Chadian Government maintained few significant ties to Arab states in North Africa or Southwest Asia in the 1980s.", "Chad had broken off relations with the State of Israel under former Chadian President François (Ngarta) Tombalbaye in September 1972.President Habré hoped to pursue closer relations with Arab states as a potential opportunity to break out of his Chad's post-imperial dependence on France, and to assert Chad's unwillingness to serve as an arena for superpower rivalries.", "In addition, as a northern Muslim, Habré represented a constituency that favored Afro-Arab solidarity, and he hoped Islam would provide a basis for national unity in the long term.", "For these reasons, he was expected to seize opportunities during the 1990s to pursue closer ties with the Arab World.", "In 1988, Chad recognized the State of Palestine, which maintains a mission in N'Djamena.", "In November 2018, President Deby visited Israel and announced his intention to restore diplomatic relations.", "Chad and Israel re-established diplomatic relations in January 2019.In February 2023, Chad opened an embassy in Israel.During the 1980s, Arab opinion on the Chadian-Libyan conflict over the Aouzou Strip was divided.", "Several Arab states supported Libyan territorial claims to the Strip, among the most outspoken of which was Algeria, which provided training for anti-Habré forces, although most recruits for its training programs were from Nigeria or Cameroon, recruited and flown to Algeria by Libya.", "Lebanon's Progressive Socialist Party also sent troops to support Qadhafi's efforts against Chad in 1987.In contrast, numerous other Arab states opposed the Libyan actions, and expressed their desire to see the dispute over the Aouzou Strip settled peacefully.", "By the end of 1987, Algiers and N'Djamena were negotiating to improve relations and Algeria helped mediate the end of the Aouzou Strip conflict Country Formal Relations BeganNotes26 December 2006Both countries established diplomatic relations on 26 December 2006.5 April 2004Both countries established diplomatic relations on 5 April 200410 December 1972Both countries established diplomatic relations on 10 December 1972* Chad is represented in Brunei through its embassy in Riyadh, Saudi Arabia.9 February 2010Both countries established diplomatic relations on 9 February 201028 November 1972See Chad–China relationsBoth countries established diplomatic relations on 28 November 1972, but China severed diplomatic relations with Chad in 1997 when the country resumed diplomatic ties with Taiwan.", "According to a joint communique signed by the two countries when they resumed diplomatic ties starting from August 6, 2006, Chad recognized there is only one China in the world and Taiwan is an inalienable part of the Chinese territory* Chad has an embassy in Beijing.", "* China has an embassy in N'Djamena.19 June 2014Both countries established diplomatic relations on 19 June 201418 October 1975See Chad–India relationsBoth countries established diplomatic relations on 18 October 1975* Chad has an embassy in New Delhi.", "* India is accredited to Chad from its high commission in Abuja, Nigeria and maintains an honorary consulate in N'Djamena.22 September 2016Both countries established diplomatic relations on 22 September 2016.19 July 1972Both countries established diplomatic relations on 19 July 197229 April 1973Both countries established diplomatic relations on 29 April 1973.10 January 1961See Chad–Israel relationsBoth countries established diplomatic relations on 10 January 1961, but diplomatic relations were broken on 28 November 1972 and re-established on 20 January 2019In November 2018, Chadian President Idriss Déby paid a visit to Israel.", "In January 2019 Israeli Prime Minister Benjamin Netanyahu paid a visit to Chad.", "During the visit, both nations re-established diplomatic relations since relations were cut in 1972.In February 2023, Chad opened an embassy in Israel.", "* Chad has an embassy in Tel Aviv.", "* Israel is accredited to Chad from its embassy in Dakar, Senegal1960Both countries established diplomatic relations in 1960January 1970Both countries established diplomatic relations in January 197021 July 1999Both countries established diplomatic relations on 21 July 199931 March 1970Both countries established diplomatic relations on 31 March 197011 January 1993Both countries established diplomatic relations on 11 January 1993The two countries maintain diplomatic relations.", "* Malaysia is represented in Chad through its High Commission in Abuja, Nigeria.3 April 2014Both countries established diplomatic relations on 3 April 20148 March 1969Both countries established diplomatic relations on 8 March 19691 December 1973Both countries established diplomatic relations on 1 December 1973* Pakistan is represented in Chad through its embassy in Sudan.", "* The State of Palestine is represented in Chad through its embassy in Bamako, Mali.22 September 1960Both countries established diplomatic relations on 22 September 196013 December 1972Both countries established diplomatic relations on 13 December 1972* Chad has an embassy in Doha.", "* Qatar has an embassy in N'Djamena.20 November 1972Both countries established diplomatic relations on 20 November 1972* Chad has an embassy in Riyadh and a consulate in Jeddah.", "* Saudi Arabia has an embassy in N'Djamena.25 September 2018Both countries established diplomatic relations on 25 September 20186 August 1961Both countries established diplomatic relations on 6 August 196116 August 1969Both countries established diplomatic relations on 16 August 1969See Chad–Taiwan relationsChad and Taiwan had relations from 1962 to 1972 when Chad first switched diplomatic recognition to the People's Republic of China.", "Chad then reestablished bilateral ties with Taiwan from 1997 to 2006.Since August 2006, Chad has granted diplomatic recognition to China.27 February 1993Both countries established diplomatic relations on 27 February 199328 September 1990Both countries established diplomatic relations on 28 September 199027 January 1970See Chad–Turkey relationsBoth countries established diplomatic relations on 27 January 1970* Chad has an embassy in Ankara.", "* Turkey has an embassy in N'Djamena.", "* Trade volume between the two countries was US$72.4 million in 2019 (Chadian exports/imports: 32.5/39.9 million USD).", "*There are direct flights from Istanbul to N'Djamena since December 12, 2013.4 October 1994Both countries established diplomatic relations on 4 October 19947 April 1973Both countries established diplomatic relations on 7 April 1973* Chad has an embassy in Abu Dhabi and a consulate-general in Dubai.", "* UAE has an embassy in N'Djamena.", "*UAE opened coordination office for foreign aid in Chad in August 2023.16 September 1994Both countries established diplomatic relations on 16 September 19945 October 1981Both countries established diplomatic relations on 5 October 198110 November 1970Both countries established diplomatic relations on 10 November 1970" ], [ "Europe", "Chad is officially non-aligned but has close relations with France, the former colonial power, which has about 1,200 troops stationed in the capital N'Djamena.", "It receives economic aid from countries of the European Community, the United States, and various international organizations.", "Libya supplies aid and has an ambassador resident in N'Djamena.", "Traditionally strong ties with the Western community have weakened over the past two years due to a dispute between the Government of Chad and the World Bank over how the profits from Chad's petroleum reserves are allocated.", "Although oil output to the West has resumed and the dispute has officially been resolved, resentment towards what the Déby administration considered foreign meddling lingers.", "Country Formal Relations BeganNotesAustria is represented in Chad through its embassy in Abuja, Nigeria.27 June 1961Both countries established diplomatic relations on 27 June 1961 when first Ambassador of Chad Mr. Adoum Aganaye presented his credentials to King of Belgium* Belgium is accredited to Chad from its embassy in Yaoundé, Cameroon and maintains an honorary consulate in N'Djamena.", "* Chad has an embassy in Brussels.14 January 2001Both countries established diplomatic relations on 20 August 200125 November 1994Both countries established diplomatic relations on 25 November 199410 October 1989Both countries established diplomatic relations on 10 October 198917 September 1999Both countries established diplomatic relations on 17 September 199918 September 2002Both countries established diplomatic relations on 18 September 20025 February 1967Both countries established diplomatic relations on 5 February 1967Denmark is represented in Chad through its embassy in Ouagadougou, Burkina Faso.27 September 2018Both countries established diplomatic relations on 27 September 201821 March 2007Both countries established diplomatic relations on 21 March 200712 August 1960See Chad–France relationsBoth countries established diplomatic relations on 12 August 1960France was Chad's most important foreign donor and patron for the first three decades following independence in 1960.At the end of the 1980s, economic ties were still strong, and France provided development assistance in the form of loans and grants.", "It was no longer Chad's leading customer for agricultural exports, but it continued to provide substantial military support.Chad remained a member of the African Financial Community, which linked the value of its currency, the CFA franc, to the French franc.", "French private and government investors owned a substantial portion of Chad's industrial and financial institutions, and the French treasury backed the Bank of Central African States, which served as the central bank for Chad and six other member nations.", "Chad's dependence on France declined slightly during Habré's tenure as president, in part because other foreign donors and investors returned as the war subsided and also because increased rainfall since 1985 improved food production.", "French official attitudes toward Chad had changed from the 1970s policies under the leadership of Giscard d'Estaing to those of the Mitterrand era of the 1980s.", "Economic, political, and strategic goals, which had emphasized maintaining French influence in Africa, exploiting Chad's natural resources, and bolstering francophone Africa's status as a bulwark against the spread of Soviet influence, had been replaced by nominally anticolonialist attitudes.", "The election in France of the Socialist government in 1981 had coincided with conditions of near-anarchy in Chad, leading France's Socialist Party to reaffirm its ideological stance against high-profile intervention in Africa.", "Hoping to avoid a confrontation with Libya, another important client state in the region, President Mitterrand limited French military involvement to a defense of the region surrounding N'Djamena in 1983 and 1984.Then, gradually increasing its commitment to reinforce Habré's presidency, France once again increased its military activity in Chad.", "* Chad has an embassy in Paris.", "* France has an embassy in N'djamena.11 August 1960Both countries established diplomatic relations on 11 August 1960* Chad has an embassy in Berlin.", "* Germany has an embassy in N'Djamena.13 September 1975Both countries established diplomatic relations on 13 September 1975 when first Ambassador of Greece to Chad, Mr. Statis Mitsopoulos presented his credentials to General Félix Malloum, Chadian Head of State28 November 1988Both countries established diplomatic relations on 28 November 19881 November 1972Both countries established diplomatic relations on 1 November 197214 April 2004Both countries established diplomatic relations on 14 April 200430 June 2000Both countries established diplomatic relations on 30 June 200013 February 1964Both countries established diplomatic relations on 13 February 1964 wnen the first Italian ambassador to Chad, Mr. Francesco Paolo Campanella, presented his credentials to the President27 May 2018Both countries established diplomatic relations on 27 May 2018.23 April 1996Both countries established diplomatic relations on 23 April 199626 June 2019Both countries established diplomatic relations on 26 June 2019 when accredited first Ambassador of Chad to Liechtenstein with recidence in Berlin Ms Mariam Ali Moussa10 August 1994Both countries established diplomatic relations on 10 August 199428 April 1964Both countries established diplomatic relations on 28 April 196420 March 2015Both countries established diplomatic relations on 20 March 20157 May 1962 See Chad–Netherlands relationsBoth countries established diplomatic relations on 7 May 1962 when accredited first Ambassador of Nerherlands to Chad (resident in Leopoldville) * Chad is accredited to Netherlands from its embassy in Brussels, Belgium.", "* Netherlands is accredited to Chad from its embassy in Khartoum, Sudan.13 October 1999Both countries established diplomatic relations on 13 October 199913 November 1995Both countries established diplomatic relations on 13 November 19955 January 1979Both countries established diplomatic relations on 5 January 1979* Chad is accredited to Poland from its embassy in Moscow, Russia.", "* Poland is accredited to Chad from its embassy in Tunis, Tunisia.4 May 1977Both countries established diplomatic relations on 4 May 197715 July 1969 See Chad–Romania relationsChad–Romania relations were established on July 15, 1969.However, neither country has an embassy in the other's capital, and although an agreement on trade was signed in 1969, followed by an agreement on economic and technical cooperation in 1971, , the volume of bilateral trade remained insignificant.In November 2007, Romania announced that they would deploy 120 troops to Chad and the Central African Republic in connection with a European Union peacekeeping mission there.", "Romania continued to condemn violence in Chad and blamed it on rebel groups.", "However, by mid-2008, Romanian defence minister Teodor Meleşcanu indicated that his country would not send further troops to the mission in Chad, stating that they had reached their limits and did not want involvement in a war theatre.Chad and Romania have almost identical flags.24 November 1964Both countries established diplomatic relations on 24 November 1964* Chad has an embassy in Moscow.", "* Russia has an embassy in N'Djamena.31 May 1964Both countries established diplomatic relations on 31 May 196420 April 2000Both countries established diplomatic relations on 20 April 20007 February 1975See Chad–Spain relationsBoth countries established diplomatic relations on 7 February 1975* Chad is accredited to Spain from its embassy in Paris, France.", "* Spain is accredited to Chad from its embassy in Yaoundé, Cameroon.3 August 1995Both countries established diplomatic relations on 3 August 199516 December 1963Both countries established diplomatic relations on 16 December 1963 when appointed first Ambassador of Switzerland to Chad (resident in Lagos) Mr. Giovanni Enrico Bucher* Chad has an embassy in Geneva accredited to Switzerland and the United Nations.", "* Switzerland has a cooperation office in N'Djamena.27 July 1993Both countries established diplomatic relations on 27 July 19939 December 1960Both countries established diplomatic relations on 9 December 1960" ], [ "Oceania", " Country Formal Relations BeganNotesAustralia is represented in Chad through its embassy in Paris, France.4 September 2015Both countries established diplomatic relations on 4 September 2015" ], [ "Membership of international organizations", "Chad belongs to the following international organizations:* United Nations and some of its specialized and related agencies* Organization for African Unity* Central African Customs and Economic Union (UDEAC)* African Financial Community (Franc Zone)* Agency for the Francophone Community* African, Caribbean and Pacific Group of States* African Development Bank* Central African States Development Bank* Economic and Monetary Union of Central African (CEMAC)* Economic Commission for Africa; G-77* International Civil Aviation Organization* International Red Cross and Red Crescent Movement* International Development Association* Islamic Development Bank* International Fund for Agricultural Development* International Finance Corporation* International Federation of the Red Cross and Red Crescent Societies* International Labour Organization* International Monetary Fund* Intelsat* Interpol* International Olympic Committee* International Telecommunication Union* International Trade Union Confederation* NAM* Organisation of Islamic Cooperation* Organisation for the Prohibition of Chemical Weapons* Universal Postal Union* World Confederation of Labour* World Intellectual Property Organization;* World Meteorological Organization;* World Tourism Organization* World Trade Organization" ], [ "See also", "* List of diplomatic missions in Chad* List of diplomatic missions of Chad" ], [ "References" ] ]

[ [ "Commentary" ], [ "Introduction", "'''Commentary''' or '''commentaries''' may refer to:" ], [ "Publications", "* ''Commentary'' (magazine), a U.S. public affairs journal, founded in 1945 and formerly published by the American Jewish Committee* Caesar's Commentaries (disambiguation), a number of works by or attributed to Julius Caesar* ''Commentaries'' of Ishodad of Merv, set of ninth-century Syriac treatises on the Bible* ''Commentaries on the Laws of England'', a 1769 treatise on the common law of England by Sir William Blackstone* ''Commentaries on Living'', a series of books by Jiddu Krishnamurti originally published in 1956, 1958 and 1960* ''Moralia in Job'', a sixth-century treatise by Saint Gregory* ''Commentary of Zuo'', one of the earliest Chinese works of narrative history, covering the period from 722 to 468 BCE* ''Commentaries'', a work attributed to Taautus" ], [ "Other uses", "* Published opinion piece material, in any of several forms:** An editorial, written by the editorial staff or board of a newspaper, magazine, or other periodical** Column (periodical), a regular feature of such a publication in which usually the same single writer offers advice, observation, or other commentary ** An op-ed, an opinion piece by an author unaffiliated with the publication** Letters to the editor, written by readers of such a publication** Posts made in the comments section of an online publication, serving a similar function to paper periodicals' letters to the editor* Commentary (philology), a line-by-line or even word-by-word explication (and usually translation) of a text* Audio commentary track for DVDs and Blu-Rays – an additional audio track that plays in real-time with the video material, and comments on that video* Sports commentary or play-by-play, a running description of a game or event in real time, usually during a live broadcast** Color commentary, supplementing play-by-play commentary, often filling in any time when play is not in progress* Atthakatha, commentaries on the Pāli Canon in Theravāda Buddhism* Criticism, the practice of judging the merits and faults of something or someone* ''Commentary!", "The Musical'', the musical commentary accompanying ''Dr.", "Horrible's Sing-Along Blog''* Commentary or narration, the words in a documentary film* Exegesis, a critical explanation or interpretation of a text, especially a religious text (e.g.", "a Bible commentary)* Literary criticism, the study, evaluation, and interpretation of literature** Close reading in literary criticism, the careful, sustained interpretation of a brief passage of text* Political criticism or political commentary, criticism that is specific of or relevant to politics** Public commentary received by governmental and other bodies, e.g.", "in response to proposals, reports, etc." ], [ "See also", "* Commentry, a place in central France* Comment (disambiguation)* List of biblical commentaries* Jewish commentaries on the Bible* ''Commentaire'', a French quarterly* Reaction video, commentaries in video format" ] ]

[ [ "Colloid" ], [ "Introduction", "SEM image of a colloid.|303x303pxA '''colloid''' is a mixture in which one substance consisting of microscopically dispersed insoluble particles is suspended throughout another substance.", "Some definitions specify that the particles must be dispersed in a liquid, while others extend the definition to include substances like aerosols and gels.", "The term '''colloidal suspension''' refers unambiguously to the overall mixture (although a narrower sense of the word ''suspension'' is distinguished from colloids by larger particle size).", "A colloid has a dispersed phase (the suspended particles) and a continuous phase (the medium of suspension).", "The dispersed phase particles have a diameter of approximately 1 nanometre to 1 micrometre.Some colloids are translucent because of the Tyndall effect, which is the scattering of light by particles in the colloid.", "Other colloids may be opaque or have a slight color.Colloidal suspensions are the subject of interface and colloid science.", "This field of study began in 1845 by Francesco Selmi and expanded by Michael Faraday and Thomas Graham, who coined the term ''colloid'' in 1861." ], [ "Classification of colloids", "Colloids can be classified as follows: Medium/phase Dispersed phase Gas Liquid Solid Dispersion medium Gas '''Liquid aerosol'''Examples: fog, clouds, condensation, mist, steam, hair sprays'''Solid aerosol'''Examples: smoke, ice cloud, atmospheric particulate matter Liquid'''Foam'''Example: whipped cream, shaving cream'''Emulsion or Liquid crystal'''Examples: milk, mayonnaise, hand cream, latex, , liquid biomolecular condensate'''Sol'''Examples: pigmented ink, sediment, precipitates, solid biomolecular condensate Solid'''Solid foam'''Examples: aerogel, floating soap, styrofoam, pumice'''Gel'''Examples: agar, gelatin, jelly, gel-like biomolecular condensate'''Solid sol'''Example: cranberry glassHomogeneous mixtures with a dispersed phase in this size range may be called ''colloidal aerosols'', ''colloidal emulsions'', ''colloidal suspensions'', ''colloidal foams'', ''colloidal dispersions'', or ''hydrosols''.File:Aerogel hand.jpg|AerogelFile:Jello Cubes.jpg|Jello cubesFile:Opaleszens Kolloid SiO2.jpg|Colloidal silica gel with light opalescenceFile:Crème Chantilly.jpg|Whipped creamFile:Dollop of hair gel.jpg|A dollop of hair gelFile:Cream in round container.jpg|Creams are semi-solid emulsions of oil and water.", "Oil-in-water creams are used for cosmetic purpose while water-in-oil creams for medicinal purposeFile:Why is the sky blue.jpg|Tyndall effect in an opalite:it scatters blue light making it appear blue from the side, but orange light shines through.opal is a gel in which water is dispersed in silica crystalsFile:Milk and straw.jpg|Milk - emulsion of liquid butterfat globules dispersed in waterFile:Mist - Ensay region3.jpg|Mist" ], [ "Hydrocolloids", "'''Hydrocolloids''' describe certain chemicals (mostly polysaccharides and proteins) that are colloidally dispersible in water.", "Thus becoming effectively \"soluble\" they change the rheology of water by raising the viscosity and/or inducing gelation.", "They may provide other interactive effects with other chemicals, in some cases synergistic, in others antagonistic.", "Using these attributes hydrocolloids are very useful chemicals since in many areas of technology from foods through pharmaceuticals, personal care and industrial applications, they can provide stabilization, destabilization and separation, gelation, flow control, crystallization control and numerous other effects.", "Apart from uses of the soluble forms some of the hydrocolloids have additional useful functionality in a dry form if after solubilization they have the water removed - as in the formation of films for breath strips or sausage casings or indeed, wound dressing fibers, some being more compatible with skin than others.", "There are many different types of hydrocolloids each with differences in structure function and utility that generally are best suited to particular application areas in the control of rheology and the physical modification of form and texture.", "Some hydrocolloids like starch and casein are useful foods as well as rheology modifiers, others have limited nutritive value, usually providing a source of fiber.The term hydrocolloids also refers to a type of dressing designed to lock moisture in the skin and help the natural healing process of skin to reduce scarring, itching and soreness.===Components===Hydrocolloids contain some type of gel-forming agent, such as sodium carboxymethylcellulose (NaCMC) and gelatin.", "They are normally combined with some type of sealant, i.e.", "polyurethane to 'stick' to the skin." ], [ "Colloid compared with solution", "A colloid has a dispersed phase and a continuous phase, whereas in a solution, the solute and solvent constitute only one phase.", "A solute in a solution are individual molecules or ions, whereas colloidal particles are bigger.", "For example, in a solution of salt in water, the sodium chloride (NaCl) crystal dissolves, and the Na+ and Cl− ions are surrounded by water molecules.", "However, in a colloid such as milk, the colloidal particles are globules of fat, rather than individual fat molecules.", "Because colloid is multiple phases, it has very different properties compared to fully mixed, continuous solution." ], [ "Interaction between particles", "The following forces play an important role in the interaction of colloid particles:*Excluded volume repulsion: This refers to the impossibility of any overlap between hard particles.", "*Electrostatic interaction: Colloidal particles often carry an electrical charge and therefore attract or repel each other.", "The charge of both the continuous and the dispersed phase, as well as the mobility of the phases are factors affecting this interaction.", "*van der Waals forces: This is due to interaction between two dipoles that are either permanent or induced.", "Even if the particles do not have a permanent dipole, fluctuations of the electron density gives rise to a temporary dipole in a particle.", "This temporary dipole induces a dipole in particles nearby.", "The temporary dipole and the induced dipoles are then attracted to each other.", "This is known as van der Waals force, and is always present (unless the refractive indexes of the dispersed and continuous phases are matched), is short-range, and is attractive.", "*Steric forces between polymer-covered surfaces or in solutions containing non-adsorbing polymer can modulate interparticle forces, producing an additional steric repulsive force (which is predominantly entropic in origin) or an attractive depletion force between them." ], [ "Sedimentation velocity", "268x268pxThe Earth’s gravitational field acts upon colloidal particles.", "Therefore, if the colloidal particles are denser than the medium of suspension, they will sediment (fall to the bottom), or if they are less dense, they will cream (float to the top).", "Larger particles also have a greater tendency to sediment because they have smaller Brownian motion to counteract this movement.The sedimentation or creaming velocity is found by equating the Stokes drag force with the gravitational force::where: is the Archimedean weight of the colloidal particles,: is the viscosity of the suspension medium,: is the radius of the colloidal particle,and is the sedimentation or creaming velocity.The mass of the colloidal particle is found using::where: is the volume of the colloidal particle, calculated using the volume of a sphere ,and is the difference in mass density between the colloidal particle and the suspension medium.By rearranging, the sedimentation or creaming velocity is::There is an upper size-limit for the diameter of colloidal particles because particles larger than 1 μm tend to sediment, and thus the substance would no longer be considered a colloidal suspension.The colloidal particles are said to be in sedimentation equilibrium if the rate of sedimentation is equal to the rate of movement from Brownian motion." ], [ "Preparation", "There are two principal ways to prepare colloids:* Dispersion of large particles or droplets to the colloidal dimensions by milling, spraying, or application of shear (e.g., shaking, mixing, or high shear mixing).", "* Condensation of small dissolved molecules into larger colloidal particles by precipitation, condensation, or redox reactions.", "Such processes are used in the preparation of colloidal silica or gold.=== Stabilization ===The stability of a colloidal system is defined by particles remaining suspended in solution and depends on the interaction forces between the particles.", "These include electrostatic interactions and van der Waals forces, because they both contribute to the overall free energy of the system.A colloid is stable if the interaction energy due to attractive forces between the colloidal particles is less than kT, where k is the Boltzmann constant and T is the absolute temperature.", "If this is the case, then the colloidal particles will repel or only weakly attract each other, and the substance will remain a suspension.If the interaction energy is greater than kT, the attractive forces will prevail, and the colloidal particles will begin to clump together.", "This process is referred to generally as aggregation, but is also referred to as flocculation, coagulation or precipitation.", "While these terms are often used interchangeably, for some definitions they have slightly different meanings.", "For example, coagulation can be used to describe irreversible, permanent aggregation where the forces holding the particles together are stronger than any external forces caused by stirring or mixing.", "Flocculation can be used to describe reversible aggregation involving weaker attractive forces, and the aggregate is usually called a ''floc''.", "The term precipitation is normally reserved for describing a phase change from a colloid dispersion to a solid (precipitate) when it is subjected to a perturbation.", "Aggregation causes sedimentation or creaming, therefore the colloid is unstable: if either of these processes occur the colloid will no longer be a suspension.Examples of a stable and of an unstable colloidal dispersion.Electrostatic stabilization and steric stabilization are the two main mechanisms for stabilization against aggregation.", "* Electrostatic stabilization is based on the mutual repulsion of like electrical charges.", "The charge of colloidal particles is structured in an electrical double layer, where the particles are charged on the surface, but then attract counterions (ions of opposite charge) which surround the particle.", "The electrostatic repulsion between suspended colloidal particles is most readily quantified in terms of the zeta potential.", "The combined effect of van der Waals attraction and electrostatic repulsion on aggregation is described quantitatively by the DLVO theory.", "A common method of stabilising a colloid (converting it from a precipitate) is peptization, a process where it is shaken with an electrolyte.", "* Steric stabilization consists absorbing a layer of a polymer or surfactant on the particles to prevent them from getting close in the range of attractive forces.", "The polymer consists of chains that are attached to the particle surface, and the part of the chain that extends out is soluble in the suspension medium.", "This technique is used to stabilize colloidal particles in all types of solvents, including organic solvents.A combination of the two mechanisms is also possible (electrosteric stabilization).276x276pxA method called gel network stabilization represents the principal way to produce colloids stable to both aggregation and sedimentation.", "The method consists in adding to the colloidal suspension a polymer able to form a gel network.", "Particle settling is hindered by the stiffness of the polymeric matrix where particles are trapped, and the long polymeric chains can provide a steric or electrosteric stabilization to dispersed particles.", "Examples of such substances are xanthan and guar gum.=== Destabilization ===Destabilization can be accomplished by different methods:*Removal of the electrostatic barrier that prevents aggregation of the particles.", "This can be accomplished by the addition of salt to a suspension to reduce the Debye screening length (the width of the electrical double layer) of the particles.", "It is also accomplished by changing the pH of a suspension to effectively neutralise the surface charge of the particles in suspension.", "This removes the repulsive forces that keep colloidal particles separate and allows for aggregation due to van der Waals forces.", "Minor changes in pH can manifest in significant alteration to the zeta potential.", "When the magnitude of the zeta potential lies below a certain threshold, typically around ± 5mV, rapid coagulation or aggregation tends to occur.", "*Addition of a charged polymer flocculant.", "Polymer flocculants can bridge individual colloidal particles by attractive electrostatic interactions.", "For example, negatively charged colloidal silica or clay particles can be flocculated by the addition of a positively charged polymer.", "*Addition of non-adsorbed polymers called depletants that cause aggregation due to entropic effects.Unstable colloidal suspensions of low-volume fraction form clustered liquid suspensions, wherein individual clusters of particles sediment if they are more dense than the suspension medium, or cream if they are less dense.", "However, colloidal suspensions of higher-volume fraction form colloidal gels with viscoelastic properties.", "Viscoelastic colloidal gels, such as bentonite and toothpaste, flow like liquids under shear, but maintain their shape when shear is removed.", "It is for this reason that toothpaste can be squeezed from a toothpaste tube, but stays on the toothbrush after it is applied.===Monitoring stability===Measurement principle of multiple light scattering coupled with vertical scanningThe most widely used technique to monitor the dispersion state of a product, and to identify and quantify destabilization phenomena, is multiple light scattering coupled with vertical scanning.", "This method, known as turbidimetry, is based on measuring the fraction of light that, after being sent through the sample, it backscattered by the colloidal particles.", "The backscattering intensity is directly proportional to the average particle size and volume fraction of the dispersed phase.", "Therefore, local changes in concentration caused by sedimentation or creaming, and clumping together of particles caused by aggregation, are detected and monitored.", "These phenomena are associated with unstable colloids.Dynamic light scattering can be used to detect the size of a colloidal particle by measuring how fast they diffuse.", "This method involves directing laser light towards a colloid.", "The scattered light will form an interference pattern, and the fluctuation in light intensity in this pattern is caused by the Brownian motion of the particles.", "If the apparent size of the particles increases due to them clumping together via aggregation, it will result in slower Brownian motion.", "This technique can confirm that aggregation has occurred if the apparent particle size is determined to be beyond the typical size range for colloidal particles.===Accelerating methods for shelf life prediction===The kinetic process of destabilisation can be rather long (up to several months or years for some products).", "Thus, it is often required for the formulator to use further accelerating methods to reach reasonable development time for new product design.", "Thermal methods are the most commonly used and consist of increasing temperature to accelerate destabilisation (below critical temperatures of phase inversion or chemical degradation).", "Temperature affects not only viscosity, but also interfacial tension in the case of non-ionic surfactants or more generally interactions forces inside the system.", "Storing a dispersion at high temperatures enables to simulate real life conditions for a product (e.g.", "tube of sunscreen cream in a car in the summer), but also to accelerate destabilisation processes up to 200 times.Mechanical acceleration including vibration, centrifugation and agitation are sometimes used.", "They subject the product to different forces that pushes the particles / droplets against one another, hence helping in the film drainage.", "Some emulsions would never coalesce in normal gravity, while they do under artificial gravity.", "Segregation of different populations of particles have been highlighted when using centrifugation and vibration." ], [ "As a model system for atoms", "In physics, colloids are an interesting model system for atoms.", "Micrometre-scale colloidal particles are large enough to be observed by optical techniques such as confocal microscopy.", "Many of the forces that govern the structure and behavior of matter, such as excluded volume interactions or electrostatic forces, govern the structure and behavior of colloidal suspensions.", "For example, the same techniques used to model ideal gases can be applied to model the behavior of a hard sphere colloidal suspension.", "Phase transitions in colloidal suspensions can be studied in real time using optical techniques, and are analogous to phase transitions in liquids.", "In many interesting cases optical fluidity is used to control colloid suspensions." ], [ "Crystals", "A colloidal crystal is a highly ordered array of particles that can be formed over a very long range (typically on the order of a few millimeters to one centimeter) and that appear analogous to their atomic or molecular counterparts.", "One of the finest natural examples of this ordering phenomenon can be found in precious opal, in which brilliant regions of pure spectral color result from close-packed domains of amorphous colloidal spheres of silicon dioxide (or silica, SiO2).", "These spherical particles precipitate in highly siliceous pools in Australia and elsewhere, and form these highly ordered arrays after years of sedimentation and compression under hydrostatic and gravitational forces.", "The periodic arrays of submicrometre spherical particles provide similar arrays of interstitial voids, which act as a natural diffraction grating for visible light waves, particularly when the interstitial spacing is of the same order of magnitude as the incident lightwave.Thus, it has been known for many years that, due to repulsive Coulombic interactions, electrically charged macromolecules in an aqueous environment can exhibit long-range crystal-like correlations with interparticle separation distances, often being considerably greater than the individual particle diameter.", "In all of these cases in nature, the same brilliant iridescence (or play of colors) can be attributed to the diffraction and constructive interference of visible lightwaves that satisfy Bragg’s law, in a matter analogous to the scattering of X-rays in crystalline solids.The large number of experiments exploring the physics and chemistry of these so-called \"colloidal crystals\" has emerged as a result of the relatively simple methods that have evolved in the last 20 years for preparing synthetic monodisperse colloids (both polymer and mineral) and, through various mechanisms, implementing and preserving their long-range order formation." ], [ "In biology", "Colloidal phase separation is an important organising principle for compartmentalisation of both the cytoplasm and nucleus of cells into '''biomolecular condensates'''—similar in importance to compartmentalisation via lipid bilayer membranes, a type of liquid crystal.", "The term biomolecular condensate has been used to refer to clusters of macromolecules that arise via liquid-liquid or liquid-solid phase separation within cells.", "Macromolecular crowding strongly enhances colloidal phase separation and formation of biomolecular condensates." ], [ "In the environment", "Colloidal particles can also serve as transport vectorof diverse contaminants in the surface water (sea water, lakes, rivers, fresh water bodies) and in underground water circulating in fissured rocks(e.g.", "limestone, sandstone, granite).", "Radionuclides and heavy metals easily sorb onto colloids suspended in water.", "Various types of colloids are recognised: inorganic colloids (e.g.", "clay particles, silicates, iron oxy-hydroxides), organic colloids (humic and fulvic substances).", "When heavy metals or radionuclides form their own pure colloids, the term \"''eigencolloid''\" is used to designate pure phases, i.e., pure Tc(OH)4, U(OH)4, or Am(OH)3.Colloids have been suspected for the long-range transport of plutonium on the Nevada Nuclear Test Site.", "They have been the subject of detailed studies for many years.", "However, the mobility of inorganic colloids is very low in compacted bentonites and in deep clay formationsbecause of the process of ultrafiltration occurring in dense clay membrane.The question is less clear for small organic colloids often mixed in porewater with truly dissolved organic molecules.In soil science, the colloidal fraction in soils consists of tiny clay and humus particles that are less than 1μm in diameter and carry either positive and/or negative electrostatic charges that vary depending on the chemical conditions of the soil sample, i.e.", "soil pH." ], [ "Intravenous therapy", "Colloid solutions used in intravenous therapy belong to a major group of volume expanders, and can be used for intravenous fluid replacement.", "Colloids preserve a high colloid osmotic pressure in the blood, and therefore, they should theoretically preferentially increase the intravascular volume, whereas other types of volume expanders called crystalloids also increase the interstitial volume and intracellular volume.", "However, there is still controversy to the actual difference in efficacy by this difference, and much of the research related to this use of colloids is based on fraudulent research by Joachim Boldt.", "Another difference is that crystalloids generally are much cheaper than colloids." ], [ "References" ] ]

[ [ "Chinese" ], [ "Introduction", " '''Chinese''' may refer to:* Something related to China* Chinese people, people identified with China, through nationality, citizenship, and/or ethnicity**Han Chinese, East Asian ethnic group native to China.", "**''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation** List of ethnic groups in China, people of various ethnicities in contemporary China** Ethnic minorities in China, people of non-Han Chinese ethnicities in modern China** Ethnic groups in Chinese history, people of various ethnicities in historical China** Nationals of the People's Republic of China** Nationals of the Republic of China ** Overseas Chinese, Chinese people residing outside the territories of mainland China, Hong Kong, Macau, and Taiwan* Sinitic languages, the major branch of the Sino-Tibetan language family** Chinese language, a group of related languages spoken predominantly in China, sharing a written script (Chinese characters in traditional and simplified forms)*** Standard Chinese, the standard form of Mandarin Chinese in mainland China, similar to forms of Mandarin Chinese in Taiwan and Singapore*** Varieties of Chinese, topolects grouped under Chinese languages*** Written Chinese, writing scripts used for Chinese languages****Chinese characters, logograms used for the writing of East Asian languages* Chinese cuisine, styles of food originating from China or their derivatives*\"Chinese\", a song about take out meals by Lily Allen from ''It's Not Me, It's You''" ], [ "See also", "* Chinese citizen (disambiguation)* Tang Chinese (disambiguation)*" ] ]

[ [ "Riding shotgun" ], [ "Introduction", "\"'''Riding shotgun'''\" was a phrase used to describe the bodyguard who rides alongside a stagecoach driver, typically armed with a break-action shotgun, called a coach gun, to ward off bandits or hostile Native Americans.", "In modern use, it refers to the practice of sitting alongside the driver in a moving vehicle.", "The coining of this phrase dates to 1905 at the latest." ], [ "Etymology", "The expression \"riding shotgun\" is derived from \"shotgun messenger\", a colloquial term for \"express messenger\", when stagecoach travel was popular during the American Wild West and the Colonial period in Australia.", "The person rode alongside the driver.", "The first known use of the phrase \"riding shotgun\" was in the 1905 novel ''The Sunset Trail'' by Alfred Henry Lewis.", "It was later used in print and especially film depiction of stagecoaches and wagons in the Old West in danger of being robbed or attacked by bandits.", "A special armed employee of the express service using the stage for transportation of bullion or cash would sit beside the driver, carrying a short shotgun (or alternatively a rifle), to provide an armed response in case of threat to the cargo, which was usually a strongbox.", "Absence of an armed person in that position often signaled that the stage was not carrying a strongbox, but only passengers." ], [ "Historical examples", "===Tombstone, Arizona Territory===On the evening of March 15, 1881, a Kinnear & Company stagecoach carrying US$26,000 in silver bullion () was en route from the boom town of Tombstone, Arizona Territory to Benson, Arizona, the nearest freight terminal.", "Bob Paul, who had run for Pima County Sheriff and was contesting the election he lost due to ballot-stuffing, was temporarily working once again as the Wells Fargo shotgun messenger.", "He had taken the reins and driver's seat in Contention City because the usual driver, a well-known and popular man named Eli \"Budd\" Philpot, was ill. Philpot was riding shotgun.Near Drew's Station, just outside Contention City, a man stepped into the road and commanded them to \"Hold!\"", "Three cowboys attempted to rob the stage.", "Paul, in the driver's seat, fired his shotgun and emptied his revolver at the robbers, wounding a cowboy later identified as Bill Leonard in the groin.", "Philpot, riding shotgun, and passenger Peter Roerig, riding in the rear dickey seat, were both shot and killed.", "The horses spooked and Paul wasn't able to bring the stage under control for almost a mile, leaving the robbers with nothing.", "Paul, who normally rode shotgun, later said he thought the first shot killing Philpot had been meant for him.When Wyatt Earp first arrived in Tombstone in December 1879, he initially took a job as a stagecoach shotgun messenger for Wells Fargo, guarding shipments of silver bullion.", "When Earp was appointed Pima County Deputy Sheriff on July 27, 1881, his brother Morgan Earp took over his job.===Historical weapon===When Wells, Fargo & Co. began regular stagecoach service from Tipton, Missouri to San Francisco, California in 1858, they issued shotguns to its drivers and guards for defense along the perilous 2,800 mile route.", "The guard was called a shotgun messenger and they were issued a Coach gun, typically a 10-gauge or 12-gauge, short, double-barreled shotgun." ], [ "Modern usage", "More recently, the term has been applied to a game, usually played by groups of friends to determine who rides beside the driver in a car.", "Typically, this involves claiming the right to ride shotgun by being the first person to call out \"shotgun\" when everyone is in view of the vehicle; in some regions, calling shotgun too early disqualifies one from the game.", "Variable rules may apply such as users needing to be within view of the car, or having to be on the same level as the car (the same parking lot, garage, etc.).", "The game creates an environment that is fair by forgetting and leaving out most seniority except that parents and significant others automatically get shotgun, and this meanwhile leaves out any conflicts that may have previously occurred when deciding who gets to ride shotgun." ], [ "See also", "* Coach gun* Drive-by shooting* Shotgun messenger" ], [ "References" ] ]

[ [ "Cooking" ], [ "Introduction", "A man cooking in a restaurant kitchen, Morocco'''Cooking''', also known as '''cookery''' or professionally as the '''culinary arts''', is the art, science and craft of using heat to make food more palatable, digestible, nutritious, or safe.", "Cooking techniques and ingredients vary widely, from grilling food over an open fire, to using electric stoves, to baking in various types of ovens, reflecting local conditions.Types of cooking also depend on the skill levels and training of the cooks.", "Cooking is done both by people in their own dwellings and by professional cooks and chefs in restaurants and other food establishments.Preparing food with heat or fire is an activity unique to humans.", "Archeological evidence of cooking fires from at least 300,000 years ago exists, but some estimate that humans started cooking up to 2 million years ago.The expansion of agriculture, commerce, trade, and transportation between civilizations in different regions offered cooks many new ingredients.", "New inventions and technologies, such as the invention of pottery for holding and boiling of water, expanded cooking techniques.", "Some modern cooks apply advanced scientific techniques to food preparation to further enhance the flavor of the dish served." ], [ "History", "Pots being heated with a wood-burning fire in South IndiaPhylogenetic analysis suggests that early hominids may have adopted cooking 1 million to 2 million years ago.", "of burnt bone fragments and plant ashes from the Wonderwerk Cave in South Africa has provided evidence supporting control of fire by early humans by 1 million years ago.", "In his seminal work ''Catching Fire: How Cooking Made Us Human'', Richard Wrangham suggested that evolution of bipedalism and a large cranial capacity meant that early ''Homo habilis'' regularly cooked food.", "However, unequivocal evidence in the archaeological record for the controlled use of fire begins at 400,000 BCE, long after ''Homo erectus''.", "Archaeological evidence from 300,000 years ago, in the form of ancient hearths, earth ovens, burnt animal bones, and flint, are found across Europe and the Middle East.", "The oldest evidence (via heated fish teeth from a deep cave) of controlled use of fire to cook food by archaic humans was dated to ~780,000 years ago.", "Anthropologists think that widespread cooking fires began about 250,000 years ago when hearths first appeared.Recently, the earliest hearths have been reported to be at least 790,000 years old.Communication between the Old World and the New World in the Columbian Exchange influenced the history of cooking.", "The movement of foods across the Atlantic from the New World, such as potatoes, tomatoes, maize, beans, bell pepper, chili pepper, vanilla, pumpkin, cassava, avocado, peanut, pecan, cashew, pineapple, blueberry, sunflower, chocolate, gourds, and squash, had a profound effect on Old World cooking.", "The movement of foods across the Atlantic from the Old World, such as cattle, sheep, pigs, wheat, oats, barley, rice, apples, pears, peas, chickpeas, green beans, mustard, and carrots, similarly changed New World cooking.In the 17th and 18th centuries, food was a classic marker of identity in Europe.", "In the 19th-century \"Age of Nationalism\", cuisine became a defining symbol of national identity.The Industrial Revolution brought mass-production, mass-marketing, and standardization of food.", "Factories processed, preserved, canned, and packaged a wide variety of foods, and processed cereals quickly became a defining feature of the American breakfast.", "In the 1920s, freezing methods, cafeterias, and fast food restaurants emerged." ], [ "Ingredients", "Most ingredients in cooking are derived from living organisms.", "Vegetables, fruits, grains and nuts as well as herbs and spices come from plants, while meat, eggs, and dairy products come from animals.", "Mushrooms and the yeast used in baking are kinds of fungi.", "Cooks also use water and minerals such as salt.", "Cooks can also use wine or spirits.Naturally occurring ingredients contain various amounts of molecules called ''proteins'', ''carbohydrates'' and ''fats''.", "They also contain water and minerals.", "Cooking involves a manipulation of the chemical properties of these molecules.===Carbohydrates===Carbohydrates include the common sugar, sucrose (table sugar), a disaccharide, and such simple sugars as glucose (made by enzymatic splitting of sucrose) and fructose (from fruit), and starches from sources such as cereal flour, rice, arrowroot and potato.The interaction of heat and carbohydrate is complex.", "Long-chain sugars such as starch tend to break down into more digestible simpler sugars.", "If the sugars are heated so that all water of crystallisation is driven off, caramelization starts, with the sugar undergoing thermal decomposition with the formation of carbon, and other breakdown products producing caramel.", "Similarly, the heating of sugars and proteins causes the Maillard reaction, a basic flavor-enhancing technique.An emulsion of starch with fat or water can, when gently heated, provide thickening to the dish being cooked.", "In European cooking, a mixture of butter and flour called a roux is used to thicken liquids to make stews or sauces.", "In Asian cooking, a similar effect is obtained from a mixture of rice or corn starch and water.", "These techniques rely on the properties of starches to create simpler mucilaginous saccharides during cooking, which causes the familiar thickening of sauces.", "This thickening will break down, however, under additional heat.===Fats===Doughnuts frying in oilTypes of fat include vegetable oils, animal products such as butter and lard, as well as fats from grains, including maize and flax oils.", "Fats are used in a number of ways in cooking and baking.", "To prepare stir fries, grilled cheese or pancakes, the pan or griddle is often coated with fat or oil.", "Fats are also used as an ingredient in baked goods such as cookies, cakes and pies.", "Fats can reach temperatures higher than the boiling point of water, and are often used to conduct high heat to other ingredients, such as in frying, deep frying or sautéing.", "Fats are used to add flavor to food (e.g., butter or bacon fat), prevent food from sticking to pans and create a desirable texture.Fats are one of the three main macronutrient groups in human diet, along with carbohydrates and proteins, and the main components of common food products like milk, butter, tallow, lard, salt pork, and cooking oils.", "They are a major and dense source of food energy for many animals and play important structural and metabolic functions, in most living beings, including energy storage, waterproofing, and thermal insulation.", "The human body can produce the fat it requires from other food ingredients, except for a few essential fatty acids that must be included in the diet.", "Dietary fats are also the carriers of some flavor and aroma ingredients and vitamins that are not water-soluble.===Proteins===Edible animal material, including muscle, offal, milk, eggs and egg whites, contains substantial amounts of protein.", "Almost all vegetable matter (in particular legumes and seeds) also includes proteins, although generally in smaller amounts.", "Mushrooms have high protein content.", "Any of these may be sources of essential amino acids.", "When proteins are heated they become denatured (unfolded) and change texture.", "In many cases, this causes the structure of the material to become softer or more friable – meat becomes ''cooked'' and is more friable and less flexible.", "In some cases, proteins can form more rigid structures, such as the coagulation of albumen in egg whites.", "The formation of a relatively rigid but flexible matrix from egg white provides an important component in baking cakes, and also underpins many desserts based on meringue.Water is often used to cook foods such as noodles.===Water===Cooking often involves water, and water-based liquids.", "These can be added in order to immerse the substances being cooked (this is typically done with water, stock or wine).", "Alternatively, the foods themselves can release water.", "A favorite method of adding flavor to dishes is to save the liquid for use in other recipes.", "Liquids are so important to cooking that the name of the cooking method used is often based on how the liquid is combined with the food, as in steaming, simmering, boiling, braising and blanching.", "Heating liquid in an open container results in rapidly increased evaporation, which concentrates the remaining flavor and ingredients; this is a critical component of both stewing and sauce making.===Vitamins and minerals===Vegetables contain important vitamins and mineralsVitamins and minerals are required for normal metabolism; and what the body cannot manufacture itself must come from external sources.", "Vitamins come from several sources including fresh fruit and vegetables (Vitamin C), carrots, liver (Vitamin A), cereal bran, bread, liver (B vitamins), fish liver oil (Vitamin D) and fresh green vegetables (Vitamin K).", "Many minerals are also essential in small quantities including iron, calcium, magnesium, sodium chloride and sulfur; and in very small quantities copper, zinc and selenium.", "The micronutrients, minerals, and vitamins in fruit and vegetables may be destroyed or eluted by cooking.", "Vitamin C is especially prone to oxidation during cooking and may be completely destroyed by protracted cooking.", "The bioavailability of some vitamins such as thiamin, vitamin B6, niacin, folate, and carotenoids are increased with cooking by being freed from the food microstructure.", "Blanching or steaming vegetables is a way of minimizing vitamin and mineral loss in cooking." ], [ "Methods", "There are many methods of cooking, most of which have been known since antiquity.", "These include baking, roasting, frying, grilling, barbecuing, smoking, boiling, steaming and braising.", "A more recent innovation is microwaving.", "Various methods use differing levels of heat and moisture and vary in cooking time.", "The method chosen greatly affects the result because some foods are more appropriate to some methods than others.", "Some major hot cooking techniques include:green peppers in a skillet.", ";Roasting:Roasting – Barbecuing – Grilling/Broiling – Rotisserie – Searing;Baking:Baking – Baking Blind – Flashbaking;Boiling:Boiling – Blanching – Braising – Coddling – Double steaming – Infusion – Poaching – Pressure cooking – Simmering – Smothering – Steaming – Steeping – Stewing – Stone boiling – Vacuum flask cooking;Frying:Fry – Air frying — Deep frying – Gentle frying – Hot salt frying – Hot sand frying – Pan frying – Pressure frying – Sautéing – Shallow frying – Stir frying – Vacuum frying;Steaming:Steaming works by boiling water continuously, causing it to vaporise into steam; the steam then carries heat to the nearby food, thus cooking the food.", "By many it is considered a healthy form of cooking, holding nutrients within the vegetable or meat being cooked.", ": En papillote – The food is put into a pouch and then baked, allowing its own moisture to steam the food.", ";Smoking:Smoking is the process of flavoring, cooking, or preserving food by exposing it to smoke from burning or smoldering material, most often wood." ], [ "Health and safety", "=== Indoor air pollution ===As of 2021, over 2.6 billion people cook using open fires or inefficient stoves using kerosene, biomass, and coal as fuel.", "These cooking practices use fuels and technologies that produce high levels of household air pollution, causing 3.8 million premature deaths annually.", "Of these deaths, 27% are from pneumonia, 27% from ischaemic heart disease, 20% from chronic obstructive pulmonary disease, 18% from stroke, and 8% from lung cancer.", "Women and young children are disproportionately affected, since they spend the most time near the hearth.=== Security while cooking ===Hazards while cooking can include* Unseen slippery surfaces (such as from oil stains, water droplets, or items that have fallen on the floor)* Cuts; about a third of the US's estimated annual 400,000 knife injuries are kitchen-related.", "* Burns or firesTo prevent those injuries there are protections such as cooking clothing, anti-slip shoes, fire extinguisher and more.===Food safety===Cooking can prevent many foodborne illnesses that would otherwise occur if raw food is consumed.", "When heat is used in the preparation of food, it can kill or inactivate harmful organisms, such as bacteria and viruses, as well as various parasites such as tapeworms and ''Toxoplasma gondii''.", "Food poisoning and other illness from uncooked or poorly prepared food may be caused by bacteria such as pathogenic strains of ''Escherichia coli'', ''Salmonella typhimurium'' and ''Campylobacter'', viruses such as noroviruses, and protozoa such as ''Entamoeba histolytica''.", "Bacteria, viruses and parasites may be introduced through salad, meat that is uncooked or done rare, and unboiled water.The sterilizing effect of cooking depends on temperature, cooking time, and technique used.", "Some food spoilage bacteria such as ''Clostridium botulinum'' or ''Bacillus cereus'' can form spores that survive boiling, which then germinate and regrow after the food has cooled.", "This makes it unsafe to reheat cooked food more than once.Cooking increases the digestibility of many foods which are inedible or poisonous when raw.", "For example, raw cereal grains are hard to digest, while kidney beans are toxic when raw or improperly cooked due to the presence of phytohaemagglutinin, which is inactivated by cooking for at least ten minutes at .Food safety depends on the safe preparation, handling, and storage of food.", "Food spoilage bacteria proliferate in the \"Danger zone\" temperature range from , food therefore should not be stored in this temperature range.", "Washing of hands and surfaces, especially when handling different meats, and keeping raw food separate from cooked food to avoid cross-contamination, are good practices in food preparation.", "Foods prepared on plastic cutting boards may be less likely to harbor bacteria than wooden ones.", "Washing and disinfecting cutting boards, especially after use with raw meat, poultry, or seafood, reduces the risk of contamination.===Effects on nutritional content of food===A raw tomato sauce with olives, celery, spinach and walnuts on zucchini noodles.Proponents of raw foodism argue that cooking food increases the risk of some of the detrimental effects on food or health.", "They point out that during cooking of vegetables and fruit containing vitamin C, the vitamin elutes into the cooking water and becomes degraded through oxidation.", "Peeling vegetables can also substantially reduce the vitamin C content, especially in the case of potatoes where most vitamin C is in the skin.", "However, research has shown that in the specific case of carotenoids a greater proportion is absorbed from cooked vegetables than from raw vegetables.Sulforaphane, a glucosinolate breakdown product, is present in vegetables such as broccoli, and is mostly destroyed when the vegetable is boiled.", "Although there has been some basic research on how sulforaphane might exert beneficial effects in vivo, there is no high-quality evidence for its efficacy against human diseases.The United States Department of Agriculture has studied retention data for 16 vitamins, 8 minerals, and alcohol for approximately 290 foods across various cooking methods.===Carcinogens===Chicken, pork and bacon-wrapped corn cooking in a barbecue smoker.", "Barbecuing and smoking generate carcinogens.In a human epidemiological analysis by Richard Doll and Richard Peto in 1981, diet was estimated to cause a large percentage of cancers.", "Studies suggest that around 32% of cancer deaths may be avoidable by changes to the diet.", "Some of these cancers may be caused by carcinogens in food generated during the cooking process, although it is often difficult to identify the specific components in diet that serve to increase cancer risk.Several studies published since 1990 indicate that cooking meat at high temperature creates heterocyclic amines (HCAs), which are thought to increase cancer risk in humans.", "Researchers at the National Cancer Institute found that human subjects who ate beef rare or medium-rare had less than one third the risk of stomach cancer than those who ate beef medium-well or well-done.", "While avoiding meat or eating meat raw may be the only ways to avoid HCAs in meat fully, the National Cancer Institute states that cooking meat below creates \"negligible amounts\" of HCAs.", "Also, microwaving meat before cooking may reduce HCAs by 90% by reducing the time needed for the meat to be cooked at high heat.", "Nitrosamines are found in some food, and may be produced by some cooking processes from proteins or from nitrites used as food preservatives; cured meat such as bacon has been found to be carcinogenic, with links to colon cancer.", "Ascorbate, which is added to cured meat, however, reduces nitrosamine formation.Baking, grilling or broiling food, especially starchy foods, until a toasted crust is formed generates significant concentrations of acrylamide.", "This discovery in 2002 led to international health concerns.", "Subsequent research has however found that it is not likely that the acrylamides in burnt or well-cooked food cause cancer in humans; Cancer Research UK categorizes the idea that burnt food causes cancer as a \"myth\"." ], [ "Scientific aspects", "The scientific study of cooking has become known as molecular gastronomy.", "This is a subdiscipline of food science concerning the physical and chemical transformations that occur during cooking.Important contributions have been made by scientists, chefs and authors such as Hervé This (chemist), Nicholas Kurti (physicist), Peter Barham (physicist), Harold McGee (author), Shirley Corriher (biochemist, author), Robert Wolke (chemist, author.)", "It is different for the application of scientific knowledge to cooking, that is \"molecular cooking\"( (for the technique) or \"molecular cuisine\" (for a culinary style), for which chefs such as Raymond Blanc, Philippe and Christian Conticini, Ferran Adria, Heston Blumenthal, Pierre Gagnaire (chef).Chemical processes central to cooking include hydrolysis (in particular beta elimination of pectins, during the thermal treatment of plant tissues), pyrolysis, and glycation reactions wrongly named Maillard reactions.Cooking foods with heat depends on many factors: the specific heat of an object, thermal conductivity, and (perhaps most significantly) the difference in temperature between the two objects.", "Thermal diffusivity is the combination of specific heat, conductivity and density that determines how long it will take for the food to reach a certain temperature." ], [ "Home-cooking and commercial cooking", "A restaurant kitchen in Munich, Germany (Haxnbauer restaurant)Home cooking has traditionally been a process carried out informally in a home or around a communal fire, and can be enjoyed by all members of the family, although in many cultures women bear primary responsibility.", "Cooking is also often carried out outside of personal quarters, for example at restaurants, or schools.", "Bakeries were one of the earliest forms of cooking outside the home, and bakeries in the past often offered the cooking of pots of food provided by their customers as an additional service.", "In the present day, factory food preparation has become common, with many \"ready-to-eat\" as well as \"ready-to-cook\" foods being prepared and cooked in factories and home cooks using a mixture of scratch made, and factory made foods together to make a meal.", "The nutritional value of including more commercially prepared foods has been found to be inferior to home-made foods.", "Home-cooked meals tend to be healthier with fewer calories, and less saturated fat, cholesterol and sodium on a per calorie basis while providing more fiber, calcium, and iron.", "The ingredients are also directly sourced, so there is control over authenticity, taste, and nutritional value.", "The superior nutritional quality of home-cooking could therefore play a role in preventing chronic disease.", "Cohort studies following the elderly over 10 years show that adults who cook their own meals have significantly lower mortality, even when controlling for confounding variables.", "\"Home-cooking\" may be associated with comfort food, and some commercially produced foods and restaurant meals are presented through advertising or packaging as having been \"home-cooked\", regardless of their actual origin.", "This trend began in the 1920s and is attributed to people in urban areas of the U.S. wanting homestyle food even though their schedules and smaller kitchens made cooking harder." ], [ "See also", "* Carryover cooking* Cookbook* Cooker* Cooking weights and measures* Culinary arts* Culinary profession* Cooking school* Dishwashing* Food and cooking hygiene* Food industry* Food preservation* Food writing* Foodpairing* Gourmet Museum and Library* High altitude cooking* International food terms* List of cooking appliances* List of cuisines* List of films about cooking* List of food preparation utensils* List of ovens* List of stoves* Scented water* Staple (cooking)" ], [ "References" ], [ "External links", "*" ] ]

[ [ "Card game" ], [ "Introduction", "''The Card Players'', 17th-century painting by Theodoor RomboutsA '''card game''' is any game that uses playing cards as the primary device with which the game is played, whether the cards are of a traditional design or specifically created for the game (proprietary).", "Countless card games exist, including families of related games (such as poker).", "A small number of card games played with traditional decks have formally standardized rules with international tournaments being held, but most are folk games whose rules may vary by region, culture, location or from circle to circle.Traditional card games are played with a ''deck'' or ''pack'' of playing cards which are identical in size and shape.", "Each card has two sides, the ''face'' and the ''back''.", "Normally the backs of the cards are indistinguishable.", "The faces of the cards may all be unique, or there can be duplicates.", "The composition of a deck is known to each player.", "In some cases several decks are shuffled together to form a single ''pack'' or ''shoe''.", "Modern card games usually have bespoke decks, often with a vast amount of cards, and can include number or action cards.", "This type of game is generally regarded as part of the board game hobby.Games using playing cards exploit the fact that cards are individually identifiable from one side only, so that each player knows only the cards they hold and not those held by anyone else.", "For this reason card games are often characterized as games of chance or \"imperfect information\"—as distinct from games of strategy or perfect information, where the current position is fully visible to all players throughout the game.", "Many games that are not generally placed in the family of card games do in fact use cards for some aspect of their play.Some games that are placed in the card game genre involve a board.", "The distinction is that the play in a card game chiefly depends on the use of the cards by players (the board is a guide for scorekeeping or for card placement), while board games (the principal non-card game genre to use cards) generally focus on the players' positions on the board, and use the cards for some secondary purpose." ], [ "History", "=== 14th and 15th centuries ===Despite the presence of playing cards in Europe being recorded from around 1370, it is not until 1408 that the first card game is described in a document about the exploits of two card sharps; although it is evidently very simple, the game is not named.", "In fact the earliest games to be mentioned by name are Gleek, Ronfa and Condemnade, the latter being the game played by the aforementioned card cheats.", "All three are recorded during the 15th century, along with Karnöffel, first mentioned in 1426 and which is still played in several forms today, including Bruus, Knüffeln, Kaiserspiel and Styrivolt.Since the arrival of trick-taking games in Europe in the late 14th century, there have only been two major innovations.", "The first was the introduction of trump cards with the power to beat all cards in other suits.", "Such cards were initially called ''trionfi'' and first appeared with the advent of Tarot cards in which there is a separate, permament trump suit comprising a number of picture cards.", "The first known example of such cards was ordered by the Duke of Milan around 1420 and included 16 trumps with images of Greek and Roman gods.", "Thus games played with Tarot cards appeared very early on and spread to most parts of Europe with the notable exceptions of the British Isles, the Iberian Peninsula, and the Balkans.", "However, we do not know the rules of the early Tarot games; the earliest detailed description in any language being those published by the Abbé de Marolles in Nevers in 1637.The concept of trumps was sufficiently powerful that it was soon transferred to games played with far cheaper ordinary packs of cards, as opposed to expensive Tarot cards.", "The first of these was Triomphe, the name simply being the French equivalent of the Italian ''trionfi''.", "Although not testified before 1538, its first rules were written by a Spaniard who left his native country for Milan in 1509 never to return; thus the game may date to the late 15th century.", "Others games that may well date to the 15th century are Pochen – the game of ''Bocken'' or ''Boeckels'' being attested in Strasbourg in 1441 – and Thirty-One, which is first mentioned in a French translation of a 1440 sermon by the Italian, Saint Bernadine, the name actually referring to two different card games: one like Pontoon and one like Commerce.=== 16th century ===In the 16th century printed documents replace handwritten sources and card games become a popular topic with preachers, autobiographists and writers in general.", "A key source of the games in vogue in France and Europe at that time is François Rabelais, whose fictional character ''Gargantua'' played no less than 30 card games, many of which are recognisable.", "They include: Aluette, Bête, Cent, Coquimbert, Coucou, Flush or Flux, Gé (Pairs), Gleek, Lansquenet, Piquet, Post and Pair, Primero, Ronfa, Triomphe, Sequence, Speculation, Tarot and Trente-et-Un; possibly Rams, Mouche and Brandeln as well.", "Girolamo Cardano also provides invaluable information including the earliest rules of Trappola.", "Among the most popular were the games of Flusso and Primiera, which originated in Italy and spread throughout Europe, becoming known in England as Flush and Primero.", "In Britain the earliest known European fishing game was recorded in 1522.Another first was Losing Loadum, noted by Florio in 1591, which is the earliest known English point-trick game.", "In Scotland, the game of Mawe, testified in the 1550s, evolved from a country game into one played at the royal Scottish court, becoming a favourite of James VI.", "The ancestor of Cribbage – a game called Noddy – is mentioned for the first time in 1589, \"Noddy\" being the Knave turned for trump at the start of play.=== 17th century ===The 17th century saw an upsurge in the number of new games being reported as well as the first sets of rules, those for Piquet appearing in 1632 and Reversis in 1634.The first French games compendium, ''La Maison Académique'', appeared in 1654 and it was followed in 1674 by Charles Cotton's ''The Compleat Gamester'', although an earlier manuscript of games by Francis Willughby was written sometime between 1665 and 1670.Cotton records the first rules for the classic English games of Cribbage, a descendant of Noddy, and Whist, a development of English Trump or Ruff ('ruff' then meaning 'rob') in which four players were dealt 12 cards each and the dealer 'robbed' from the remaining stock of 4 cards.Piquet was a two-player, trick-taking game that originated in France, probably in the 16th century and was initially played with 36 cards before, around 1690, the pack reduced to the 32 cards that gives the Piquet pack its name.", "Reversis is a reverse game in which players avoid taking tricks and appears to be an Italian invention that came to France around 1600 and spread rapidly to other countries in Europe.In the mid-17th century, a certain game named after Cardinal Mazarin, prime minister to King Louis XIV, became very popular at the French royal court.", "Called Hoc Mazarin, it had three phases, the final one of which evolved into a much simpler game called Manille that was renamed Comète on the appearance of Halley's Comet in 1682.In Comète the aim is to be first to shed all one's hand cards to sequences laid out in rows on the table.", "However, there are certain cards known as 'stops' or ''hocs'': cards that end a sequence and give the one who played it the advantage of being able to start a new sequence.", "This concept spread to other 17th and 18th century games including Poque, Comete, Emprunt, Manille, Nain Jaune and Lindor, all except Emprunt being still played in some form today.It was the 17th century that saw the second of the two great innovations being introduced into trick-taking games: the concept of bidding.", "This first emerged in the Spanish game of Ombre, an evolution of Triomphe that \"in its time, was the most successful card game ever invented.\"", "Ombre's origins are unclear and obfuscated by the existence of a game called Homme or Bête in France, ''ombre'' and ''homme'' being respectively Spanish and French for 'man'.", "In Ombre, the player who won the bidding became the \"Man\" and played alone against the other two.", "The game spread rapidly across Europe, spawning variants for different numbers of players and known as Quadrille, Quintille, Médiateur and Solo.", "Quadrille went on to become highly fashionable in England during the 18th century and is mentioned several times, for example, in Jane Austen's ''Pride and Prejudice''.The first rules of any game in the German language were those for Rümpffen published in 1608 and later expanded in several subsequent editions.", "In addition, the first German games compendium, ''Palamedes Redivivus'' appeared in 1678, containing the rules for Hoick (Hoc), Ombre, Picquet (sic), Rümpffen and Thurnspiel.=== 18th century ===The evolution of card games continued apace, with notable national games emerging like Briscola and Tressette (Italy), Schafkopf (Bavaria), Jass (Switzerland), Mariage, the ancestor of Austria's Schnapsen and Germany's Sixty-Six, and Tapp Tarock, the progenitor of most modern central European Tarot games.", "Whist spread to the continent becoming very popular in the north and west.", "In France, Comet appeared, a game that later evolved into Nain Jaune and the Victorian game of Pope Joan." ], [ "Types", "Preferans, a trick-taking card game version popular in CroatiaCard games may be classified in different ways: by their objective, by the equipment used (e.g.", "number of cards and type of suits), by country of origin or by mechanism (how the game is played).", "Parlett and McLeod predominantly group cards games by mechanism of which there are five categories: outplay, card exchange, hand comparison, layout and a miscellaneous category that includes combat and compendium games.", "These are described in the following sections." ], [ "Outplay games", "Easily the largest category of games in which players have a hand of cards and must play them out to the table.", "Play ends when players have played all their cards.===Trick-taking games===Trick-taking games are the largest category of outplay games.", "Players typically receive an equal number of cards and a trick involves each player playing a card face up to the table – the rules of play dictating what cards may be played and who wins the trick.There are two main types of trick-taking game with different objectives.", "Both are based on the play of multiple tricks, in each of which each player plays a single card from their hand, and based on the values of played cards one player wins or \"takes\" the trick.", "In plain-trick games the aim is to win a number of tricks, a specific trick or as many tricks as possible, without regard to the actual cards.", "In point-trick games, the number of tricks is immaterial; what counts is the value, in points, of the cards captured.==== Plain-trick games ====Many common Anglo-American games fall into the category of plain-trick games.", "The usual objective is to take the most tricks, but variations taking all tricks, making as few tricks (or penalty cards) as possible or taking an exact number of tricks.", "Bridge, Whist and Spades are popular examples.", "Hearts, Black Lady and Black Maria are examples of reverse games in which the aim is to avoid certain cards.", "Plain-trick games may be divided into the following 11 groups:* '''Whist group.'''", "A standard Whist pack is used with cards ranking in their natural order and four players playing in partnerships of two.", "Usually a trump suit is nominated through turning a card or bidding and the aim is to win as many tricks as possible.", "* '''No trump games'''.", "As above but there is no trump suit.", "* '''Put group'''.", "In Put, tricks are won by the highest card regardless of suit.", "Treys are usually highest.", "* '''Last trick group'''.", "The player who makes the last trick wins (or loses) the hand.", "* '''Trump group'''.", "Either trump games in which fewer cards are dealt (e.g.", "5) or in which there are chosen suits.", "* '''Ombre group'''.", "Ombre introduced one of the two most significant features in the history of card games: bidding.", "Other common characteristics of this family are 3 matadors and a talon of undealt cards.", "* '''Boston group'''.", "Games of the Boston group are played like Whist, but players form alliances of two or three players depending on the outcome of bidding.", "* '''Auction Whist group'''.", "Auction or Bid Whist games involved fixed partnerships and an auction to determine the contract to be played.", "* '''Preference group'''.", "Games of the Préférence family are typically for three players who 10 cards each from a 32-card pack and bid to play alone against the other two.", "* '''Exact bidding group'''.", "Players bid the exact number of tricks they expect to take and must achieve that to win.", "* '''Multi-trick group'''.", "Mostly Oriental games in which several cards may be led to a trick at once.", "However, some European games of the trump group, such as Bruus, also include this feature.==== Point-trick games ====Point-trick games are all European or of European origin and include the Tarot card games.", "Individual cards have specific point values and the objective is usually to amass the majority of points by taking tricks, especially those with higher value cards.", "There are around nine main groups:* '''Tarot games'''.", "All Tarot games use Tarot cards for their original purpose of playing games and are either French- or Spanish-suited.", "The tarots form a special trump suit and the counting cards are the highest, second highest and lowest trumps along with the court cards.", "There are usually bonuses for certain feats or card combinations and most games have multiple contracts which the players may bid for.", "Notable examples include German Cego, Austrian Tarock, French Tarot and Italian Minchiate.", "* '''Manille group.'''", "A small group of mainly French and Spanish games originating in \"Malille\" characterised by the top card being the 9 in Spanish games or the 10 in Belgian and French games.", "Additional counters are the AKQJ.", "* '''Couillon group.'''", "A small group from the Benelux countries in which the counters and highest cards are the ace (4), king (3), queen (2) and jack (1).", "A typical member is Luxembourgisch Konter a Matt.", "* '''Trappola group.'''", "This family is virtually extinct.", "Its progenitor, Trappola, was a Venetian game that emerged in the 1500s and was played with a special pack that is still available from Piatnik today.", "The counters are the ace (6), king (5), knight (4) and jack (3).", "There were bonuses for certain trick-winning feats.", "* '''All Fours group.'''", "Based on the old English game of All Fours in which there were game points for High (highest trump), Low (lowest trump), Jack (of trumps) and Game (most card points).", "Surviving members of the group include American Pitch, British Phat and Irish Don.", "* '''Ace–ten games'''.", "The ace–ten family includes most of the national games of Europe including German Skat, French Belote, Dutch Klaberjass, Austrian Schnapsen, Spanish Tute, Swiss Jass, Portuguese Sueca, Italian Briscola and Czech Mariáš.", "Pinochle is an American example of French or Swiss origin.", "Ace–ten games may be further subdivided into the Schafkopf group, marriage group (which includes the Jass group), the Sedma group and the German Tarok group (which includes American games like frog and six-bid solo.", "* '''Tresette group.'''", "Tressette is an Italian game with the odd card ranking of 32AKQJ7654.Aces count 1 point, treys, deuces and courts are worth point each.", "Most are Italian variants of Tressette, but Les Quatre Sept is played in Canada.", "* '''Reverse games'''.", "Historically the most significant was Reversis, now rarely played.", "The best known reverse game today is Black Lady albeit often misnamed after its predecessor, Hearts, thanks to Microsoft.", "Reverse games often feature in compendium games.", "* '''Miscellaneous games'''.", "These include small families of Oriental games such as the King-Ten-Five group, in which the counters are the kings and tens (10 each) and fives (5), and Picture group, in which the AKQJT are worth 1 point each and in which Elfern is the only Western example.", "Of historical interest are Gleek and Penneech, while Cucco is one played with a special Cucco pack.=== Beating games ===In beating games the idea is to beat the card just played if possible, otherwise it must be picked up, either alone or together with other cards, and added to the hand.", "In many beating games the objective is to shed all one's cards, in which case they are also \"shedding games\".", "Well known examples include Crazy Eights and Mau Mau.===Adding games===This is a small group whose ancestor is Noddy, now extinct, but which generated the far more interesting games of Costly Colours and Cribbage.", "Players play in turn and add the values of the cards as they go.", "The aim is to reach or avoid certain totals and also to score for certain combinations.===Fishing games=== In fishing games, cards from the hand are played against cards in a layout on the table, capturing table cards if they match.", "Fishing games are popular in many nations, including China, where there are many diverse fishing games.", "Scopa is considered one of the national card games of Italy.", "Cassino is the only fishing game to be widely played in English-speaking countries.", "Zwicker has been described as a \"simpler and jollier version of Cassino\", played in Germany.", "Tablanet (tablić) is a fishing-style game popular in Balkans.===Matching games===The object of a matching (or sometimes \"melding\") game is to acquire particular groups of matching cards before an opponent can do so.", "In Rummy, this is done through drawing and discarding, and the groups are called melds.", "Mahjong is a very similar game played with tiles instead of cards.", "Non-Rummy examples of match-type games generally fall into the \"fishing\" genre and include the children's games Go Fish and Old Maid.=== War group ===In games of the war group, also called \"catch and collect games\" or \"accumulating games\", the object is to acquire all cards in the deck.", "Examples include most War type games, and games involving slapping a discard pile such as Slapjack.", "Egyptian Ratscrew has both of these features.=== Climbing games ===Climbing games are an Oriental family in which the idea is to play a higher card or combination of cards that the one just played.", "Alternatively a player must pass or may choose to pass even if able to beat.", "The sole Western example is the game of President, which is probably derived from an Asian game." ], [ "Card exchange games", "Card exchange games form another large category in which players exchange a card or cards from their hands with table cards or with other players with the aim, typically, of collecting specific cards or card combinations.", "Games of the rummy family are the best known.===Draw and discard group ===In these games players draw a card from stock, make a move if possible or desired, and then discard a card to a discard pile.", "Almost all the games of this group are in the rummy family, but Golf is a non-rummy example.=== Commerce group ===As the name might suggest, players exchange hand cards with a common pool of cards on the table.", "Examples include Schwimmen, Kemps.", "James Bond and Whisky Poker.", "They originated in the old European games of Thirty-One and Commerce.=== Cuckoo group ===A very old round game played in different forms in different countries.", "Players are dealt just one card and may try and swap it with a neighbour to avoid having the lowest card or, sometimes, certain penalty cards.", "The old French game is Coucou and its later English cousin is Ranter Go Round, also called Chase the Ace and Screw Your Neighbour.", "A family of such games played with special cards includes Italian Cucù, Scandinavian Gnav, Austrian Hexenspiel and German Vogelspiel.=== Quartet group ===Games involving collecting sets of cards, the best known of which is Happy Families.", "Highly successful is its German equivalent, Quartett, which may be played with a Skat pack, but is much more commonly played with proprietary packs.=== Card passing group ===Games involving passing cards to your neighbours.", "The classic game is Old Maid which may, however, be derived from German Black Peter and related to the French game of Vieux Garçon.", "Pig, with its variations of Donkey and Spoons, is also popular." ], [ "Layout games", "=== Patience or solitaire games ===Most patience or card solitaire games are designed to be played by one player, but some are designed for two or more players to compete.==== Single player patiences or solitaires ====Patience games originated in northern Europe and were designed for a single player, hence its subsequent North American name of solitaire.", "Most games begin with a specific layout of cards, called a tableau, and the object is then either to construct a more elaborate final layout, or to clear the tableau and/or the draw pile or stock by moving all cards to one or more discard or foundation piles.==== Competitive patiences ====In competitive patiences, two or more players compete to be first to complete a patience or solitaire-like tableau.", "Some use a common layout; in others each player has a separate layout.", "Popular examples include Spite and Malice, Racing Demon or Nerts, Spit, Speed and Russian Bank.=== Connecting games ===The most common of these is Card Dominoes also known as Fan Tan or Parliament in which the idea is to build the four suits in sequence from a central card (the 7 in 52-card games or the Unter in 32-card packs).", "The winner is the first out and the loser the last left in holding cards." ], [ "Hand comparison games", "Hand comparison games, also called comparing card games, are mostly gambling games that use cards.", "Players lay their initial stakes, are dealt cards, may or may not be able to exchange or add to them, and may or may not be able to raise their stakes, and the outcome is decided by some form of comparison of card values or combinations.", "The main groups are vying and banking games.", "A smaller mainly Oriental group are partition games in which players divide their hands before comparing.===Vying games===Vying games, are those in which players bet or \"vie\" on who has the best hand.", "The player with the best combination of hand cards in a \"showdown\", or the player able to bluff the others into folding, wins the hand.", "Easily the best known of the group around the world is Poker, which itself is a family of games with over 100 variants.", "Other examples include English Brag and the old Basque game of Mus.", "Most may be classified as gambling games and, while they may involve skill in terms of bluffing and memorising and assessing odds, they involve little or no card playing skill.====Poker games====Poker is a family of gambling games in which players bet into a pool, called the pot, the value of which changes as the game progresses that the value of the hand they carry will beat all others according to the ranking system.", "Variants largely differ on how cards are dealt and the methods by which players can improve a hand.", "For many reasons, including its age and its popularity among Western militaries, it is one of the most universally known card games in existence.=== Banking games ===These are gambling games played for money or chips in which players compete, not against one another, but against a banker.", "They are commonly played in casinos, but many have become domesticised, played at home for sweets, matchsticks or points.", "In casino games, the banker will have a 'house advantage' that ensures a profit for the casino.", "Popular casino games include Blackjack and Baccarat, while Pontoon is a cousin of Blackjack that emerged from the trenches of the First World War to become a popular British family game." ], [ "Miscellaneous games", "These games do not fit into any of the foregoing categories.", "The only traditional games in this group are the compendium games, which date back at least 200 years, and Speculation, a 19th century trading game.", "=== Compendium games ===Compendium games consist of a sequence of different contracts played in succession.", "A common pattern is for a number of reverse deals to be played, in which the aim is to avoid certain cards, followed by a final contract which is a domino-type game.", "Examples include: Barbu, Herzeln, Lorum and Rosbiratschka.", "In other games, such as Quodlibet and Rumpel, there is a range of widely varying contracts.=== Combat games ===A new genre not recorded before 1970, most of which use proprietary cards of the collectible card game type (see below).", "The earliest and best known is Magic: The Gathering." ], [ "Card games by objective", "Another broad way of classifying card games is by objective.", "There are four main types as well as a handful of games that have miscellaneous objectives.=== Capturing games ===In these games the objective is to capture cards or to avoid capturing them.", "These break down into the following:* ''Most cards''.", "The aim is to capture as many cards as possible.", "Most plain trick games fall into this group.", "* ''Fewest cards.''", "Common in compendium games, otherwise rare.", "Often occurs as a contract within a game known as a Misère, Bettel, Null or Nolo.", "* ''Exact number of cards''.", "To win games of the exact bidding group a player must take the exact number of tricks bid.", "* ''Most points''.", "In point-trick games and most fishing games, the aim is to capture the most points in cards.", "* ''Fewest points''.", "Some or all cards incur penalty points and so the aim is to capture as few points as possible.", "* ''Exact points''.", "A small group in which players aim to score a specific number of points e.g.", "Differenzler Jass.", "* ''Most or fewest points''.", "In some Jass games e.g.", "Molotov, the aim is to secure either the most or fewest points, leaving the player in the middle as the loser.", "* ''Win last trick''.", "In games like Tuppen, the player who takes the last trick wins; all earlier tricks are irrelevant.", "Some games also have a bonus or extra points for winning the last trick or winning it with a specific card.", "* ''Lose last trick''.", "In a few games, e.g.", "Krypkille, the aim is to lose the last trick.", "* ''Mixed objectives''.", "Some games, e.g.", "Kaiser, have both positive and negative point cards.===Shedding games===In a shedding game, also called an accumulating game, players start with a hand of cards, and the object of the game is to be the first player to discard all cards from one's hand.", "Common shedding games include Crazy Eights (commercialized by Mattel as Uno) and Daihinmin.", "Some matching-type games are also shedding-type games; some variants of Rummy such as Paskahousu, Phase 10, Rummikub, the bluffing game I Doubt It, and the children's games Musta Maija and Old Maid, fall into both categories.===Combination games ===In many games, the aim is to form combinations of cards: by addition, by matching sets or forming sequences.", "All Rummy games are based on the last two principles, although in the basic variants, the end objective is to shed cards which makes them shedding games (see above).", "However, meld scoring variants such as Canasta or Rommé are true combination games.===Comparing games===Comparing card games are those where hand values are compared to determine the winner, also known as \"vying\" or \"showdown\" games.", "Poker, blackjack, mus, and baccarat are examples of comparing card games.", "As seen, nearly all of these games are designed as gambling games." ], [ "Drinking games", "Drinking card games are drinking games using cards, in which the object in playing the game is either to drink or to force others to drink.", "Many games are ordinary card games with the establishment of \"drinking rules\"; President, for instance, is virtually identical to Daihinmin but with additional rules governing drinking.", "Poker can also be played using a number of drinks as the wager.", "Another game often played as a drinking game is Toepen, quite popular in the Netherlands.", "Some card games are designed specifically to be played as drinking games." ], [ "Proprietary games", "These are card games played with a dedicated deck.", "Many other card games have been designed and published on a commercial or amateur basis.", "In a few cases, the game uses the standard 52-card deck, but the object is unique.", "In Eleusis, for example, players play single cards, and are told whether the play was legal or illegal, in an attempt to discover the underlying rules made up by the dealer.Most of these games however typically use a specially made deck of cards designed specifically for the game (or variations of it).", "The decks are thus usually proprietary, but may be created by the game's players.", "Uno, Phase 10, Set, and 1000 Blank White Cards are popular dedicated-deck card games; 1000 Blank White Cards is unique in that the cards for the game are designed by the players of the game while playing it; there is no commercially available deck advertised as such.===Collectible card games (CCGs)===Collectible card games (CCG) are proprietary playing card games.", "CCGs are games of strategy between two or more players.", "Each player has their own deck constructed from a very large pool of unique cards in the commercial market.", "The cards have different effects, costs, and art.", "New card sets are released periodically and sold as starter decks or booster packs.", "Obtaining the different cards makes the game a collectible card game, and cards are sold or traded on the secondary market.", "''Magic: The Gathering'', ''Pokémon'', and ''Yu-Gi-Oh!''", "are well-known collectible card games.===Living card games (LCGs)===Living card games (LCGs) are similar to collectible card games (CCGs), with their most distinguishing feature being a fixed distribution method, which breaks away from the traditional collectible card game format.", "While new cards for CCGs are usually sold in the form of starter decks or booster packs (the latter being often randomized), LCGs thrive on a model that requires players to acquire one core set in order to play the game, which players can further customize by acquiring extra sets or expansions featuring new content in the form of cards or scenarios.", "No randomization is involved in the process, thus players that get the same sets or expansions will get the exact same content.", "The term was popularized by Fantasy Flight Games (FFG) and mainly applies to its products, however some tabletop gaming companies can be seen using a very similar model.===Simulation card games===A deck of either customised dedicated cards or a standard deck of playing cards with assigned meanings is used to simulate the actions of another activity, for example card football." ], [ "Fictional card games", "Many games, including card games, are fabricated by science fiction authors and screenwriters to distance a culture depicted in the story from present-day Western culture.", "They are commonly used as filler to depict background activities in an atmosphere like a bar or rec room, but sometimes the drama revolves around the play of the game.", "Some of these games become real card games as the holder of the intellectual property develops and markets a suitable deck and ruleset for the game, while others lack sufficient descriptions of rules, or depend on cards or other hardware that are infeasible or physically impossible." ], [ "Typical structure of card games", "===Number and association of players===''The Card Players'', 1895 by Paul CézanneHistorically, card games such as whist and contract bridge were opportunities for quiet socializing, as shown in this 1930s magic lantern slide photo taken in Seattle, Washington.Any specific card game imposes restrictions on the number of players.", "The most significant dividing lines run between one-player games and two-player games, and between two-player games and multi-player games.", "Card games for one player are known as ''solitaire'' or ''patience'' card games.", "(See list of solitaire card games.)", "Generally speaking, they are in many ways special and atypical, although some of them have given rise to two- or multi-player games such as Spite and Malice.In card games for two players, usually not all cards are distributed to the players, as they would otherwise have perfect information about the game state.", "Two-player games have always been immensely popular and include some of the most significant card games such as piquet, bezique, sixty-six, klaberjass, gin rummy and cribbage.", "Many multi-player games started as two-player games that were adapted to a greater number of players.", "For such adaptations a number of non-obvious choices must be made beginning with the choice of a game orientation.One way of extending a two-player game to more players is by building two teams of equal size.", "A common case is four players in two fixed partnerships, sitting crosswise as in whist and contract bridge.", "Partners sit opposite to each other and cannot see each other's hands.", "If communication between the partners is allowed at all, then it is usually restricted to a specific list of permitted signs and signals.", "17th-century French partnership games such as triomphe were special in that partners sat next to each other and were allowed to communicate freely so long as they did not exchange cards or play out of order.Another way of extending a two-player game to more players is as a ''cut-throat'' or ''individual'' game, in which all players play for themselves, and win or lose alone.", "Most such card games are ''round games'', i.e.", "they can be played by any number of players starting from two or three, so long as there are enough cards for all.For some of the most interesting games such as ombre, tarot and skat, the associations between players change from hand to hand.", "Ultimately players all play on their own, but for each hand, some game mechanism divides the players into two teams.", "Most typically these are ''solo games'', i.e.", "games in which one player becomes the soloist and has to achieve some objective against the others, who form a team and win or lose all their points jointly.", "But in games for more than three players, there may also be a mechanism that selects two players who then have to play against the others.===Direction of play===The players of a card game normally form a circle around a table or other space that can hold cards.", "The ''game orientation'' or ''direction of play'', which is only relevant for three or more players, can be either clockwise or counterclockwise.", "It is the direction in which various roles in the game proceed.", "(In real-time card games, there may be no need for a direction of play.)", "Most regions have a traditional direction of play, such as:* Counterclockwise in most of Asia and in Latin America.", "* Clockwise in North America and Australia.Europe is roughly divided into a clockwise area in the north and a counterclockwise area in the south.", "The boundary runs between England, Ireland, Netherlands, Germany, Austria (mostly), Slovakia, Ukraine and Russia (clockwise) and France, Switzerland, Spain, Italy, Slovenia, Balkans, Hungary, Romania, Bulgaria, Greece and Turkey (counterclockwise).Games that originate in a region with a strong preference are often initially played in the original direction, even in regions that prefer the opposite direction.", "For games that have official rules and are played in tournaments, the direction of play is often prescribed in those rules.===Determining who deals===Most games have some form of asymmetry between players.", "The roles of players are normally expressed in terms of the ''dealer'', i.e.", "the player whose task it is to shuffle the cards and distribute them to the players.", "Being the dealer can be a (minor or major) advantage or disadvantage, depending on the game.", "Therefore, after each played hand, the deal normally passes to the next player according to the game orientation.As it can still be an advantage or disadvantage to be the first dealer, there are some standard methods for determining who is the first dealer.", "A common method is by cutting, which works as follows.", "One player shuffles the deck and places it on the table.", "Each player lifts a packet of cards from the top, reveals its bottom card, and returns it to the deck.", "The player who reveals the highest (or lowest) card becomes dealer.", "In the case of a tie, the process is repeated by the tied players.", "For some games such as whist this process of cutting is part of the official rules, and the hierarchy of cards for the purpose of cutting (which need not be the same as that used otherwise in the game) is also specified.", "But in general, any method can be used, such as tossing a coin in case of a two-player game, drawing cards until one player draws an ace, or rolling dice.===Hands, rounds and games===A ''hand'', also called a ''deal'', is a unit of the game that begins with the dealer shuffling and dealing the cards as described below, and ends with the players scoring and the next dealer being determined.", "The set of cards that each player receives and holds in his or her hands is also known as that player's hand.The hand is over when the players have finished playing their hands.", "Most often this occurs when one player (or all) has no cards left.", "The player who sits after the dealer in the direction of play is known as eldest hand (or in two-player games as elder hand) or forehand.", "A ''game round'' consists of as many hands as there are players.", "After each hand, the deal is passed on in the direction of play, i.e.", "the previous eldest hand becomes the new dealer.", "Normally players score points after each hand.", "A game may consist of a fixed number of rounds.", "Alternatively it can be played for a fixed number of points.", "In this case it is over with the hand in which a player reaches the target score.===Shuffling===Shuffling is the process of bringing the cards of a pack into a random order.", "There are a large number of techniques with various advantages and disadvantages.", "''Riffle shuffling'' is a method in which the deck is divided into two roughly equal-sized halves that are bent and then released, so that the cards interlace.", "Repeating this process several times randomizes the deck well, but the method is harder to learn than some others and may damage the cards.", "The ''overhand shuffle'' and the ''Hindu shuffle'' are two techniques that work by taking batches of cards from the top of the deck and reassembling them in the opposite order.", "They are easier to learn but must be repeated more often.", "A method suitable for small children consists in spreading the cards on a large surface and moving them around before picking up the deck again.", "This is also the most common method for shuffling tiles such as dominoes.For casino games that are played for large sums it is vital that the cards be properly randomized, but for many games this is less critical, and in fact player experience can suffer when the cards are shuffled too well.", "The official skat rules stipulate that the cards are ''shuffled well'', but according to a decision of the German skat court, a one-handed player should ask another player to do the shuffling, rather than use a shuffling machine, as it would shuffle the cards ''too'' well.", "French belote rules go so far as to prescribe that the deck never be shuffled between hands.===Dealing===The dealer takes all of the cards in the pack, arranges them so that they are in a uniform stack, and shuffles them.", "In strict play, the dealer then offers the deck to the previous player (in the sense of the game direction) for ''cutting''.", "If the deal is clockwise, this is the player to the dealer's right; if counterclockwise, it is the player to the dealer's left.", "The invitation to cut is made by placing the pack, face downward, on the table near the player who is to cut: who then lifts the upper portion of the pack clear of the lower portion and places it alongside.", "(Normally the two portions have about equal size.", "Strict rules often indicate that each portion must contain a certain minimum number of cards, such as three or five.)", "The formerly lower portion is then replaced on top of the formerly upper portion.", "Instead of cutting, one may also knock on the deck to indicate that one trusts the dealer to have shuffled fairly.The actual ''deal'' (distribution of cards) is done in the direction of play, beginning with eldest hand.", "The dealer holds the pack, face down, in one hand, and removes cards from the top of it with his or her other hand to distribute to the players, placing them face down on the table in front of the players to whom they are dealt.", "The cards may be dealt one at a time, or in batches of more than one card; and either the entire pack or a determined number of cards are dealt out.", "The undealt cards, if any, are left face down in the middle of the table, forming the ''stock'' (also called the talon, widow, skat or kitty depending on the game and region).Throughout the shuffle, cut, and deal, the dealer should prevent the players from seeing the faces of any of the cards.", "The players should not try to see any of the faces.", "Should a player accidentally see a card, other than one's own, proper etiquette would be to admit this.", "It is also dishonest to try to see cards as they are dealt, or to take advantage of having seen a card.", "Should a card accidentally become exposed, (visible to all), any player can demand a redeal (all the cards are gathered up, and the shuffle, cut, and deal are repeated) or that the card be replaced randomly into the deck (\"burning\" it) and a replacement dealt from the top to the player who was to receive the revealed card.When the deal is complete, all players pick up their cards, or \"hand\", and hold them in such a way that the faces can be seen by the holder of the cards but not the other players, or vice versa depending on the game.", "It is helpful to fan one's cards out so that if they have corner indices all their values can be seen at once.", "In most games, it is also useful to sort one's hand, rearranging the cards in a way appropriate to the game.", "For example, in a trick-taking game it may be easier to have all one's cards of the same suit together, whereas in a rummy game one might sort them by rank or by potential combinations." ], [ "Signalling", "Normally communication between partners about tactics or the cards in their hands is forbidden.", "However, in a small number of games communication and/or signalling is permitted and very much part of the play.", "Most of these games are very old and, often, have rules of play that allow any card to be played at any time.", "Such games include:* Karnöffel, the oldest card game in Europe still played in some form today, played with German-suited cards, and its surviving descendants:** Knüffeln (north Germany) and Styrivolt (Faroes) played with 48 French-suited cards** Kaiserspiel, Swiss game with a Swiss-suited pack of 48 cards* ''Mus'', a Basque game known since the 18th century, played with a Spanish deck of forty cards;* Brisca, a Spanish game adapted from the French Brisque, is played with a Spanish pack of forty cards;* ''Watten'', a Bavarian and Austrian game, is played with 36 German-suited cards;* Perlaggen, a Tyrolean game played with 33 German-suited cards;* Truc y Flou, a card game of Aragonese origin.", "* Trut or Truc, reported in the west of France from the 16th century, also known in Catalonia and South America (as ''Truco'')." ], [ "Rules", "A new card game starts in a small way, either as someone's invention, or as a modification of an existing game.", "Those playing it may agree to change the rules as they wish.", "The rules that they agree on become the \"house rules\" under which they play the game.", "A set of house rules may be accepted as valid by a group of players wherever they play, as it may also be accepted as governing all play within a particular house, café, or club.When a game becomes sufficiently popular, so that people often play it with strangers, there is a need for a generally accepted set of rules.", "This need is often met when a particular set of house rules becomes generally recognized.", "For example, when Whist became popular in 18th-century England, players in the Portland Club agreed on a set of house rules for use on its premises.", "Players in some other clubs then agreed to follow the \"Portland Club\" rules, rather than go to the trouble of codifying and printing their own sets of rules.", "The Portland Club rules eventually became generally accepted throughout England and Western cultures.There is nothing static or \"official\" about this process.", "For the majority of games, there is no one set of universal rules by which the game is played, and the most common ruleset is no more or less than that.", "Many widely played card games, such as Canasta and Pinochle, have no official regulating body.", "The most common ruleset is often determined by the most popular distribution of rulebooks for card games.", "Perhaps the original compilation of popular playing card games was collected by Edmund Hoyle, a self-made authority on many popular parlor games.", "The U.S.", "Playing Card Company now owns the eponymous Hoyle brand, and publishes a series of rulebooks for various families of card games that have largely standardized the games' rules in countries and languages where the rulebooks are widely distributed.", "However, players are free to, and often do, invent \"house rules\" to supplement or even largely replace the \"standard\" rules.If there is a sense in which a card game can have an official set of rules, it is when that card game has an \"official\" governing body.", "For example, the rules of tournament bridge are governed by the World Bridge Federation, and by local bodies in various countries such as the American Contract Bridge League in the U.S., and the English Bridge Union in England.", "The rules of skat are governed by The International Skat Players Association and, in Germany, by the ''Deutscher Skatverband'' which publishes the ''Skatordnung''.", "The rules of French tarot are governed by the Fédération Française de Tarot.", "The rules of Schafkopf are laid down by the ''Schafkopfschule'' in Munich.", "Even in these cases, the rules must only be followed at games sanctioned by these governing bodies or where the tournament organisers specify them.", "Players in informal settings are free to implement agreed supplemental or substitute rules.", "For example, in Schafkopf there are numerous local variants sometimes known as \"impure\" Schafkopf and specified by assuming the official rules and describing the additions e.g.", "\"with Geier and Bettel, tariff 5/10 cents\".===Rule infractions===An infraction is any action which is against the rules of the game, such as playing a card when it is not one's turn to play or the accidental exposure of a card, informally known as \"bleeding.", "\"In many official sets of rules for card games, the rules specifying the penalties for various infractions occupy more pages than the rules specifying how to play correctly.", "This is tedious but necessary for games that are played seriously.", "Players who intend to play a card game at a high level generally ensure before beginning that all agree on the penalties to be used.", "When playing privately, this will normally be a question of agreeing house rules.", "In a tournament, there will probably be a tournament director who will enforce the rules when required and arbitrate in cases of doubt.If a player breaks the rules of a game deliberately, this is cheating.", "The rest of this section is therefore about accidental infractions, caused by ignorance, clumsiness, inattention, etc.As the same game is played repeatedly among a group of players, precedents build up about how a particular infraction of the rules should be handled.", "For example, \"Sheila just led a card when it wasn't her turn.", "Last week when Jo did that, we agreed ...", "etc.\"", "Sets of such precedents tend to become established among groups of players, and to be regarded as part of the house rules.", "Sets of house rules may become formalized, as described in the previous section.", "Therefore, for some games, there is a \"proper\" way of handling infractions of the rules.", "But for many games, without governing bodies, there is no standard way of handling infractions.In many circumstances, there is no need for special rules dealing with what happens after an infraction.", "As a general principle, the person who broke a rule should not benefit from it, and the other players should not lose by it.", "An exception to this may be made in games with fixed partnerships, in which it may be felt that the partner(s) of the person who broke a rule should also not benefit.", "The penalty for an accidental infraction should be as mild as reasonable, consistent with there being a possible benefit to the person responsible." ], [ "Playing cards", "A Chinese playing card dated c. 1400 AD, Ming dynastyThe oldest surviving reference to the card game in world history is from the 9th century China, when the '' Collection of Miscellanea at Duyang'', written by Tang-dynasty writer Su E, described Princess Tongchang (daughter of Emperor Yizong of Tang) playing the \"leaf game\" with members of the Wei clan (the family of the princess's husband) in 868 .", "The Song dynasty statesman and historian Ouyang Xiu has noted that paper playing cards arose in connection to an earlier development in the book format from scrolls to pages.Mamluk playing card (king of cups), c.15th centuryPlaying cards first appeared in Europe in the last quarter of the 14th century.", "The earliest European references speak of a Saracen or Moorish game called ''naib'', and in fact an almost complete Mamluk Egyptian deck of 52 cards in a distinct oriental design has survived from around the same time, with the four suits ''swords'', ''polo sticks'', ''cups'' and ''coins'' and the ranks ''king'', ''governor'', ''second governor'', and ''ten'' to ''one''.The 1430s in Italy saw the invention of the tarot deck, a full Latin-suited deck augmented by suitless cards with painted motifs that played a special role as trumps.", "Tarot card games are still played with (subsets of) these decks in parts of Central Europe.", "A full tarot deck contains 14 cards in each suit; low cards labeled 1–10, and court cards (jack), (cavalier/knight), (queen), and (king), plus the fool or excuse card, and 21 trump cards.", "In the 18th century the card images of the traditional Italian tarot decks became popular in cartomancy and evolved into \"esoteric\" decks used primarily for the purpose; today most tarot decks sold in North America are the occult type, and are closely associated with fortune telling.", "In Europe, \"playing tarot\" decks remain popular for games, and have evolved since the 18th century to use regional suits (spades, hearts, diamonds and clubs in France; leaves, hearts, bells and acorns in Germany) as well as other familiar aspects of the English-pattern pack such as corner card indices and \"stamped\" card symbols for non-court cards.", "Decks differ regionally based on the number of cards needed to play the games; the French tarot consists of the \"full\" 78 cards, while Germanic, Spanish and Italian Tarot variants remove certain values (usually low suited cards) from the deck, creating a deck with as few as 32 cards.The French suits were introduced around 1480 and, in France, mostly replaced the earlier Latin suits of ''swords'', ''clubs'', ''cups'' and ''coins''.", "(which are still common in Spanish- and Portuguese-speaking countries as well as in some northern regions of Italy) The suit symbols, being very simple and single-color, could be stamped onto the playing cards to create a deck, thus only requiring special full-color card art for the court cards.", "This drastically simplifies the production of a deck of cards versus the traditional Italian deck, which used unique full-color art for each card in the deck.", "The French suits became popular in English playing cards in the 16th century (despite historic animosity between France and England), and from there were introduced to British colonies including North America.", "The rise of Western culture has led to the near-universal popularity and availability of French-suited playing cards even in areas with their own regional card art.In Japan, a distinct 48-card hanafuda deck is popular.", "It is derived from 16th-century Portuguese decks, after undergoing a long evolution driven by laws enacted by the Tokugawa shogunate attempting to ban the use of playing cardsThe best-known deck internationally is the English pattern of the 52-card French deck, also called the International or Anglo-American pattern, used for such games as poker and contract bridge.", "It contains one card for each unique combination of thirteen ''ranks'' and the four French ''suits'' ''spades'', ''hearts'', ''diamonds'', and ''clubs''.", "The ranks (from highest to lowest in bridge and poker) are ''ace'', ''king'', ''queen'', ''jack'' (or ''knave''), and the numbers from ''ten'' down to ''two'' (or ''deuce'').", "The trump cards and ''knight'' cards from the French playing tarot are not included.Originally the term ''knave'' was more common than \"jack\"; the card had been called a jack as part of the terminology of All-Fours since the 17th century, but the word was considered vulgar.", "(Note the exclamation by Estella in Charles Dickens's novel ''Great Expectations'': \"He calls the knaves, Jacks, this boy!\")", "However, because the card abbreviation for knave (\"Kn\") was so close to that of the king, it was very easy to confuse them, especially after suits and rankings were moved to the corners of the card in order to enable people to fan them in one hand and still see all the values.", "(The earliest known deck to place suits and rankings in the corner of the card is from 1693, but these cards did not become common until after 1864 when Hart reintroduced them along with the knave-to-jack change.)", "However, books of card games published in the third quarter of the 19th century evidently still referred to the \"knave\", and the term with this definition is still recognized in the United Kingdom.Chinese mother-of-pearl gambling tokens used in scoring and bidding of card games.In the 17th century, a French, five-trick, gambling game called Bête became popular and spread to Germany, where it was called La Bete and England where it was named Beast.", "It was a derivative of Triomphe and was the first card game in history to introduce the concept of bidding.Chinese handmade mother-of-pearl gaming counters were used in scoring and bidding of card games in the West during the approximate period of 1700–1840.The gaming counters would bear an engraving such as a coat of arms or a monogram to identify a family or individual.", "Many of the gaming counters also depict Chinese scenes, flowers or animals.", "Queen Charlotte is one prominent British individual who is known to have played with the Chinese gaming counters.", "Card games such as Ombre, Quadrille and Pope Joan were popular at the time and required counters for scoring.", "The production of counters declined after Whist, with its different scoring method, became the most popular card game in the West.Based on the association of card games and gambling, Pope Benedict XIV banned card games on October 17, 1750." ], [ "See also", "* Game of chance* Game of skill* R. F. Foster (games)* Henry Jones (writer) who wrote under the pseudonym \"Cavendish\"* John Scarne* Dice game* List of card games by number of cards" ], [ "References" ], [ "Bibliography", "* Depaulis, Thierry (1985).", "\"Le Jeu de Cartes: Quelques Regles du Passe\" in ''The Playing-Card''.", "Vol.", "XIII (3).", "February 1985.pp.", "74–80.", "* Depaulis, Thierry (1990).", "\"Pochspiel: an 'International' Card Game of the 15th Century – Part I\" in ''The Playing-Card'', Vol.", "19, No.", "2 (November 1990), pp.", "52–67.", "* Florio, John (1591).", "''Second Frutes''.", "London: Woodcock.", "* Parlett, David (2007).", "\"The origins of Euchre\" in ''The Playing-Card'', 35 (4), Apr–June 2007.pp.", "255–261.", "* Parlett, David (1991).", "''A History of Card Games'', OUP, Oxford.", "* * Skelton (1522).", "''Why not to Court''.", "Cited in the OED.", "See David Parlett's article: ''Laugh and Lie Down''." ], [ "External links", "* International Playing Card Society* Rules for historic card games* Collection of rules to many card games" ] ]

[ [ "Cross-stitch" ], [ "Introduction", "sampler, GermanyCross stitching using a hoop and showing use of enamel needle minder'''Cross-stitch''' is a form of sewing and a popular form of counted-thread embroidery in which X-shaped stitches in a tiled, raster-like pattern are used to form a picture.", "The stitcher counts the threads on a piece of evenweave fabric (such as linen) in each direction so that the stitches are of uniform size and appearance.", "This form of cross-stitch is also called '''counted cross-stitch''' in order to distinguish it from other forms of cross-stitch.", "Sometimes cross-stitch is done on designs printed on the fabric ('''stamped cross-stitch'''); the stitcher simply stitches over the printed pattern.", "Cross-stitch is often executed on easily countable fabric called aida cloth, whose weave creates a plainly visible grid of squares with holes for the needle at each corner.Fabrics used in cross-stitch include linen, aida cloth, and mixed-content fabrics called 'evenweave' such as jobelan.", "All cross-stitch fabrics are technically \"evenweave\" as the term refers to the fact that the fabric is woven to make sure that there are the same number of threads per inch in both the warp and the weft (i.e.", "vertically and horizontally).", "Fabrics are categorized by threads per inch (referred to as 'count'), which can range from 11 to 40 count.Counted cross-stitch projects are worked from a gridded pattern called a chart and can be used on any count fabric; the count of the fabric and the number of threads per stitch determine the size of the finished stitching.", "For example, if a given design is stitched on a 28 count cross-stitch fabric with each cross worked over two threads, the finished stitching size is the same as it would be on a 14 count aida cloth fabric with each cross worked over one square.", "These methods are referred to as \"2 over 2\" (2 embroidery threads used to stitch over 2 fabric threads) and \"1 over 1\" (1 embroidery thread used to stitch over 1 fabric thread or square), respectively.", "There are different methods of stitching a pattern, including the cross-country method where one colour is stitched at a time, or the parking method where one block of fabric is stitched at a time and the end of the thread is \"parked\" at the next point the same colour occurs in the pattern." ], [ "History", "Cross-stitch sampler by Sarah Littleton, 1868Cross-stitch can be found all over the world since the middle ages.", "Many folk museums show examples of clothing decorated with cross-stitch, especially from continental Europe and Asia.The cross-stitch sampler is called that because it was generally stitched by a young girl to learn how to stitch and to record alphabet and other patterns to be used in her household sewing.", "These samples of her stitching could be referred back to over the years.", "Often, motifs and initials were stitched on household items to identify their owner, or simply to decorate the otherwise-plain cloth.", "The earliest known cross stitch sampler made in the United States is currently housed at Pilgrim Hall in Plymouth, Massachusetts.", "The sampler was created by Loara Standish, daughter of Captain Myles Standish and pioneer of the Leviathan stitch, circa 1653.Detail of floral border pattern in cotton.", "Tea cloth (small tablecloth), Hungary, mid-twentieth century.Traditionally, cross-stitch was used to embellish items like household linens, tablecloths, dishcloths, and doilies (only a small portion of which would actually be embroidered, such as a border).", "Although there are many cross-stitchers who still employ it in this fashion, it is now increasingly popular to work the pattern on pieces of fabric and hang them on the wall for decoration.", "Cross-stitch is also often used to make greeting cards, pillow tops, or as inserts for box tops, coasters and trivets.Cross stitch from Surif.", "Top half of picture is the reverse side.Multicoloured, shaded, painting-like patterns as we know them today are a fairly modern development, deriving from similar shaded patterns of Berlin wool work of the mid-nineteenth century.", "Besides designs created expressly for cross-stitch, there are software programs that convert a photograph or a fine art image into a chart suitable for stitching.", "One example of this is in the cross-stitched reproduction of the Sistine Chapel charted and stitched by Joanna Lopianowski-Roberts.There are many cross-stitching \"guilds\" and groups across the United States and Europe which offer classes, collaborate on large projects, stitch for charity, and provide other ways for local cross-stitchers to get to know one another.", "Individually owned local needlework shops (LNS) often have stitching nights at their shops, or host weekend stitching retreats.Today, cotton floss is the most common embroidery thread.", "It is a thread made of mercerized cotton, composed of six strands that are only loosely twisted together and easily separable.", "While there are other manufacturers, the two most-commonly used (and oldest) brands are DMC and Anchor, both of which have been manufacturing embroidery floss since the 1800s.Other materials used are pearl (or perle) cotton, Danish flower thread, silk and Rayon.", "Different wool threads, metallic threads or other novelty threads are also used, sometimes for the whole work, but often for accents and embellishments.", "Hand-dyed cross-stitch floss is created just as the name implies—it is dyed by hand.", "Because of this, there are variations in the amount of color throughout the thread.", "Some variations can be subtle, while some can be a huge contrast.", "Some also have more than one color per thread.Cross-stitch is widely used in traditional Palestinian dressmaking.", "Palestinian cross stitch is called tatreez.", "In 2021, tatreez was added to the UNESCO List of the Intangible Cultural Heritage of Humanity." ], [ "Related stitches and forms of embroidery", "Ukrainian girls in traditional-style embroidered costumesA cross-stitching created with the use of different color fabricsThe cross-stitch can be executed partially such as in quarter-, half-, and three-quarter-stitches.", "A single straight stitch, done in the form of backstitching, is often used as an outline, to add detail or definition.There are many stitches which are related structurally to cross-stitch.", "The best known are Italian cross-stitch (as seen in Assisi embroidery), long-armed cross-stitch, and Montenegrin stitch.", "Italian cross-stitch and Montenegrin stitch are reversible, meaning the work looks the same on both sides.", "These styles have a slightly different look than ordinary cross-stitch.", "These more difficult stitches are rarely used in mainstream embroidery, but they are still used to recreate historical pieces of embroidery or by the creative and adventurous stitcher.", "The double cross-stitch, also known as a Leviathan stitch or Smyrna cross-stitch, combines a cross-stitch with an upright cross-stitch.Berlin wool work and similar petit point stitchery resembles the heavily shaded, opulent styles of cross-stitch, and sometimes also used charted patterns on paper.Cross-stitch is often combined with other popular forms of embroidery, such as Hardanger embroidery or blackwork embroidery.", "Cross-stitch may also be combined with other work, such as canvaswork or drawn thread work.", "Beadwork and other embellishments such as paillettes, charms, small buttons and specialty threads of various kinds may also be used.", "Cross stitch can often be used in needlepoint." ], [ "Recent trends for cross stitch", "Cross-stitching sampleCross-stitch has become increasingly popular with the younger generation of Europe in recent years.", "Retailers such as John Lewis experienced a 17% rise in sales of haberdashery products between 2009 and 2010.Hobbycraft, a chain of stores selling craft supplies, also enjoyed an 11% increase in sales over the year to February 22, 2009.Knitting and cross-stitching have become more popular hobbies for a younger market, in contrast to its traditional reputation as a hobby for retirees.", "Sewing and craft groups such as Stitch and Bitch London have resurrected the idea of the traditional craft club.", "At Clothes Show Live 2010 there was a new area called \"Sknitch\" promoting modern sewing, knitting and embroidery.In a departure from the traditional designs associated with cross-stitch, there is a current trend for more postmodern or tongue-in-cheek designs featuring retro images or contemporary sayings.", "It is linked to a concept known as 'subversive cross-stitch', which involves more risque designs, often fusing the traditional sampler style with sayings designed to shock or be incongruous with the old-fashioned image of cross-stitch.Stitching designs on other materials can be accomplished by using waste canvas.", "This is a temporary gridded canvas similar to regular canvas used for embroidery that is held together by a water-soluble glue, which is removed after completion of stitch design.", "Other crafters have taken to cross-stitching on all manner of gridded objects as well including old kitchen strainers or chain-link fences.While cross stitch is traditionally a women's craft, it is growing in popularity among men." ], [ "Cross-stitch and feminism", "In the 21st century, an emphasis on feminist design has emerged within cross-stitch communities.", "Some cross-stitchers have commented on the way that the practice of embroidery makes them feel connected to the women who practised it before them.", "There is a push for all embroidery, including cross-stitch, to be respected as a significant art form." ], [ "Cross-stitch and computers", "The development of computer technology has also affected such a seemingly conservative craft as cross-stitch.", "With the help of computer visualization algorithms, it is now possible to create embroidery designs using a photograph or any other picture.", "Visualisation uses a drawing on a graphical grid, representing colors and / or symbols, which gives the user an indication of the possible use of colors, the position of those colors, and the type of stitch used, such as full cross or quarter stitch." ], [ "Flosstube", "An increasingly popular activity for cross-stitchers is to watch and make YouTube videos detailing their hobby.", "Flosstubers, as they are known, typically cover WIPs (Works in Progress), FOs (Finished Objects), and Haul (new patterns, thread, and fabric, as well as cross-stitching accessories, such as needle minders).", "Other accessories include but are not limited to: Floss organizers, thread conditioner, pin cushions, aida cloth or plastic canvas, and embroidery needles." ], [ "See also", "* Mosaic* Pixel art* Embroidery" ], [ "Notes" ], [ "References", "* Caulfield, S. F. A., and B. C. Saward, ''The Dictionary of Needlework'', 1885.", "* Enthoven, Jacqueline: ''The Creative Stitches of Embroidery'', Van Norstrand Rheinhold, 1964, .", "* Gillow, John, and Bryan Sentance: ''World Textiles'', Bulfinch Press/Little, Brown, 1999, .", "* Reader's Digest, ''Complete Guide to Needlework''.", "The Reader's Digest Association, Inc. (March 1992) ." ], [ "External links", "* Articles related to the recent comeback in popularity of cross stitch.", "\"Is Cross Stitch Dead?\"" ] ]

[ [ "Casino game" ], [ "Introduction", "Slot machines are a popular type of casino gameGames available in most casinos are commonly called '''casino games'''.", "In a casino game, the players gamble cash or casino chips on various possible random outcomes or combinations of outcomes.", "Casino games are also available in online casinos, where permitted by law.", "Casino games can also be played outside of casinos for entertainment purposes, like in parties or in school competitions, on machines that simulate gambling." ], [ "Categories", "Overhead view of a casino floor with table games (bottom) and slot machinesThere are three general categories of casino games: gaming machines, table games, and random number games.", "Gaming machines, such as slot machines and pachinko, are usually played by one player at a time and do not require the involvement of casino employees.", "Tables games, such as blackjack or craps, involve one or more players who are competing against the house (the casino itself) rather than each other.", "Table games are usually conducted by casino employees known as croupiers or dealers.", "Random number games are based on the selection of random numbers, either from a computerized random number generator or from other gaming equipment.", "Random number games may be played at a table or through the purchase of paper tickets or cards, such as keno or bingo.Some casino games combine multiple of the above aspects; for example, roulette is a table game conducted by a dealer, that involves random numbers.", "Casinos may also offer other types of gaming, such as hosting poker games or tournaments where players compete against each other." ], [ "Common casino games", "Games commonly found at casinos include table games, gaming machines and random number games.===Table games===In the United States, 'table game' is the term used for games of chance such as blackjack, craps, roulette, and baccarat that are played against the casino and operated by one or more live croupiers, as opposed to those played on a mechanical device like a slot machine or against other players instead of the casino, such as standard poker.Table games are popularly played in casinos and involve some form of legal gambling, but they are also played privately under varying house rules.", "The term has significance in that some jurisdictions permit casinos to have only slots and no table games.", "In some states, this law has resulted in casinos employing electronic table games, such as roulette, blackjack, and craps.Table games found in casinos include:* Baccarat* Blackjack* Craps* Roulette* Poker (Texas hold'em, Five-card draw, Omaha hold'em)* Big Six wheel* Pool===Gaming machines===Gaming machines found in casinos include:* Pachinko* Slot machine* Video lottery terminal* Video poker===Random numbers games===Random numbers games found in casinos include:* Bingo* Keno" ], [ "House advantage", "Casino games typically provide a predictable long-term advantage to the casino, or \"house\", while offering the players the possibility of a short-term gain that in some cases can be large.", "Some casino games have a skill element, where the players' decisions have an impact on the results.", "Players possessing sufficient skills to eliminate the inherent long-term disadvantage (the ''house edge'' or vigorish) in a casino game are referred to as advantage players.The players' disadvantage is a result of the casino not paying winning wagers according to the game's \"true odds\", which are the payouts that would be expected considering the odds of a wager either winning or losing.", "For example, if a game is played by wagering on the number that would result from the roll of one die, the true odds would be 6 times the amount wagered since there is a 1 in 6 chance of any single number appearing, assuming that the player gets the original amount wagered back.", "However, the casino may only pay 4 times the amount wagered for a winning wager.The house edge, or vigorish, is defined as the casino profit expressed as a percentage of the player's original bet.", "(In games such as blackjack or Spanish 21, the final bet may be several times the original bet, if the player doubles and splits.", ")In American roulette, there are two \"zeroes\" (0, 00) and 36 non-zero numbers (18 red and 18 black).", "This leads to a higher house edge compared to European roulette.", "The chances of a player, who bets 1 unit on red, winning are 18/38 and his chances of losing 1 unit are 20/38.The player's expected value is EV = (18/38 × 1) + (20/38 × (−1)) = 18/38 − 20/38 = −2/38 = −5.26%.", "Therefore, the house edge is 5.26%.", "After 10 spins, betting 1 unit per spin, the average house profit will be 10 × 1 × 5.26% = 0.53 units.", "European roulette wheels have only one \"zero\" and therefore the house advantage (ignoring the en prison rule) is equal to 1/37 = 2.7%.The house edge of casino games varies greatly with the game, with some games having an edge as low as 0.3%.", "Keno can have house edges of up to 25%, slot machines having up to 15%.The calculation of the roulette house edge is a trivial exercise; for other games, this is not usually the case.", "Combinatorial analysis and/or computer simulation is necessary to complete the task.In games that have a skill element, such as blackjack or Spanish 21, the house edge is defined as the house advantage from optimal play (without the use of advanced techniques such as card counting), on the first hand of the shoe (the container that holds the cards).", "The set of optimal plays for all possible hands is known as \"basic strategy\" and is highly dependent on the specific rules and even the number of decks used.Traditionally, the majority of casinos have refused to reveal the house edge information for their slots games, and due to the unknown number of symbols and weightings of the reels, in most cases, it is much more difficult to calculate the house edge than in other casino games.", "However, due to some online properties revealing this information and some independent research conducted by Michael Shackleford in the offline sector, this pattern is slowly changing.In games where players are not competing against the house, such as poker, the casino usually earns money via a commission, known as a \"rake\".===Standard deviation===The luck factor in a casino game is quantified using standard deviations (SD).", "The standard deviation of a simple game like roulette can be calculated using the binomial distribution.", "In the binomial distribution, SD = , where ''n'' = number of rounds played, ''p'' = probability of winning, and ''q'' = probability of losing.", "The binomial distribution assumes a result of 1 unit for a win, and 0 units for a loss, rather than −1 units for a loss, which doubles the range of possible outcomes.", "Furthermore, if we flat bet at 10 units per round instead of 1 unit, the range of possible outcomes increases 10 fold.", ": SD (roulette, even-money bet) = 2''b'' , where ''b'' = flat bet per round, ''n'' = number of rounds, ''p'' = 18/38, and ''q'' = 20/38.For example, after 10 rounds at 1 unit per round, the standard deviation will be 2 × 1 × = 3.16 units.", "After 10 rounds, the expected loss will be 10 × 1 × 5.26% = 0.53.As you can see, standard deviation is many times the magnitude of the expected loss.The standard deviation for pai gow poker is the lowest out of all common casino games.", "Many casino games, particularly slot machines, have extremely high standard deviations.", "The bigger size of the potential payouts, the more the standard deviation may increase.As the number of rounds increases, eventually, the expected loss will exceed the standard deviation, many times over.", "From the formula, we can see that the standard deviation is proportional to the square root of the number of rounds played, while the expected loss is proportional to the number of rounds played.", "As the number of rounds increases, the expected loss increases at a much faster rate.", "This is why it is impossible for a gambler to win in the long term.", "It is the high ratio of short-term standard deviation to expected loss that fools gamblers into thinking that they can win.It is important for a casino to know both the house edge and variance for all of their games.", "The house edge tells them what kind of profit they will make as a percentage of turnover, and the variance tells them how much they need in the way of cash reserves.", "The mathematicians and computer programmers that do this kind of work are called gaming mathematicians and gaming analysts.", "Casinos do not have in-house expertise in this field, so they outsource their requirements to experts in the gaming analysis field." ], [ "See also", "* Gambler's fallacy" ], [ "References" ] ]

[ [ "Video game" ], [ "Introduction", "First-generation ''Pong'' console at the Computerspielemuseum Berlin|alt=Two children playing ''Pong'' on a television set.A '''video game''' or '''computer game''' is an electronic game that involves interaction with a user interface or input device (such as a joystick, controller, keyboard, or motion sensing device) to generate visual feedback from a display device, most commonly shown in a video format on a television set, computer monitor, flat-panel display or touchscreen on handheld devices, or a virtual reality headset.", "Most modern video games are audiovisual, with audio complement delivered through speakers or headphones, and sometimes also with other types of sensory feedback (e.g., haptic technology that provides tactile sensations).", "Some video games also allow microphone and webcam inputs for in-game chatting and livestreaming.Video games are typically categorized according to their hardware platform, which traditionally includes arcade video games, console games, and computer (PC) games; the latter also encompasses LAN games, online games, and browser games.", "More recently, the video game industry has expanded onto mobile gaming through mobile devices (such as smartphones and tablet computers), virtual and augmented reality systems, and remote cloud gaming.", "Video games are also classified into a wide range of genres based on their style of gameplay and target audience.The first video game prototypes in the 1950s and 1960s were simple extensions of electronic games using video-like output from large, room-sized mainframe computers.", "The first consumer video game was the arcade video game ''Computer Space'' in 1971.In 1972 came the iconic hit game ''Pong'' and the first home console, the Magnavox Odyssey.", "The industry grew quickly during the \"golden age\" of arcade video games from the late 1970s to early 1980s but suffered from the crash of the North American video game market in 1983 due to loss of publishing control and saturation of the market.", "Following the crash, the industry matured, was dominated by Japanese companies such as Nintendo, Sega, and Sony, and established practices and methods around the development and distribution of video games to prevent a similar crash in the future, many of which continue to be followed.", "In the 2000s, the core industry centered on \"AAA\" games, leaving little room for riskier experimental games.", "Coupled with the availability of the Internet and digital distribution, this gave room for independent video game development (or \"indie games\") to gain prominence into the 2010s.", "Since then, the commercial importance of the video game industry has been increasing.", "The emerging Asian markets and proliferation of smartphone games in particular are altering player demographics towards casual gaming and increasing monetization by incorporating games as a service.Today, video game development requires numerous interdisciplinary skills, vision, teamwork, and liaisons between different parties, including developers, publishers, distributors, retailers, hardware manufacturers, and other marketers, to successfully bring a game to its consumers.", ", the global video game market had estimated annual revenues of across hardware, software, and services, which is three times the size of the global music industry and four times that of the film industry in 2019, making it a formidable heavyweight across the modern entertainment industry.", "The video game market is also a major influence behind the electronics industry, where personal computer component, console, and peripheral sales, as well as consumer demands for better game performance, have been powerful driving factors for hardware design and innovation." ], [ "Origins", "''Tennis for Two'' (1958), an early analog computer game that used an oscilloscope for a displayEarly video games use interactive electronic devices with various display formats.", "The earliest example is from 1947—a \"cathode-ray tube amusement device\" was filed for a patent on 25 January 1947, by Thomas T. Goldsmith Jr. and Estle Ray Mann, and issued on 14 December 1948, as U.S. Patent 2455992.Inspired by radar display technology, it consists of an analog device allowing a user to control the parabolic arc of a dot on the screen to simulate a missile being fired at targets, which are paper drawings fixed to the screen.", "Other early examples include Christopher Strachey's draughts game, the Nimrod computer at the 1951 Festival of Britain; ''OXO'', a tic-tac-toe computer game by Alexander S. Douglas for the EDSAC in 1952; ''Tennis for Two'', an electronic interactive game engineered by William Higinbotham in 1958; and ''Spacewar!", "'', written by Massachusetts Institute of Technology students Martin Graetz, Steve Russell, and Wayne Wiitanen's on a DEC PDP-1 computer in 1961.Each game has different means of display: NIMROD has a panel of lights to play the game of Nim, OXO has a graphical display to play tic-tac-toe, ''Tennis for Two'' has an oscilloscope to display a side view of a tennis court, and ''Spacewar!''", "has the DEC PDP-1's vector display to have two spaceships battle each other.These preliminary inventions paved the way for the origins of video games today.", "Ralph H. Baer, while working at Sanders Associates in 1966, devised a control system to play a rudimentary game of table tennis on a television screen.", "With the company's approval, Baer built the prototype \"Brown Box\".", "Sanders patented Baer's inventions and licensed them to Magnavox, which commercialized it as the first home video game console, the Magnavox Odyssey, released in 1972.Separately, Nolan Bushnell and Ted Dabney, inspired by seeing ''Spacewar!''", "running at Stanford University, devised a similar version running in a smaller coin-operated arcade cabinet using a less expensive computer.", "This was released as ''Computer Space'', the first arcade video game, in 1971.Bushnell and Dabney went on to form Atari, Inc., and with Allan Alcorn, created their second arcade game in 1972, the hit ping pong-style ''Pong'', which was directly inspired by the table tennis game on the Odyssey.", "Sanders and Magnavox sued Atari for infringement of Baer's patents, but Atari settled out of court, paying for perpetual rights to the patents.", "Following their agreement, Atari made a home version of ''Pong'', which was released by Christmas 1975.The success of the Odyssey and ''Pong'', both as an arcade game and home machine, launched the video game industry.", "Both Baer and Bushnell have been titled \"Father of Video Games\" for their contributions." ], [ "Terminology", "The term \"video game\" was developed to distinguish this class of electronic games that were played on some type of video display rather than on a teletype printer, audio speaker or similar device.", "This also distinguished from many handheld electronic games like ''Merlin'' which commonly used LED lights for indicators but did not use these in combination for imaging purposes.", "\"Computer game\" may also be used as a descriptor, as all these types of games essentially require the use of a computer processor, and in some cases, it is used interchangeably with \"video game\".", "Particularly in the United Kingdom and Western Europe, this is common due to the historic relevance of domestically produced microcomputers.", "Other terms used include digital game, for example by the Australian Bureau of Statistics.", "However, the term \"computer game\" can also be used to more specifically refer to games played primarily on personal computers or other type of flexible hardware systems (also known as a PC game), as a way distinguish them from console games, arcade games or mobile games.", "Other terms such as \"television game\" or \"telegame\" had been used in the 1970s and early 1980s, particularly for the home gaming consoles that rely on connection to a television set.", "In Japan, where consoles like the Odyssey were first imported and then made within the country by the large television manufacturers such as Toshiba and Sharp Corporation, such games are known as \"TV games\", or ''TV geemu'' or ''terebi geemu''.", "\"Electronic game\" may also be used to refer to video games, but this also incorporates devices like early handheld electronic games that lack any video output.", "and the term \"TV game\" is still commonly used into the 21st century.The first appearance of the term \"video game\" emerged around 1973.The Oxford English Dictionary cited a 10 November 1973 ''BusinessWeek'' article as the first printed use of the term.", "Though Bushnell believed the term came from a vending magazine review of ''Computer Space'' in 1971, a review of the major vending magazines ''Vending Times'' and ''Cashbox'' showed that the term came much earlier, appearing first around March 1973 in these magazines in mass usage including by the arcade game manufacturers.", "As analyzed by video game historian Keith Smith, the sudden appearance suggested that the term had been proposed and readily adopted by those involved.", "This appeared to trace to Ed Adlum, who ran ''Cashbox''s coin-operated section until 1972 and then later founded ''RePlay Magazine'', covering the coin-op amusement field, in 1975.In a September 1982 issue of ''RePlay'', Adlum is credited with first naming these games as \"video games\": \"RePlay's Eddie Adlum worked at 'Cash Box' when 'TV games' first came out.", "The personalities in those days were Bushnell, his sales manager Pat Karns and a handful of other 'TV game' manufacturers like Henry Leyser and the McEwan brothers.", "It seemed awkward to call their products 'TV games', so borrowing a word from ''Billboard''s description of movie jukeboxes, Adlum started to refer to this new breed of amusement machine as 'video games.'", "The phrase stuck.\"", "Adlum explained in 1985 that up until the early 1970s, amusement arcades typically had non-video arcade games such as pinball machines and electro-mechanical games.", "With the arrival of video games in arcades during the early 1970s, there was initially some confusion in the arcade industry over what term should be used to describe the new games.", "He \"wrestled with descriptions of this type of game,\" alternating between \"TV game\" and \"television game\" but \"finally woke up one day\" and said, \"what the hell... video game!", "\"For many years, the traveling Videotopia exhibit served as the closest representation of such a vital resource.", "In addition to collecting home video game consoles, the Electronics Conservancy organization set out to locate and restore 400 antique arcade cabinets after realizing that the majority of these games had been destroyed and feared the loss of their historical significance.", "Video games have significantly began to be seen in the real-world as a purpose to present history in a way of understanding the methodology and terms that are being compared.", "Researchers have looked at how historical representations affect how the public perceives the past, and digital humanists encourage historians to use video games as primary materials.", "Video games, considering their past and age, have over time progressed as what a video game really means.", "Whether played through a monitor, TV, or a hand-held device, there are many ways that video games are being displayed for users to enjoy.", "People have drawn comparisons between flow-state-engaged video gamers and pupils in conventional school settings.", "In traditional, teacher-led classrooms, students have little say in what they learn, are passive consumers of the information selected by teachers, are required to follow the pace and skill level of the group (group teaching), and receive brief, imprecise, normative feedback on their work.", "Video games, as they continue to develop into better graphic definition and genre's, create new terminology when something unknown tends to become known.", "Yearly, consoles are being created to compete against other brands with similar functioning features that tends to lead the consumer into which they'd like to purchase.", "Now, companies have moved towards games only the specific console can play to grasp the consumer into purchasing their product compared to when video games first began, there was little to no variety.", "In 1989, a console war begun with Nintendo, one of the biggest in gaming was up against target, Sega with their brand new Master System which, failed to compete, allowing the Nintendo Emulator System to be one of the most consumed product in the world.", "More technology continued to be created, as the computer began to be used in people's houses for more than just office and daily use.", "Games began being implemented into computers and have progressively grown since then with coded robots to play against you.", "Early games like tic-tac-toe, solitaire, and Tennis for Two were great ways to bring new gaming to another system rather than one specifically meant for gaming.===Definition===While many games readily fall into a clear, well-understood definition of video games, new genres and innovations in game development have raised the question of what are the essential factors of a video game that separate the medium from other forms of entertainment.The introduction of interactive films in the 1980s with games like ''Dragon's Lair'', featured games with full motion video played off a form of media but only limited user interaction.", "This had required a means to distinguish these games from more traditional board games that happen to also use external media, such as the ''Clue VCR Mystery Game'' which required players to watch VCR clips between turns.", "To distinguish between these two, video games are considered to require some interactivity that affects the visual display.Most video games tend to feature some type of victory or winning conditions, such as a scoring mechanism or a final boss fight.", "The introduction of walking simulators (adventure games that allow for exploration but lack any objectives) like ''Gone Home'', and empathy games (video games that tend to focus on emotion) like ''That Dragon, Cancer'' brought the idea of games that did not have any such type of winning condition and raising the question of whether these were actually games.", "These are still commonly justified as video games as they provide a game world that the player can interact with by some means.The lack of any industry definition for a video game by 2021 was an issue during the case ''Epic Games v. Apple'' which dealt with video games offered on Apple's iOS App Store.", "Among concerns raised were games like ''Fortnite Creative'' and ''Roblox'' which created metaverses of interactive experiences, and whether the larger game and the individual experiences themselves were games or not in relation to fees that Apple charged for the App Store.", "Judge Yvonne Gonzalez Rogers, recognizing that there was yet an industry standard definition for a video game, established for her ruling that \"At a bare minimum, videogames appear to require some level of interactivity or involvement between the player and the medium\" compared to passive entertainment like film, music, and television, and \"videogames are also generally graphically rendered or animated, as opposed to being recorded live or via motion capture as in films or television\".", "Rogers still concluded that what is a video game \"appears highly eclectic and diverse\".===Video game terminology===''Freedoom'', a clone of the first-person shooter ''Doom''.", "Common elements include a heads-up display along the bottom that includes the player's remaining health and ammunition.", "The gameplay experience varies radically between video games, but many common elements exist.", "Most games will launch into a title screen and give the player a chance to review options such as the number of players before starting a game.", "Most games are divided into levels which the player must work the avatar through, scoring points, collecting power-ups to boost the avatar's innate attributes, all while either using special attacks to defeat enemies or moves to avoid them.", "This information is relayed to the player through a type of on-screen user interface such as a heads-up display atop the rendering of the game itself.", "Taking damage will deplete their avatar's health, and if that falls to zero or if the avatar otherwise falls into an impossible-to-escape location, the player will lose one of their lives.", "Should they lose all their lives without gaining an extra life or \"1-UP\", then the player will reach the \"game over\" screen.", "Many levels as well as the game's finale end with a type of boss character the player must defeat to continue on.", "In some games, intermediate points between levels will offer save points where the player can create a saved game on storage media to restart the game should they lose all their lives or need to stop the game and restart at a later time.", "These also may be in the form of a passage that can be written down and reentered at the title screen.Product flaws include software bugs which can manifest as glitches which may be exploited by the player; this is often the foundation of speedrunning a video game.", "These bugs, along with cheat codes, Easter eggs, and other hidden secrets that were intentionally added to the game can also be exploited.", "On some consoles, cheat cartridges allow players to execute these cheat codes, and user-developed trainers allow similar bypassing for computer software games.", "Both of which might make the game easier, give the player additional power-ups, or change the appearance of the game." ], [ "Components", "Arcade video game machines at the Sugoi arcade game hall in Malmi, Helsinki, FinlandTo distinguish from electronic games, a video game is generally considered to require a platform, the hardware which contains computing elements, to process player interaction from some type of input device and displays the results to a video output display.===Platform===Computer Games Museum in BerlinVideo games require a platform, a specific combination of electronic components or computer hardware and associated software, to operate.", "The term system is also commonly used.", "Games are typically designed to be played on one or a limited number of platforms, and exclusivity to a platform is used as a competitive edge in the video game market.", "However, games may be developed for alternative platforms than intended, which are described as ports or conversions.", "These also may be remasters - where most of the original game's source code is reused and art assets, models, and game levels are updated for modern systems – and remakes, where in addition to asset improvements, significant reworking of the original game and possibly from scratch is performed.The list below is not exhaustive and excludes other electronic devices capable of playing video games such as PDAs and graphing calculators.", ";PC games:PC games involve a player interacting with a personal computer (PC) connected to a video monitor.", "Personal computers are not dedicated game platforms, so there may be differences running the same game on different hardware.", "Also, the openness allows some features to developers like reduced software cost, increased flexibility, increased innovation, emulation, creation of modifications or mods, open hosting for online gaming (in which a person plays a video game with people who are in a different household) and others.", "A gaming computer is a PC or laptop intended specifically for gaming, typically using high-performance, high-cost components.", "In additional to personal computer gaming, there also exist games that work on mainframe computers and other similarly shared systems, with users logging in remotely to use the computer.", ";Home console:The PlayStation 2 is the best-selling video game console, with over 155 million units sold.A console game is played on a home console, a specialized electronic device that connects to a common television set or composite video monitor.", "Home consoles are specifically designed to play games using a dedicated hardware environment, giving developers a concrete hardware target for development and assurances of what features will be available, simplifying development compared to PC game development.", "Usually consoles only run games developed for it, or games from other platform made by the same company, but never games developed by its direct competitor, even if the same game is available on different platforms.", "It often comes with a specific game controller.", "Major console platforms include Xbox, PlayStation and Nintendo.", ";Handheld console:A handheld game console is a small, self-contained electronic device that is portable and can be held in a user's hands.", "It features the console, a small screen, speakers and buttons, joystick or other game controllers in a single unit.", "Like consoles, handhelds are dedicated platforms, and share almost the same characteristics.", "Handheld hardware usually is less powerful than PC or console hardware.", "Some handheld games from the late 1970s and early 1980s could only play one game.", "In the 1990s and 2000s, a number of handheld games used cartridges, which enabled them to be used to play many different games.", "The handheld console has waned in the 2010s as mobile device gaming has become a more dominant factor.", ";Arcade video game:A police-themed arcade game in which players use a light gun An arcade video game generally refers to a game played on an even more specialized type of electronic device that is typically designed to play only one game and is encased in a special, large coin-operated cabinet which has one built-in console, controllers (joystick, buttons, etc.", "), a CRT screen, and audio amplifier and speakers.", "Arcade games often have brightly painted logos and images relating to the theme of the game.", "While most arcade games are housed in a vertical cabinet, which the user typically stands in front of to play, some arcade games use a tabletop approach, in which the display screen is housed in a table-style cabinet with a see-through table top.", "With table-top games, the users typically sit to play.", "In the 1990s and 2000s, some arcade games offered players a choice of multiple games.", "In the 1980s, video arcades were businesses in which game players could use a number of arcade video games.", "In the 2010s, there are far fewer video arcades, but some movie theaters and family entertainment centers still have them.", ";Browser game:A browser game takes advantages of standardizations of technologies for the functionality of web browsers across multiple devices providing a cross-platform environment.", "These games may be identified based on the website that they appear, such as with Miniclip games.", "Others are named based on the programming platform used to develop them, such as Java and Flash games.", ";Mobile game:With the introduction of smartphones and tablet computers standardized on the iOS and Android operating systems, mobile gaming has become a significant platform.", "These games may use unique features of mobile devices that are not necessary present on other platforms, such as accelerometers, global positing information and camera devices to support augmented reality gameplay.", ";Cloud gaming:Cloud gaming requires a minimal hardware device, such as a basic computer, console, laptop, mobile phone or even a dedicated hardware device connected to a display with good Internet connectivity that connects to hardware systems by the cloud gaming provider.", "The game is computed and rendered on the remote hardware, using a number of predictive methods to reduce the network latency between player input and output on their display device.", "For example, the Xbox Cloud Gaming and PlayStation Now platforms use dedicated custom server blade hardware in cloud computing centers.", ";Virtual reality:Players using the PlayStation VR headsets in 2017 Virtual reality (VR) games generally require players to use a special head-mounted unit that provides stereoscopic screens and motion tracking to immerse a player within virtual environment that responds to their head movements.", "Some VR systems include control units for the player's hands as to provide a direct way to interact with the virtual world.", "VR systems generally require a separate computer, console, or other processing device that couples with the head-mounted unit.", ";Emulation:An emulator enables games from a console or otherwise different system to be run in a type of virtual machine on a modern system, simulating the hardware of the original and allows old games to be played.", "While emulators themselves have been found to be legal in United States case law, the act of obtaining the game software that one does not already own may violate copyrights.", "However, there are some official releases of emulated software from game manufacturers, such as Nintendo with its Virtual Console or Nintendo Switch Online offerings.", ";Backward compatibility:Backward compatibility is similar in nature to emulation in that older games can be played on newer platforms, but typically directly though hardware and build-in software within the platform.", "For example, the PlayStation 2 is capable of playing original PlayStation games simply by inserting the original game media into the newer console, while Nintendo's Wii could play GameCube titles as well in the same manner.===Game media===An unlabeled game cartridge for the Nintendo Entertainment SystemEarly arcade games, home consoles, and handheld games were dedicated hardware units with the game's logic built into the electronic componentry of the hardware.", "Since then, most video game platforms are considered programmable, having means to read and play multiple games distributed on different types of media or formats.", "Physical formats include ROM cartridges, magnetic storage including magnetic-tape data storage and floppy discs, optical media formats including CD-ROM and DVDs, and flash memory cards.", "Furthermore digital distribution over the Internet or other communication methods as well as cloud gaming alleviate the need for any physical media.", "In some cases, the media serves as the direct read-only memory for the game, or it may be the form of installation media that is used to write the main assets to the player's platform's local storage for faster loading periods and later updates.Games can be extended with new content and software patches through either expansion packs which are typically available as physical media, or as downloadable content nominally available via digital distribution.", "These can be offered freely or can be used to monetize a game following its initial release.", "Several games offer players the ability to create user-generated content to share with others to play.", "Other games, mostly those on personal computers, can be extended with user-created modifications or mods that alter or add onto the game; these often are unofficial and were developed by players from reverse engineering of the game, but other games provide official support for modding the game.===Input device===A North American Super NES game controller from the early 1990sVideo game can use several types of input devices to translate human actions to a game.", "Most common are the use of game controllers like gamepads and joysticks for most consoles, and as accessories for personal computer systems along keyboard and mouse controls.", "Common controls on the most recent controllers include face buttons, shoulder triggers, analog sticks, and directional pads (\"d-pads\").", "Consoles typically include standard controllers which are shipped or bundled with the console itself, while peripheral controllers are available as a separate purchase from the console manufacturer or third-party vendors.", "Similar control sets are built into handheld consoles and onto arcade cabinets.", "Newer technology improvements have incorporated additional technology into the controller or the game platform, such as touchscreens and motion detection sensors that give more options for how the player interacts with the game.", "Specialized controllers may be used for certain genres of games, including racing wheels, light guns and dance pads.", "Digital cameras and motion detection can capture movements of the player as input into the game, which can, in some cases, effectively eliminate the control, and on other systems such as virtual reality, are used to enhance immersion into the game.===Display and output===Handheld units, like the Game Boy, include built-in output screens and sound speakers.By definition, all video games are intended to output graphics to an external video display, such as cathode-ray tube televisions, newer liquid-crystal display (LCD) televisions and built-in screens, projectors or computer monitors, depending on the type of platform the game is played on.", "Features such as color depth, refresh rate, frame rate, and screen resolution are a combination of the limitations of the game platform and display device and the program efficiency of the game itself.", "The game's output can range from fixed displays using LED or LCD elements, text-based games, two-dimensional and three-dimensional graphics, and augmented reality displays.The game's graphics are often accompanied by sound produced by internal speakers on the game platform or external speakers attached to the platform, as directed by the game's programming.", "This often will include sound effects tied to the player's actions to provide audio feedback, as well as background music for the game.Some platforms support additional feedback mechanics to the player that a game can take advantage of.", "This is most commonly haptic technology built into the game controller, such as causing the controller to shake in the player's hands to simulate a shaking earthquake occurring in game." ], [ "Classifications", "Video games are frequently classified by a number of factors related to how one plays them.===Genre===''Dustforce'' is representative of the platform game genre as its gameplay involves jumping between platforms.A video game, like most other forms of media, may be categorized into genres.", "However, unlike film or television which use visual or narrative elements, video games are generally categorized into genres based on their gameplay interaction, since this is the primary means which one interacts with a video game.", "The narrative setting does not impact gameplay; a shooter game is still a shooter game, regardless of whether it takes place in a fantasy world or in outer space.", "An exception is the horror game genre, used for games that are based on narrative elements of horror fiction, the supernatural, and psychological horror.Genre names are normally self-describing in terms of the type of gameplay, such as action game, role playing game, or shoot 'em up, though some genres have derivations from influential works that have defined that genre, such as roguelikes from ''Rogue'', Grand Theft Auto clones from ''Grand Theft Auto III'', and battle royale games from the film ''Battle Royale''.", "The names may shift over time as players, developers and the media come up with new terms; for example, first-person shooters were originally called \"Doom clones\" based on the 1993 game.", "A hierarchy of game genres exist, with top-level genres like \"shooter game\" and \"action game\" that broadly capture the game's main gameplay style, and several subgenres of specific implementation, such as within the shooter game first-person shooter and third-person shooter.", "Some cross-genre types also exist that fall until multiple top-level genres such as action-adventure game.===Mode===A LAN party at the 2004 DreamHack with hundreds of playersA video game's mode describes how many players can use the game at the same type.", "This is primarily distinguished by single-player video games and multiplayer video games.", "Within the latter category, multiplayer games can be played in a variety of ways, including locally at the same device, on separate devices connected through a local network such as LAN parties, or online via separate Internet connections.", "Most multiplayer games are based on competitive gameplay, but many offer cooperative and team-based options as well as asymmetric gameplay.", "Online games use server structures that can also enable massively multiplayer online games (MMOs) to support hundreds of players at the same time.A small number of video games are zero-player games, in which the player has very limited interaction with the game itself.", "These are most commonly simulation games where the player may establish a starting state and then let the game proceed on its own, watching the results as a passive observer, such as with many computerized simulations of Conway's Game of Life.===Types===Most video games are intended for entertainment purposes.", "Different game types include:; Core games: Core or hard-core games refer to the typical perception of video games, developed for entertainment purposes.", "These games typically require a fair amount of time to learn and master, in contrast to casual games, and thus are most appealing to gamers rather than a broader audience.", "Most of the AAA video game industry is based around the delivery of core games.", "; Casual games: In contrast to core games, casual games are designed for ease of accessibility, simple to understand gameplay and quick to grasp rule sets, and aimed at mass market audience.", "They frequently support the ability to jump in and out of play on demand, such as during commuting or lunch breaks.", "Numerous browser and mobile games fall into the casual game area, and casual games often are from genres with low intensity game elements such as match three, hidden object, time management, and puzzle games.", "Causal games frequently use social-network game mechanics, where players can enlist the help of friends on their social media networks for extra turns or moves each day.", "Popular casual games include ''Tetris'' and ''Candy Crush Saga''.", "More recent, starting in the late 2010s, are hyper-casual games which use even more simplistic rules for short but infinitely replayable games, such as ''Flappy Bird''.", "; Educational games: Education software has been used in homes and classrooms to help teach children and students, and video games have been similarly adapted for these reasons, all designed to provide a form of interactivity and entertainment tied to game design elements.", "There are a variety of differences in their designs and how they educate the user.", "These are broadly split between edutainment games that tend to focus on the entertainment value and rote learning but are unlikely to engage in critical thinking, and educational video games that are geared towards problem solving through motivation and positive reinforcement while downplaying the entertainment value.", "Examples of educational games include ''The Oregon Trail'' and the ''Carmen Sandiego'' series.", "Further, games not initially developed for educational purposes have found their way into the classroom after release, such as that feature open worlds or virtual sandboxes like ''Minecraft'', or offer critical thinking skills through puzzle video games like ''SpaceChem''.", ";Serious games:''Microsoft Flight Simulator'' is an example of a simulation game.", "Further extending from educational games, serious games are those where the entertainment factor may be augmented, overshadowed, or even eliminated by other purposes for the game.", "Game design is used to reinforce the non-entertainment purpose of the game, such as using video game technology for the game's interactive world, or gamification for reinforcement training.", "Educational games are a form of serious games, but other types of games include fitness games that incorporate significant physical exercise to help keep the player fit (such as ''Wii Fit''), simulator games that resemble fight simulators to pilot aircraft (such as ''Microsoft Flight Simulator''), advergames that are built around the advertising of a product (such as ''Pepsiman''), and newsgames aimed at conveying a specific advocacy message (such as ''NarcoGuerra'').", ";Art games:Although video games have been considered an art form on their own, games may be developed to try to purposely communicate a story or message, using the medium as a work of art.", "These art or arthouse games are designed to generate emotion and empathy from the player by challenging societal norms and offering critique through the interactivity of the video game medium.", "They may not have any type of win condition and are designed to let the player explore through the game world and scenarios.", "Most art games are indie games in nature, designed based on personal experiences or stories through a single developer or small team.", "Examples of art games include ''Passage'', ''Flower'', and ''That Dragon, Cancer''.===Content rating===A typical ESRB rating label, listing the rating and specific content descriptors for ''Rabbids Go Home''Video games can be subject to national and international content rating requirements.", "Like with film content ratings, video game ratings typing identify the target age group that the national or regional ratings board believes is appropriate for the player, ranging from all-ages, to a teenager-or-older, to mature, to the infrequent adult-only games.", "Most content review is based on the level of violence, both in the type of violence and how graphic it may be represented, and sexual content, but other themes such as drug and alcohol use and gambling that can influence children may also be identified.", "A primary identifier based on a minimum age is used by nearly all systems, along with additional descriptors to identify specific content that players and parents should be aware of.The regulations vary from country to country but generally are voluntary systems upheld by vendor practices, with penalty and fines issued by the ratings body on the video game publisher for misuse of the ratings.", "Among the major content rating systems include:* Entertainment Software Rating Board (ESRB) that oversees games released in the United States.", "ESRB ratings are voluntary and rated along a E (Everyone), E10+ (Everyone 10 and older), T (Teen), M (Mature), and AO (Adults Only).", "Attempts to mandate video games ratings in the U.S. subsequently led to the landmark Supreme Court case, ''Brown v. Entertainment Merchants Association'' in 2011 which ruled video games were a protected form of art, a key victory for the video game industry.", "* Pan European Game Information (PEGI) covering the United Kingdom, most of the European Union and other European countries, replacing previous national-based systems.", "The PEGI system uses content rated based on minimum recommended ages, which include 3+, 8+, 12+, 16+, and 18+.", "* Australian Classification Board (ACB) oversees the ratings of games and other works in Australia, using ratings of G (General), PG (Parental Guidance), M (Mature), MA15+ (Mature Accompanied), R18+ (Restricted), and X (Restricted for pornographic material).", "ACB can also deny to give a rating to game (RC – Refused Classification).", "The ACB's ratings are enforceable by law, and importantly, games cannot be imported or purchased digitally in Australia if they have failed to gain a rating or were given the RC rating, leading to a number of notable banned games.", "* Computer Entertainment Rating Organization (CERO) rates games for Japan.", "Their ratings include A (all ages), B (12 and older), C (15 and over), D (17 and over), and Z (18 and over).Additionally, the major content system provides have worked to create the International Age Rating Coalition (IARC), a means to streamline and align the content ratings system between different region, so that a publisher would only need to complete the content ratings review for one provider, and use the IARC transition to affirm the content rating for all other regions.Certain nations have even more restrictive rules related to political or ideological content.", "Within Germany, until 2018, the Unterhaltungssoftware Selbstkontrolle (''Entertainment Software Self-Regulation'') would refuse to classify, and thus allow sale, of any game depicting Nazi imagery, and thus often requiring developers to replace such imagery with fictional ones.", "This ruling was relaxed in 2018 to allow for such imagery for \"social adequacy\" purposes that applied to other works of art.", "China's video game segment is mostly isolated from the rest of the world due to the government's censorship, and all games published there must adhere to strict government review, disallowing content such as smearing the image of the Chinese Communist Party.", "Foreign games published in China often require modification by developers and publishers to meet these requirements." ], [ "Development", "Developers use various tools to create video games.", "Here an editor is fine-tuning the virtual camera system.Video game development and authorship, much like any other form of entertainment, is frequently a cross-disciplinary field.", "Video game developers, as employees within this industry are commonly referred, primarily include programmers and graphic designers.", "Over the years this has expanded to include almost every type of skill that one might see prevalent in the creation of any movie or television program, including sound designers, musicians, and other technicians; as well as skills that are specific to video games, such as the game designer.", "All of these are managed by producers.In the early days of the industry, it was more common for a single person to manage all of the roles needed to create a video game.", "As platforms have become more complex and powerful in the type of material they can present, larger teams have been needed to generate all of the art, programming, cinematography, and more.", "This is not to say that the age of the \"one-man shop\" is gone, as this is still sometimes found in the casual gaming and handheld markets, where smaller games are prevalent due to technical limitations such as limited RAM or lack of dedicated 3D graphics rendering capabilities on the target platform (e.g., some PDAs).Video games are programmed like any other piece of computer software.", "Prior to the mid-1970s, arcade and home consoles were programmed by assembling discrete electro-mechanical components on circuit boards, which limited games to relatively simple logic.", "By 1975, low-cost microprocessors were available at volume to be used for video game hardware, which allowed game developers to program more detailed games, widening the scope of what was possible.", "Ongoing improvements in computer hardware technology has expanded what has become possible to create in video games, coupled with convergence of common hardware between console, computer, and arcade platforms to simplify the development process.", "Today, game developers have a number of commercial and open source tools available for use to make games, often which are across multiple platforms to support portability, or may still opt to create their own for more specialized features and direct control of the game.", "Today, many games are built around a game engine that handles the bulk of the game's logic, gameplay, and rendering.", "These engines can be augmented with specialized engines for specific features, such as a physics engine that simulates the physics of objects in real-time.", "A variety of middleware exists to help developers to access other features, such as for playback of videos within games, network-oriented code for games that communicate via online services, matchmaking for online games, and similar features.", "These features can be used from a developers' programming language of choice, or they may opt to also use game development kits that minimize the amount of direct programming they have to do but can also limit the amount of customization they can add into a game.", "Like all software, video games usually undergo quality testing before release to assure there are no bugs or glitches in the product, though frequently developers will release patches and updates.With the growth of the size of development teams in the industry, the problem of cost has increased.", "Development studios need the best talent, while publishers reduce costs to maintain profitability on their investment.", "Typically, a video game console development team ranges from 5 to 50 people, and some exceed 100.In May 2009, ''Assassin's Creed II'' was reported to have a development staff of 450.The growth of team size combined with greater pressure to get completed projects into the market to begin recouping production costs has led to a greater occurrence of missed deadlines, rushed games and the release of unfinished products.While amateur and hobbyist game programming had existed since the late 1970s with the introduction of home computers, a newer trend since the mid-2000s is indie game development.", "Indie games are made by small teams outside any direct publisher control, their games being smaller in scope than those from the larger \"AAA\" game studios, and are often experiment in gameplay and art style.", "Indie game development are aided by larger availability of digital distribution, including the newer mobile gaming marker, and readily-available and low-cost development tools for these platforms.===Game theory and studies===Although departments of computer science have been studying the technical aspects of video games for years, theories that examine games as an artistic medium are a relatively recent development in the humanities.", "The two most visible schools in this emerging field are ludology and narratology.", "Narrativists approach video games in the context of what Janet Murray calls \"Cyberdrama\".", "That is to say, their major concern is with video games as a storytelling medium, one that arises out of interactive fiction.", "Murray puts video games in the context of the Holodeck, a fictional piece of technology from ''Star Trek'', arguing for the video game as a medium in which the player is allowed to become another person, and to act out in another world.", "This image of video games received early widespread popular support, and forms the basis of films such as ''Tron'', ''eXistenZ'' and ''The Last Starfighter''.Ludologists break sharply and radically from this idea.", "They argue that a video game is first and foremost a game, which must be understood in terms of its rules, interface, and the concept of play that it deploys.", "Espen J. Aarseth argues that, although games certainly have plots, characters, and aspects of traditional narratives, these aspects are incidental to gameplay.", "For example, Aarseth is critical of the widespread attention that narrativists have given to the heroine of the game ''Tomb Raider'', saying that \"the dimensions of Lara Croft's body, already analyzed to death by film theorists, are irrelevant to me as a player, because a different-looking body would not make me play differently...", "When I play, I don't even see her body, but see through it and past it.\"", "Simply put, ludologists reject traditional theories of art because they claim that the artistic and socially relevant qualities of a video game are primarily determined by the underlying set of rules, demands, and expectations imposed on the player.While many games rely on emergent principles, video games commonly present simulated story worlds where emergent behavior occurs within the context of the game.", "The term \"emergent narrative\" has been used to describe how, in a simulated environment, storyline can be created simply by \"what happens to the player.\"", "However, emergent behavior is not limited to sophisticated games.", "In general, any place where event-driven instructions occur for AI in a game, emergent behavior will exist.", "For instance, take a racing game in which cars are programmed to avoid crashing, and they encounter an obstacle in the track: the cars might then maneuver to avoid the obstacle causing the cars behind them to slow or maneuver to accommodate the cars in front of them and the obstacle.", "The programmer never wrote code to specifically create a traffic jam, yet one now exists in the game.===Intellectual property for video games===Most commonly, video games are protected by copyright, though both patents and trademarks have been used as well.Though local copyright regulations vary to the degree of protection, video games qualify as copyrighted visual-audio works, and enjoy cross-country protection under the Berne Convention.", "This typically only applies to the underlying code, as well as to the artistic aspects of the game such as its writing, art assets, and music.", "Gameplay itself is generally not considered copyrightable; in the United States among other countries, video games are considered to fall into the idea–expression distinction in that it is how the game is presented and expressed to the player that can be copyrighted, but not the underlying principles of the game.Because gameplay is normally ineligible for copyright, gameplay ideas in popular games are often replicated and built upon in other games.", "At times, this repurposing of gameplay can be seen as beneficial and a fundamental part of how the industry has grown by building on the ideas of others.", "For example ''Doom'' (1993) and ''Grand Theft Auto III'' (2001) introduced gameplay that created popular new game genres, the first-person shooter and the ''Grand Theft Auto'' clone, respectively, in the few years after their release.", "However, at times and more frequently at the onset of the industry, developers would intentionally create video game clones of successful games and game hardware with few changes, which led to the flooded arcade and dedicated home console market around 1978.Cloning is also a major issue with countries that do not have strong intellectual property protection laws, such as within China.", "The lax oversight by China's government and the difficulty for foreign companies to take Chinese entities to court had enabled China to support a large grey market of cloned hardware and software systems.", "The industry remains challenged to distinguish between creating new games based on refinements of past successful games to create a new type of gameplay, and intentionally creating a clone of a game that may simply swap out art assets." ], [ "Industry", "E3 is one of the typical trade show events of the video game industry.===History===The early history of the video game industry, following the first game hardware releases and through 1983, had little structure.", "Video games quickly took off during the golden age of arcade video games from the late 1970s to early 1980s, but the newfound industry was mainly composed of game developers with little business experience.", "This led to numerous companies forming simply to create clones of popular games to try to capitalize on the market.", "Due to loss of publishing control and oversaturation of the market, the North American home video game market crashed in 1983, dropping from revenues of around in 1983 to by 1985.Many of the North American companies created in the prior years closed down.", "Japan's growing game industry was briefly shocked by this crash but had sufficient longevity to withstand the short-term effects, and Nintendo helped to revitalize the industry with the release of the Nintendo Entertainment System in North America in 1985.Along with it, Nintendo established a number of core industrial practices to prevent unlicensed game development and control game distribution on their platform, methods that continue to be used by console manufacturers today.The industry remained more conservative following the 1983 crash, forming around the concept of publisher-developer dichotomies, and by the 2000s, leading to the industry centralizing around low-risk, triple-A games and studios with large development budgets of at least or more.", "The advent of the Internet brought digital distribution as a viable means to distribute games, and contributed to the growth of more riskier, experimental independent game development as an alternative to triple-A games in the late 2000s and which has continued to grow as a significant portion of the video game industry.===Industry roles===Video games have a large network effect that draw on many different sectors that tie into the larger video game industry.", "While video game developers are a significant portion of the industry, other key participants in the market include:* Publishers: Companies generally that oversee bringing the game from the developer to market.", "This often includes performing the marketing, public relations, and advertising of the game.", "Publishers frequently pay the developers ahead of time to make their games and will be involved in critical decisions about the direction of the game's progress, and then pay the developers additional royalties or bonuses based on sales performances.", "Other smaller, boutique publishers may simply offer to perform the publishing of a game for a small fee and a portion of the sales, and otherwise leave the developer with the creative freedom to proceed.", "A range of other publisher-developer relationships exist between these points.", "* Distributors: Publishers often are able to produce their own game media and take the role of distributor, but there are also third-party distributors that can mass-produce game media and distribute to retailers.", "Digital storefronts like Steam and the iOS App Store also serve as distributors and retailers in the digital space.", "* Retailers: Physical storefronts, which include large online retailers, department and electronic stores, and specialty video game stores, sell games, consoles, and other accessories to consumers.", "This has also including a trade-in market in certain regions, allowing players to turn in used games for partial refunds or credit towards other games.", "However, with the uprising of digital marketplaces and e-commerce revolution, retailers have been performing worse than in the past.", "* Hardware manufacturers: The video game console manufacturers produce console hardware, often through a value chain system that include numerous component suppliers and contract manufacturer that assemble the consoles.", "Further, these console manufacturers typically require a license to develop for their platform and may control the production of some games, such as Nintendo does with the use of game cartridges for its systems.", "In exchange, the manufacturers may help promote games for their system and may seek console exclusivity for certain games.", "For games on personal computers, a number of manufacturers are devoted to high-performance \"gaming computer\" hardware, particularly in the graphics card area; several of the same companies overlap with component supplies for consoles.", "A range of third-party manufacturers also exist to provide equipment and gear for consoles post-sale, such as additional controllers for console or carrying cases and gear for handheld devices.", "* Journalism: While journalism around video games used to be primarily print-based, and focused more on post-release reviews and gameplay strategy, the Internet has brought a more proactive press that use web journalism, covering games in the months prior to release as well as beyond, helping to build excitement for games ahead of release.", "* Influencers: With the rising importance of social media, video game companies have found that the opinions of influencers using streaming media to play through their games has had a significant impact on game sales, and have turned to use influencers alongside traditional journalism as a means to build up attention to their game before release.", "* Esports: Esports is a major function of several multiplayer games with numerous professional leagues established since the 2000s, with large viewership numbers, particularly out of southeast Asia since the 2010s.", "* Trade and advocacy groups: Trade groups like the Entertainment Software Association were established to provide a common voice for the industry in response to governmental and other advocacy concerns.", "They frequently set up the major trade events and conventions for the industry such as E3.", "* Gamers: Proactive hobbyists who are players and consumers of video games.", "While their representation in the industry is primarily seen through game sales, many companies follow gamers' comments on social media or on user reviews and engage with them to work to improve their products in addition to other feedback from other parts of the industry.", "Demographics of the larger player community also impact parts of the market; while once dominated by younger men, the market shifted in the mid-2010s towards women and older players who generally preferred mobile and causal games, leading to further growth in those sectors.===Major regional markets===The industry itself grew out from both the United States and Japan in the 1970s and 1980s before having a larger worldwide contribution.", "Today, the video game industry is predominantly led by major companies in North America (primarily the United States and Canada), Europe, and southeast Asia including Japan, South Korea, and China.", "Hardware production remains an area dominated by Asian companies either directly involved in hardware design or part of the production process, but digital distribution and indie game development of the late 2000s has allowed game developers to flourish nearly anywhere and diversify the field.===Game sales===A retail display in Switzerland with a large selection of games for platforms popular in the early 2000sAccording to the market research firm Newzoo, the global video game industry drew estimated revenues of over in 2020.Mobile games accounted for the bulk of this, with a 48% share of the market, followed by console games at 28% and personal computer games at 23%.Sales of different types of games vary widely between countries due to local preferences.", "Japanese consumers tend to purchase much more handheld games than console games and especially PC games, with a strong preference for games catering to local tastes.", "Another key difference is that, though having declined in the West, arcade games remain an important sector of the Japanese gaming industry.", "In South Korea, computer games are generally preferred over console games, especially MMORPG games and real-time strategy games.", "Computer games are also popular in China." ], [ "Effects on society", "===Culture===''The Art of Video Games'' exhibit at the Smithsonian American Art Museum in 2012Video game culture is a worldwide new media subculture formed around video games and game playing.", "As computer and video games have increased in popularity over time, they have had a significant influence on popular culture.", "Video game culture has also evolved over time hand in hand with internet culture as well as the increasing popularity of mobile games.", "Many people who play video games identify as gamers, which can mean anything from someone who enjoys games to someone who is passionate about it.", "As video games become more social with multiplayer and online capability, gamers find themselves in growing social networks.", "Gaming can both be entertainment as well as competition, as a new trend known as electronic sports is becoming more widely accepted.", "In the 2010s, video games and discussions of video game trends and topics can be seen in social media, politics, television, film and music.", "The COVID-19 pandemic during 2020–2021 gave further visibility to video games as a pastime to enjoy with friends and family online as a means of social distancing.Since the mid-2000s there has been debate whether video games qualify as art, primarily as the form's interactivity interfered with the artistic intent of the work and that they are designed for commercial appeal.", "A significant debate on the matter came after film critic Roger Ebert published an essay \"Video Games can never be art\", which challenged the industry to prove him and other critics wrong.", "The view that video games were an art form was cemented in 2011 when the U.S. Supreme Court ruled in the landmark case ''Brown v. Entertainment Merchants Association'' that video games were a protected form of speech with artistic merit.", "Since then, video game developers have come to use the form more for artistic expression, including the development of art games, and the cultural heritage of video games as works of arts, beyond their technical capabilities, have been part of major museum exhibits, including ''The Art of Video Games'' at the Smithsonian American Art Museum and toured at other museums from 2012 to 2016.Video games will inspire sequels and other video games within the same franchise, but also have influenced works outside of the video game medium.", "Numerous television shows (both animated and live-action), films, comics and novels have been created based on existing video game franchises.", "Because video games are an interactive medium there has been trouble in converting them to these passive forms of media, and typically such works have been critically panned or treated as children's media.", "For example, until 2019, no video game film had ever been received a \"Fresh\" rating on Rotten Tomatoes, but the releases of ''Detective Pikachu'' (2019) and ''Sonic the Hedgehog'' (2020), both receiving \"Fresh\" ratings, shows signs of the film industry having found an approach to adapt video games for the large screen.", "That said, some early video game-based films have been highly successful at the box office, such as 1995's ''Mortal Kombat'' and 2001's ''Lara Croft: Tomb Raider''.More recently since the 2000s, there has also become a larger appreciation of video game music, which ranges from chiptunes composed for limited sound-output devices on early computers and consoles, to fully-scored compositions for most modern games.", "Such music has frequently served as a platform for covers and remixes, and concerts featuring video game soundtracks performed by bands or orchestras, such as ''Video Games Live'', have also become popular.", "Video games also frequently incorporate licensed music, particularly in the area of rhythm games, furthering the depth of which video games and music can work together.Further, video games can serve as a virtual environment under full control of a producer to create new works.", "With the capability to render 3D actors and settings in real-time, a new type of work machinima (short for \"machine cinema\") grew out from using video game engines to craft narratives.", "As video game engines gain higher fidelity, they have also become part of the tools used in more traditional filmmaking.", "Unreal Engine has been used as a backbone by Industrial Light & Magic for their StageCraft technology for shows like ''The Mandalorian''.Separately, video games are also frequently used as part of the promotion and marketing for other media, such as for films, anime, and comics.", "However, these licensed games in the 1990s and 2000s often had a reputation for poor quality, developed without any input from the intellectual property rights owners, and several of them are considered among lists of games with notably negative reception, such as ''Superman 64''.", "More recently, with these licensed games being developed by triple-A studios or through studios directly connected to the licensed property owner, there has been a significant improvement in the quality of these games, with an early trendsetting example of ''Batman: Arkham Asylum''.===Beneficial uses===Besides their entertainment value, appropriately-designed video games have been seen to provide value in education across several ages and comprehension levels.", "Learning principles found in video games have been identified as possible techniques with which to reform the U.S. education system.", "It has been noticed that gamers adopt an attitude while playing that is of such high concentration, they do not realize they are learning, and that if the same attitude could be adopted at school, education would enjoy significant benefits.", "Students are found to be \"learning by doing\" while playing video games while fostering creative thinking.Video games are also believed to be beneficial to the mind and body.", "It has been shown that action video game players have better hand–eye coordination and visuo-motor skills, such as their resistance to distraction, their sensitivity to information in the peripheral vision and their ability to count briefly presented objects, than nonplayers.", "Researchers found that such enhanced abilities could be acquired by training with action games, involving challenges that switch attention between different locations, but not with games requiring concentration on single objects.", "A 2018 systematic review found evidence that video gaming training had positive effects on cognitive and emotional skills in the adult population, especially with young adults.", "A 2019 systematic review also added support for the claim that video games are beneficial to the brain, although the beneficial effects of video gaming on the brain differed by video games types.How can video games boost your mental health?", "– Max Birk (Eindhoven University of Technology)Organisers of video gaming events, such as the organisers of the ''D-Lux'' video game festival in Dumfries, Scotland, have emphasised the positive aspects video games can have on mental health.", "Organisers, mental health workers and mental health nurses at the event emphasised the relationships and friendships that can be built around video games and how playing games can help people learn about others as a precursor to discussing the person's mental health.", "A study in 2020 from Oxford University also suggested that playing video games can be a benefit to a person's mental health.", "The report of 3,274 gamers, all over the age of 18, focused on the games Animal Crossing: New Horizons and Plants vs Zombies: Battle for Neighborville and used actual play-time data.", "The report found that those that played more games tended to report greater \"wellbeing\".", "Also in 2020, computer science professor Regan Mandryk of the University of Saskatchewan said her research also showed that video games can have health benefits such as reducing stress and improving mental health.", "The university's research studied all age groups – \"from pre-literate children through to older adults living in long term care homes\" – with a main focus on 18 to 55-year-olds.A study of gamers attitudes towards gaming which was reported about in 2018 found that millennials use video games as a key strategy for coping with stress.", "In the study of 1,000 gamers, 55% said that it \"helps them to unwind and relieve stress ... and half said they see the value in gaming as a method of escapism to help them deal with daily work pressures\".===Controversies===The compulsion loop for video games is believed to trigger dopamine release that can encourage addictive behavior.Video games have caused controversy since the 1970s.", "Parents and children's advocates regularly raise concerns that violent video games can influence young players into performing those violent acts in real life, and events such as the Columbine High School massacre in 1999 in which some claimed the perpetrators specifically alluded to using video games to plot out their attack, raised further fears.", "Medical experts and mental health professionals have also raised concerned that video games may be addictive, and the World Health Organization has included \"gaming disorder\" in the 11th revision of its International Statistical Classification of Diseases.", "Other health experts, including the American Psychiatric Association, have stated that there is insufficient evidence that video games can create violent tendencies or lead to addictive behavior, though agree that video games typically use a compulsion loop in their core design that can create dopamine that can help reinforce the desire to continue to play through that compulsion loop and potentially lead into violent or addictive behavior.", "Even with case law establishing that video games qualify as a protected art form, there has been pressure on the video game industry to keep their products in check to avoid over-excessive violence particularly for games aimed at younger children.", "The potential addictive behavior around games, coupled with increased used of post-sale monetization of video games, has also raised concern among parents, advocates, and government officials about gambling tendencies that may come from video games, such as controversy around the use of loot boxes in many high-profile games.Numerous other controversies around video games and its industry have arisen over the years, among the more notable incidents include the 1993 United States Congressional hearings on violent games like ''Mortal Kombat'' which lead to the formation of the ESRB ratings system, numerous legal actions taken by attorney Jack Thompson over violent games such as ''Grand Theft Auto III'' and ''Manhunt'' from 2003 to 2007, the outrage over the \"No Russian\" level from ''Call of Duty: Modern Warfare 2'' in 2009 which allowed the player to shoot a number of innocent non-player characters at an airport, and the Gamergate harassment campaign in 2014 that highlighted misogyny from a portion of the player demographic.", "The industry as a whole has also dealt with issues related to gender, racial, and LGBTQ+ discrimination and mischaracterization of these minority groups in video games.", "A further issue in the industry is related to working conditions, as development studios and publishers frequently use \"crunch time\", required extended working hours, in the weeks and months ahead of a game's release to assure on-time delivery." ], [ "Collecting and preservation", "Players of video games often maintain collections of games.", "More recently there has been interest in retrogaming, focusing on games from the first decades.", "Games in retail packaging in good shape have become collectors items for the early days of the industry, with some rare publications having gone for over .", "Separately, there is also concern about the preservation of video games, as both game media and the hardware to play them degrade over time.", "Further, many of the game developers and publishers from the first decades no longer exist, so records of their games have disappeared.", "Archivists and preservations have worked within the scope of copyright law to save these games as part of the cultural history of the industry.There are many video game museums around the world, including the National Videogame Museum in Frisco, Texas, which serves as the largest museum wholly dedicated to the display and preservation of the industry's most important artifacts.", "Europe hosts video game museums such as the Computer Games Museum in Berlin and the Museum of Soviet Arcade Machines in Moscow and Saint-Petersburg.", "The Museum of Art and Digital Entertainment in Oakland, California is a dedicated video game museum focusing on playable exhibits of console and computer games.", "The Video Game Museum of Rome is also dedicated to preserving video games and their history.", "The International Center for the History of Electronic Games at The Strong in Rochester, New York contains one of the largest collections of electronic games and game-related historical materials in the world, including a exhibit which allows guests to play their way through the history of video games.", "The Smithsonian Institution in Washington, DC has three video games on permanent display: ''Pac-Man'', ''Dragon's Lair'', and ''Pong''.The Museum of Modern Art has added a total of 20 video games and one video game console to its permanent Architecture and Design Collection since 2012.In 2012, the Smithsonian American Art Museum ran an exhibition on \"The Art of Video Games\".", "However, the reviews of the exhibit were mixed, including questioning whether video games belong in an art museum." ], [ "See also", "* Lists of video games* List of accessories to video games by system* Outline of video games" ], [ "Notes" ], [ "References" ], [ "Further reading", "* * * * * * * * * * * ''The Ultimate History of Video Games, Volume 2: Nintendo, Sony, Microsoft, and the Billion-Dollar Battle to Shape Modern Gaming'' by Steven L. Kent, Crown, 2021," ], [ "External links", "* Video games bibliography by the French video game research association ''Ludoscience''* The Virtual Museum of Computing (VMoC) (archived 10 October 2014)" ] ]

[ [ "Cambrian" ], [ "Introduction", "The '''Cambrian Period''' ( ; sometimes symbolized '''Ꞓ''') is the first geological period of the Paleozoic Era, and of the Phanerozoic Eon.", "The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period mya.", "Its subdivisions, and its base, are somewhat in flux.", "The period was established as \"Cambrian series\" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed.", "Sedgwick identified the layer as part of his task, along with Roderick Murchison, to subdivide the large \"Transition Series\", although the two geologists disagreed for a while on the appropriate categorization.", "The Cambrian is unique in its unusually high proportion of sedimentary deposits, sites of exceptional preservation where \"soft\" parts of organisms are preserved as well as their more resistant shells.", "As a result, scientific understanding of the Cambrian biology surpasses that of some later periods.The Cambrian marked a profound change in life on Earth: prior to the Cambrian, the majority of living organisms on the whole were small, unicellular, and simple (Ediacaran fauna and earlier Tonian Huainan biota being notable exceptions).", "Complex, multicellular organisms gradually became more common in the millions of years immediately preceding the Cambrian, but it was not until this period that mineralized – hence readily fossilized – organisms became common.", "The rapid diversification of lifeforms in the Cambrian, known as the Cambrian explosion, produced the first representatives of most modern animal phyla.", "Phylogenetic analysis has supported the view that before the Cambrian radiation, in the Cryogenian or Tonian, animals (metazoans) evolved monophyletically from a single common ancestor: flagellated colonial protists similar to modern choanoflagellates.Although diverse life forms prospered in the oceans, the land is thought to have been comparatively barren – with nothing more complex than a microbial soil crust and a few molluscs and arthropods (albeit not terrestrial) that emerged to browse on the microbial biofilm.", "By the end of the Cambrian, myriapods, arachnids, and hexapods started adapting to the land, along with the first plants.", "Most of the continents were probably dry and rocky due to a lack of vegetation.", "Shallow seas flanked the margins of several continents created during the breakup of the supercontinent Pannotia.", "The seas were relatively warm, and polar ice was absent for much of the period." ], [ "Stratigraphy", "The Cambrian Period followed the Ediacaran Period and preceded the Ordovician Period.The base of the Cambrian lies atop a complex assemblage of trace fossils known as the ''Treptichnus pedum'' assemblage.The use of ''Treptichnus pedum'', a reference ichnofossil to mark the lower boundary of the Cambrian, is problematic because very similar trace fossils belonging to the Treptichnids group are found well below ''T.", "pedum'' in Namibia, Spain, Newfoundland, and possibly in the western US.", "The stratigraphic range of ''T.", "pedum'' overlaps the range of the Ediacaran fossils in Namibia, and probably in Spain.=== Subdivisions ===The Cambrian is divided into four epochs (series) and ten ages (stages).", "Currently only three series and six stages are named and have a GSSP (an internationally agreed-upon stratigraphic reference point).Because the international stratigraphic subdivision is not yet complete, many local subdivisions are still widely used.", "In some of these subdivisions the Cambrian is divided into three epochs with locally differing names – the Early Cambrian (Caerfai or Waucoban, mya), Middle Cambrian (St Davids or Albertan, mya) and Late Cambrian (Merioneth or Croixan, mya).", "Trilobite zones allow biostratigraphic correlation in the Cambrian.", "Rocks of these epochs are referred to as belonging to the Lower, Middle, or Upper Cambrian.Each of the local series is divided into several stages.", "The Cambrian is divided into several regional faunal stages of which the Russian-Kazakhian system is most used in international parlance:+'''Approximate correlation of global and regional stages in Cambrian stratigraphy'''International SeriesInternational StageChineseAustralian Russian-KazakhianNorth AmericanEuropean '''Cambrian''' Furongian \"Stage 10\" Niuchehean Datsonian Batyrbaian Skullrockian / Ibexian (part) Merionethian PayntonianSunwaptan / TrempealeauanJiangshanian Jiangshanian Iverian Aksaian SakianPaibian PaibianIdamean Steptoean / Franconian MiaolingianGuzhangian Guzhangian Mindyallan Ayusokkanian Marjuman / Dresbachian Boomerangian MayanAcadian / St. David'sDrumian Wangcunian Undillian FlorianWuliuan Wuliuan Templetonian Amgan / Amgaian TopazanOrdian Delmaran Cambrian Series 2\"Stage 4\"DuyunianBranchian / Comley (part) Toyonian DyeranBotomian\"Stage 3\" Nangaoan Atdabanian MontezumanPlacentian / Comley (part) Terreneuvian\"Stage 2\"MeishucunianTommotian*BegadeanJinningianNemakit-Daldynian*Fortunian '''Ediacaran''' Sinian Adelaidean Sakharan / Vendian HadrynianMost Russian paleontologists define the lower boundary of the Cambrian at the base of the Tommotian Stage, characterized by diversification and global distribution of organisms with mineral skeletons and the appearance of the first Archaeocyath bioherms.=== Dating the Cambrian ===Archeocyathids from the Poleta formation in the Death Valley areaThe International Commission on Stratigraphy lists the Cambrian Period as beginning at and ending at .The lower boundary of the Cambrian was originally held to represent the first appearance of complex life, represented by trilobites.", "The recognition of small shelly fossils before the first trilobites, and Ediacara biota substantially earlier, has led to calls for a more precisely defined base to the Cambrian Period.Despite the long recognition of its distinction from younger Ordovician rocks and older Precambrian rocks, it was not until 1994 that the Cambrian system/period was internationally ratified.", "After decades of careful consideration, a continuous sedimentary sequence at Fortune Head, Newfoundland was settled upon as a formal base of the Cambrian Period, which was to be correlated worldwide by the earliest appearance of ''Treptichnus pedum''.", "Discovery of this fossil a few metres below the GSSP led to the refinement of this statement, and it is the ''T.", "pedum'' ichnofossil assemblage that is now formally used to correlate the base of the Cambrian.This formal designation allowed radiometric dates to be obtained from samples across the globe that corresponded to the base of the Cambrian.", "An early date of quickly gained favour, though the methods used to obtain this number are now considered to be unsuitable and inaccurate.", "A more precise date using modern radiometric dating yield a date of .", "The ash horizon in Oman from which this date was recovered corresponds to a marked fall in the abundance of carbon-13 that correlates to equivalent excursions elsewhere in the world, and to the disappearance of distinctive Ediacaran fossils (''Namacalathus'', ''Cloudina'').", "Nevertheless, there are arguments that the dated horizon in Oman does not correspond to the Ediacaran-Cambrian boundary, but represents a facies change from marine to evaporite-dominated strata – which would mean that dates from other sections, ranging from 544 to 542 Ma, are more suitable." ], [ "Paleogeography", "Plate reconstructions suggest a global supercontinent, Pannotia, was in the process of breaking up early in the Cambrian, with Laurentia (North America), Baltica, and Siberia having separated from the main supercontinent of Gondwana to form isolated land masses.", "Most continental land was clustered in the Southern Hemisphere at this time, but was drifting north.", "Large, high-velocity rotational movement of Gondwana appears to have occurred in the Early Cambrian.With a lack of sea ice – the great glaciers of the Marinoan Snowball Earth were long melted – the sea level was high, which led to large areas of the continents being flooded in warm, shallow seas ideal for sea life.", "The sea levels fluctuated somewhat, suggesting there were \"ice ages\", associated with pulses of expansion and contraction of a south polar ice cap.In Baltoscandia a Lower Cambrian transgression transformed large swathes of the Sub-Cambrian peneplain into an epicontinental sea." ], [ "Climate", "Glaciers likely existed during the earliest Cambrian at high and possibly even at middle palaeolatitudes, possibly due to the ancient continent of Gondwana covering the South Pole and cutting off polar ocean currents.", "Middle Terreneuvian deposits, corresponding to the boundary between the Fortunian and Stage 2, show evidence of glaciation.", "However, other authors believe these very early, pretrilobitic glacial deposits may not even be of Cambrian age at all but instead date back to the Neoproterozoic, an era characterised by numerous severe icehouse periods.", "The beginning of Stage 3 was relatively cool, with the period between 521 and 517 Ma being known as the Cambrian Arthropod Radiation Cool Event (CARCE).", "The Earth was generally very warm during Stage 4; its climate was comparable to the hot greenhouse of the Late Cretaceous and Early Palaeogene, as evidenced by a maximum in continental weathering rates over the last 900 million years and the presence of tropical, lateritic palaeosols at high palaeolatitudes during this time.", "The Archaecyathid Extinction Warm Event (AEWE), lasting from 511 to 510.5 Ma, was particularly warm.", "Another warm event, the Redlichiid-Olenid Extinction Warm Event, occurred at the beginning of the Wuliuan.", "It became even warmer towards the end of the period, and sea levels rose dramatically.", "This warming trend continued into the Early Ordovician, the start of which was characterised by an extremely hot global climate." ], [ "Flora", "The Cambrian flora was little different from the Ediacaran.", "The principal taxa were the marine macroalgae ''Fuxianospira'', ''Sinocylindra'', and ''Marpolia''.", "No calcareous macroalgae are known from the period.No land plant (embryophyte) fossils are known from the Cambrian.", "However, biofilms and microbial mats were well developed on Cambrian tidal flats and beaches 500 mya, and microbes forming microbial Earth ecosystems, comparable with modern soil crust of desert regions, contributing to soil formation.", "Although molecular clock estimates suggest terrestrial plants may have first emerged during the Middle or Late Cambrian, the consequent large-scale removal of the greenhouse gas CO2 from the atmosphere through sequestration did not begin until the Ordovician." ], [ "Oceanic life", "The Cambrian explosion was a period of rapid multicellular growth.", "Most animal life during the Cambrian was aquatic.", "Trilobites were once assumed to be the dominant life form at that time, but this has proven to be incorrect.", "Arthropods were by far the most dominant animals in the ocean, but trilobites were only a minor part of the total arthropod diversity.", "What made them so apparently abundant was their heavy armor reinforced by calcium carbonate (CaCO3), which fossilized far more easily than the fragile chitinous exoskeletons of other arthropods, leaving numerous preserved remains.The period marked a steep change in the diversity and composition of Earth's biosphere.", "The Ediacaran biota suffered a mass extinction at the start of the Cambrian Period, which corresponded with an increase in the abundance and complexity of burrowing behaviour.", "This behaviour had a profound and irreversible effect on the substrate which transformed the seabed ecosystems.", "Before the Cambrian, the sea floor was covered by microbial mats.", "By the end of the Cambrian, burrowing animals had destroyed the mats in many areas through bioturbation.", "As a consequence, many of those organisms that were dependent on the mats became extinct, while the other species adapted to the changed environment that now offered new ecological niches.", "Around the same time there was a seemingly rapid appearance of representatives of all the mineralized phyla, including the Bryozoa, which were once thought to have only appeared in the Lower Ordovician.", "However, many of those phyla were represented only by stem-group forms; and since mineralized phyla generally have a benthic origin, they may not be a good proxy for (more abundant) non-mineralized phyla.Margaretia dorus'' from the Burgess Shale, which were once believed to be green algae, but are now understood to represent hemichordatesWhile the early Cambrian showed such diversification that it has been named the Cambrian Explosion, this changed later in the period, when there occurred a sharp drop in biodiversity.", "About 515 million years ago, the number of species going extinct exceeded the number of new species appearing.", "Five million years later, the number of genera had dropped from an earlier peak of about 600 to just 450.Also, the speciation rate in many groups was reduced to between a fifth and a third of previous levels.", "500 million years ago, oxygen levels fell dramatically in the oceans, leading to hypoxia, while the level of poisonous hydrogen sulfide simultaneously increased, causing another extinction.", "The later half of Cambrian was surprisingly barren and showed evidence of several rapid extinction events; the stromatolites which had been replaced by reef building sponges known as Archaeocyatha, returned once more as the archaeocyathids became extinct.", "This declining trend did not change until the Great Ordovician Biodiversification Event.Some Cambrian organisms ventured onto land, producing the trace fossils ''Protichnites'' and ''Climactichnites''.", "Fossil evidence suggests that euthycarcinoids, an extinct group of arthropods, produced at least some of the ''Protichnites''.", "Fossils of the track-maker of ''Climactichnites'' have not been found; however, fossil trackways and resting traces suggest a large, slug-like mollusc.In contrast to later periods, the Cambrian fauna was somewhat restricted; free-floating organisms were rare, with the majority living on or close to the sea floor; and mineralizing animals were rarer than in future periods, in part due to the unfavourable ocean chemistry.Many modes of preservation are unique to the Cambrian, and some preserve soft body parts, resulting in an abundance of .", "These include Sirius Passet, the Sinsk Algal Lens, the Maotianshan Shales, the Emu Bay Shale, and the Burgess Shale,." ], [ "Symbol", "The United States Federal Geographic Data Committee uses a \"barred capital C\" character to represent the Cambrian Period.The Unicode character is ." ], [ "Gallery", "File:CambrianStromatolites.jpg|Stromatolites of the Pika Formation (Middle Cambrian) near Helen Lake, Banff National Park, CanadaFile:Elrathia kingii growth series.jpg|Trilobites, like these ''Elrathia kingii'' were very common arthropods during this timeFile:20191203 Anomalocaris canadensis.png|''Anomalocaris'' was an early marine predator, a member of the stem-arthropod group RadiodontaFile:20191108 Opabinia regalis.png|''Opabinia'' was a bizarre stem-arthropod that possessed five stalked eyes, and a fused proboscis tipped with a claw-like appendage.File:Pikaia NT small.jpg|''Pikaia'' was a stem-chordate from the Middle CambrianFile:Protichnites, Blackberry Hill, Wisconsin, Cambrian 2.jpg|''Protichnites'' were the trackways of arthropods that walked Cambrian beachesFile:20210830 Hallucigenia sparsa diagrammatic reconstruction.png|''Hallucigenia sparsa'' was a member of group lobopodian, that is considered to be related to modern velvet worms.File:20200329 Cambroraster falcatus.png|''Cambroraster falcatus'' was a hurdiid radiodont that bore a large horseshoe-shaped carapace.File:Amiskwia sagittiformis restoration.png|''Amiskwia sagittiformis'' was a large bodied gnathiferan from Canada and China File:Haplophrentis.png|''Haplophrentis'' was a hyolith, a group of conical shelled lophotrochozoans that were potentially related to either lophophorates or mollusks.", "File:Halkieria reconstruction.png|''Halkieria'' was a bizarre invertebrate that was an early member of the mollusk group" ], [ "See also", "* Cambrian–Ordovician extinction event – circa 488 mya* Dresbachian extinction event—circa 499 mya* End Botomian extinction event—circa 513 mya* List of fossil sites ''(with link directory)''* Type locality (geology), the locality where a particular rock type, stratigraphic unit, fossil or mineral species is first identified" ], [ "References" ], [ "Further reading", "* **** * * ****" ], [ "External links", "* * Biostratigraphy – includes information on Cambrian trilobite biostratigraphy* Sam Gon's trilobite pages (contains numerous Cambrian trilobites)* Examples of Cambrian Fossils* Paleomap Project* Report on the web on Amthor and others from ''Geology'' vol.", "31* Weird Life on the Mats* Chronostratigraphy scale v.2018/08 | Cambrian" ] ]

[ [ "Theory of categories" ], [ "Introduction", "In ontology, the '''theory of categories''' concerns itself with the ''categories of being'': the highest ''genera'' or ''kinds of entities'' according to Amie Thomasson.", "To investigate the categories of being, or simply '''categories''', is to determine the most fundamental and the broadest classes of entities.", "A distinction between such categories, in making the categories or applying them, is called an '''ontological distinction'''.", "Various systems of categories have been proposed, they often include categories for substances, properties, relations, states of affairs or events.", "A representative question within the theory of categories might articulate itself, for example, in a query like, \"Are universals prior to particulars?\"" ], [ "Early development", "The process of abstraction required to discover the number and names of the categories of being has been undertaken by many philosophers since Aristotle and involves the careful inspection of each concept to ensure that there is no higher category or categories under which that concept could be subsumed.", "The scholars of the twelfth and thirteenth centuries developed Aristotle's ideas.", "For example, Gilbert of Poitiers divides Aristotle's ten categories into two sets, primary and secondary, according to whether they inhere in the subject or not:*Primary categories: Substance, Relation, Quantity and Quality*Secondary categories: Place, Time, Situation, Condition, Action, PassionFurthermore, following Porphyry’s likening of the classificatory hierarchy to a tree, they concluded that the major classes could be subdivided to form subclasses, for example, Substance could be divided into Genus and Species, and Quality could be subdivided into Property and Accident, depending on whether the property was necessary or contingent.", "An alternative line of development was taken by Plotinus in the second century who by a process of abstraction reduced Aristotle's list of ten categories to five: Substance, Relation, Quantity, Motion and Quality.", "Plotinus further suggested that the latter three categories of his list, namely Quantity, Motion and Quality correspond to three different kinds of relation and that these three categories could therefore be subsumed under the category of Relation.", "This was to lead to the supposition that there were only two categories at the top of the hierarchical tree, namely Substance and Relation.", "Many supposed that relations only exist in the mind.", "Substance and Relation, then, are closely commutative with Matter and Mind--this is expressed most clearly in the dualism of René Descartes.===Vaisheshika======Stoic======Aristotle===One of Aristotle’s early interests lay in the classification of the natural world, how for example the genus \"animal\" could be first divided into \"two-footed animal\" and then into \"wingless, two-footed animal\".", "He realised that the distinctions were being made according to the qualities the animal possesses, the quantity of its parts and the kind of motion that it exhibits.", "To fully complete the proposition \"this animal is ...\" Aristotle stated in his work on the Categories that there were ten kinds of predicate where ...\"... each signifies either substance or quantity or quality or relation or where or when or being-in-a-position or having or acting or being acted upon\".He realised that predicates could be simple or complex.", "The simple kinds consist of a subject and a predicate linked together by the \"categorical\" or inherent type of relation.", "For Aristotle the more complex kinds were limited to propositions where the predicate is compounded of two of the above categories for example \"this is a horse running\".", "More complex kinds of proposition were only discovered after Aristotle by the Stoic, Chrysippus, who developed the \"hypothetical\" and \"disjunctive\" types of syllogism and these were terms which were to be developed through the Middle Ages and were to reappear in Kant's system of categories.", "''Category'' came into use with Aristotle's essay ''Categories'', in which he discussed univocal and equivocal terms, predication, and ten categories:*'''Substance''', essence (''ousia'') – examples of primary substance: this man, this horse; secondary substance (species, genera): man, horse*'''Quantity''' (''poson'', how much), discrete or continuous – examples: two cubits long, number, space, (length of) time.", "*'''Quality''' (''poion'', of what kind or description) – examples: white, black, grammatical, hot, sweet, curved, straight.", "*'''Relation''' (''pros ti'', toward something) – examples: double, half, large, master, knowledge.", "*'''Place''' (''pou'', where) – examples: in a marketplace, in the Lyceum*'''Time''' (''pote'', when) – examples: yesterday, last year*'''Position''', posture, attitude (''keisthai'', to lie) – examples: sitting, lying, standing*'''State''', condition (''echein'', to have or be) – examples: shod, armed*'''Action''' (''poiein'', to make or do) – examples: to lance, to heat, to cool (something)*'''Affection''', passion (''paschein'', to suffer or undergo) – examples: to be lanced, to be heated, to be cooled===Plotinus===Plotinus in writing his ''Enneads'' around AD 250 recorded that \"Philosophy at a very early age investigated the number and character of the existents ... some found ten, others less ... to some the genera were the first principles, to others only a generic classification of existents.\"", "He realised that some categories were reducible to others saying \"Why are not Beauty, Goodness and the virtues, Knowledge and Intelligence included among the primary genera?\"", "He concluded that such transcendental categories and even the categories of Aristotle were in some way posterior to the three Eleatic categories first recorded in Plato's dialogue ''Parmenides'' and which comprised the following three coupled terms: *Unity/Plurality*Motion/Stability*Identity/DifferencePlotinus called these \"the hearth of reality\" deriving from them not only the three categories of Quantity, Motion and Quality but also what came to be known as \"the three moments of the Neoplatonic world process\":*First, there existed the \"One\", and his view that \"the origin of things is a contemplation\"*The Second \"is certainly an activity ... a secondary phase ... life streaming from life ... energy running through the universe\"*The Third is some kind of Intelligence concerning which he wrote \"Activity is prior to Intellection ... and self knowledge\"Plotinus likened the three to the centre, the radii and the circumference of a circle, and clearly thought that the principles underlying the categories were the first principles of creation.", "\"From a single root all being multiplies.\"", "Similar ideas were to be introduced into Early Christian thought by, for example, Gregory of Nazianzus who summed it up saying \"Therefore, Unity, having from all eternity arrived by motion at duality, came to rest in Trinity.\"" ], [ "Modern development", "Kant and Hegel accused the Aristotelian table of categories of being 'rhapsodic', derived arbitrarily and in bulk from experience, without any systematic necessity.The early modern dualism, which has been described above, of Mind and Matter or Subject and Relation, as reflected in the writings of Descartes underwent a substantial revision in the late 18th century.", "The first objections to this stance were formulated in the eighteenth century by Immanuel Kant who realised that we can say nothing about Substance except through the relation of the subject to other things.", "For example: In the sentence \"This is a house\" the substantive subject \"house\" only gains meaning in relation to human use patterns or to other similar houses.", "The category of Substance disappears from Kant's tables, and under the heading of Relation, Kant lists ''inter alia'' the three relationship types of Disjunction, Causality and Inherence.", "The three older concepts of Quantity, Motion and Quality, as Peirce discovered, could be subsumed under these three broader headings in that Quantity relates to the subject through the relation of Disjunction; Motion relates to the subject through the relation of Causality; and Quality relates to the subject through the relation of Inherence.", "Sets of three continued to play an important part in the nineteenth century development of the categories, most notably in G.W.F.", "Hegel's extensive tabulation of categories, and in C.S.", "Peirce's categories set out in his work on the logic of relations.", "One of Peirce's contributions was to call the three primary categories Firstness, Secondness and Thirdness which both emphasises their general nature, and avoids the confusion of having the same name for both the category itself and for a concept within that category.In a separate development, and building on the notion of primary and secondary categories introduced by the Scholastics, Kant introduced the idea that secondary or \"derivative\" categories could be derived from the primary categories through the combination of one primary category with another.", "This would result in the formation of three secondary categories: the first, \"Community\" was an example that Kant gave of such a derivative category; the second, \"Modality\", introduced by Kant, was a term which Hegel, in developing Kant's dialectical method, showed could also be seen as a derivative category; and the third, \"Spirit\" or \"Will\" were terms that Hegel and Schopenhauer were developing separately for use in their own systems.", "Karl Jaspers in the twentieth century, in his development of existential categories, brought the three together, allowing for differences in terminology, as Substantiality, Communication and Will.", "This pattern of three primary and three secondary categories was used most notably in the nineteenth century by Peter Mark Roget to form the six headings of his Thesaurus of English Words and Phrases.", "The headings used were the three objective categories of Abstract Relation, Space (including Motion) and Matter and the three subjective categories of Intellect, Feeling and Volition, and he found that under these six headings all the words of the English language, and hence any possible predicate, could be assembled.===Kant===In the ''Critique of Pure Reason'' (1781), Immanuel Kant argued that the categories are part of our own mental structure and consist of a set of ''a priori'' concepts through which we interpret the world around us.", "These concepts correspond to twelve logical functions of the understanding which we use to make judgements and there are therefore two tables given in the ''Critique'', one of the Judgements and a corresponding one for the Categories.", "To give an example, the logical function behind our reasoning from ground to consequence (based on the Hypothetical relation) underlies our understanding of the world in terms of cause and effect (the Causal relation).", "In each table the number twelve arises from, firstly, an initial division into two: the Mathematical and the Dynamical; a second division of each of these headings into a further two: Quantity and Quality, and Relation and Modality respectively; and, thirdly, each of these then divides into a further three subheadings as follows.Table of JudgementsMathematical*Quantity**Universal**Particular**Singular*Quality**Affirmative**Negative**InfiniteDynamical*Relation**Categorical**Hypothetical**Disjunctive*Modality**Problematic**Assertoric**ApodicticTable of CategoriesMathematical*Quantity**Unity**Plurality**Totality*Quality**Reality**Negation**LimitationDynamical*Relation**Inherence and Subsistence (substance and accident)**Causality and Dependence (cause and effect)**Community (reciprocity)*Modality**Possibility**Existence**NecessityCriticism of Kant's system followed, firstly, by Arthur Schopenhauer, who amongst other things was unhappy with the term \"Community\", and declared that the tables \"do open violence to truth, treating it as nature was treated by old-fashioned gardeners\", and secondly, by W.T.Stace who in his book ''The Philosophy of Hegel'' suggested that in order to make Kant's structure completely symmetrical a third category would need to be added to the Mathematical and the Dynamical.", "This, he said, Hegel was to do with his category of concept.===Hegel===G.W.F.", "Hegel in his ''Science of Logic'' (1812) attempted to provide a more comprehensive system of categories than Kant and developed a structure that was almost entirely triadic.", "So important were the categories to Hegel that he claimed the first principle of the world, which he called the \"absolute\", is \"a system of categories  the categories must be the reason of which the world is a consequent\".Using his own logical method of sublation, later called the Hegelian dialectic, reasoning from the abstract through the negative to the concrete, he arrived at a hierarchy of some 270 categories, as explained by W. T. Stace.", "The three very highest categories were \"logic\", \"nature\" and \"spirit\".", "The three highest categories of \"logic\", however, he called \"being\", \"essence\", and \"notion\" which he explained as follows:* Being was differentiated from Nothing by containing with it the concept of the \"other\", an initial internal division that can be compared with Kant's category of disjunction.", "Stace called the category of Being the sphere of common sense containing concepts such as consciousness, sensation, quantity, quality and measure.", "* Essence.", "The \"other\" separates itself from the \"one\" by a kind of motion, reflected in Hegel's first synthesis of \"becoming\".", "For Stace this category represented the sphere of science containing within it firstly, the thing, its form and properties; secondly, cause, effect and reciprocity, and thirdly, the principles of classification, identity and difference.", "* Notion.", "Having passed over into the \"Other\" there is an almost neoplatonic return into a higher unity that in embracing the \"one\" and the \"other\" enables them to be considered together through their inherent qualities.", "This according to Stace is the sphere of philosophy proper where we find not only the three types of logical proposition: disjunctive, hypothetical, and categorical but also the three transcendental concepts of beauty, goodness and truth.Schopenhauer's category that corresponded with \"notion\" was that of \"idea\", which in his ''Four-Fold Root of Sufficient Reason'' he complemented with the category of the \"will\".", "The title of his major work was ''The World as Will and Idea''.", "The two other complementary categories, reflecting one of Hegel's initial divisions, were those of Being and Becoming.", "At around the same time, Goethe was developing his colour theories in the of 1810, and introduced similar principles of combination and complementation, symbolising, for Goethe, \"the primordial relations which belong both to nature and vision\".", "Hegel in his ''Science of Logic'' accordingly asks us to see his system not as a tree but as a circle." ], [ "Twentieth-century development", "In the twentieth century the primacy of the division between the subjective and the objective, or between mind and matter, was disputed by, among others, Bertrand Russell and Gilbert Ryle.", "Philosophy began to move away from the metaphysics of categorisation towards the linguistic problem of trying to differentiate between, and define, the words being used.", "Ludwig Wittgenstein’s conclusion was that there were no clear definitions which we can give to words and categories but only a \"halo\" or \"corona\" of related meanings radiating around each term.", "Gilbert Ryle thought the problem could be seen in terms of dealing with \"a galaxy of ideas\" rather than a single idea, and suggested that category mistakes are made when a concept (e.g.", "\"university\"), understood as falling under one category (e.g.", "abstract idea), is used as though it falls under another (e.g.", "physical object).", "With regard to the visual analogies being used, Peirce and Lewis, just like Plotinus earlier, likened the terms of propositions to points, and the relations between the terms to lines.", "Peirce, taking this further, talked of univalent, bivalent and trivalent relations linking predicates to their subject and it is just the number and types of relation linking subject and predicate that determine the category into which a predicate might fall.", "Primary categories contain concepts where there is one dominant kind of relation to the subject.", "Secondary categories contain concepts where there are two dominant kinds of relation.", "Examples of the latter were given by Heidegger in his two propositions \"the house is on the creek\" where the two dominant relations are spatial location (Disjunction) and cultural association (Inherence), and \"the house is eighteenth century\" where the two relations are temporal location (Causality) and cultural quality (Inherence).", "A third example may be inferred from Kant in the proposition \"the house is impressive or sublime\" where the two relations are spatial or mathematical disposition (Disjunction) and dynamic or motive power (Causality).", "Both Peirce and Wittgenstein introduced the analogy of colour theory in order to illustrate the shades of meanings of words.", "Primary categories, like primary colours, are analytical representing the furthest we can go in terms of analysis and abstraction and include Quantity, Motion and Quality.", "Secondary categories, like secondary colours, are synthetic and include concepts such as Substance, Community and Spirit.", "Apart from these, the categorial scheme of Alfred North Whitehead and his Process Philosophy, alongside Nicolai Hartmann and his Critical Realism, remain one of the most detailed and advanced systems in categorial research in metaphysics.===Peirce===Charles Sanders Peirce, who had read Kant and Hegel closely, and who also had some knowledge of Aristotle, proposed a system of merely three phenomenological categories: Firstness, Secondness, and Thirdness, which he repeatedly invoked in his subsequent writings.", "Like Hegel, C.S.", "Peirce attempted to develop a system of categories from a single indisputable principle, in Peirce's case the notion that in the first instance he could only be aware of his own ideas.", "\"It seems that the true categories of consciousness are first, feeling ... second, a sense of resistance ... and third, synthetic consciousness, or thought\".", "Elsewhere he called the three primary categories: Quality, Reaction and Meaning, and even Firstness, Secondness and Thirdness, saying, \"perhaps it is not right to call these categories conceptions, they are so intangible that they are rather tones or tints upon conceptions\": *Firstness (Quality): \"The first is predominant in feeling ... we must think of a quality without parts, e.g.", "the colour of magenta ...", "When I say it is a quality I do not mean that it \"inheres\" in a subject ...", "The whole content of consciousness is made up of qualities of feeling, as truly as the whole of space is made up of points, or the whole of time by instants\".", "*Secondness (Reaction): \"This is present even in such a rudimentary fragment of experience as a simple feeling ... an action and reaction between our soul and the stimulus ...", "The idea of second is predominant in the ideas of causation and of statical force ... the real is active; we acknowledge it by calling it the actual\".", "*Thirdness (Meaning): \"Thirdness is essentially of a general nature ... ideas in which thirdness predominate include the idea of a sign or representation ... Every genuine triadic relation involves meaning ... the idea of meaning is irreducible to those of quality and reaction ... synthetical consciousness is the consciousness of a third or medium\".Although Peirce's three categories correspond to the three concepts of relation given in Kant's tables, the sequence is now reversed and follows that given by Hegel, and indeed before Hegel of the three moments of the world-process given by Plotinus.", "Later, Peirce gave a mathematical reason for there being three categories in that although monadic, dyadic and triadic nodes are irreducible, every node of a higher valency is reducible to a \"compound of triadic relations\".", "Ferdinand de Saussure, who was developing \"semiology\" in France just as Peirce was developing \"semiotics\" in the US, likened each term of a proposition to \"the centre of a constellation, the point where other coordinate terms, the sum of which is indefinite, converge\".===Others===Edmund Husserl (1962, 2000) wrote extensively about categorial systems as part of his phenomenology.For Gilbert Ryle (1949), a category (in particular a \"category mistake\") is an important semantic concept, but one having only loose affinities to an ontological category.Contemporary systems of categories have been proposed by John G. Bennett (The Dramatic Universe, 4 vols., 1956–65), Wilfrid Sellars (1974), Reinhardt Grossmann (1983, 1992), Johansson (1989), Hoffman and Rosenkrantz (1994), Roderick Chisholm (1996), Barry Smith (ontologist) (2003), and Jonathan Lowe (2006)." ], [ "See also", "* Categories (Aristotle)* Categories (Peirce)* Categories (Stoic)* Category (Kant)* Metaphysics* Modal logic* Ontology* Schema (Kant)* Similarity (philosophy)" ], [ "References" ], [ "Selected bibliography", "*Aristotle, 1953.''", "Metaphysics''.", "Ross, W. D., trans.", "Oxford University Press.", "*--------, 2004.''", "Categories'', Edghill, E. M., trans.", "Uni.", "of Adelaide library.", "*John G. Bennett, 1956–1965.", "''The Dramatic Universe''.", "London, Hodder & Stoughton.", "*Gustav Bergmann, 1992.", "''New Foundations of Ontology''.", "Madison: Uni.", "of Wisconsin Press.", "*Browning, Douglas, 1990.", "''Ontology and the Practical Arena''.", "Pennsylvania State Uni.", "*Butchvarov, Panayot, 1979.", "''Being qua Being: A Theory of Identity, Existence, and Predication''.", "Indiana Uni.", "Press.", "*Roderick Chisholm, 1996.", "''A Realistic Theory of Categories''.", "Cambridge Uni.", "Press.", "*Feibleman, James Kern, 1951.''Ontology''.", "The Johns Hopkins Press (reprinted 1968, Greenwood Press, Publishers, New York).", "*Grossmann, Reinhardt, 1983.", "''The Categorial Structure of the World''.", "Indiana Uni.", "Press.", "*Grossmann, Reinhardt, 1992.", "''The Existence of the World: An Introduction to Ontology''.", "Routledge.", "*Haaparanta, Leila and Koskinen, Heikki J., 2012.", "''Categories of Being: Essays on Metaphysics and Logic''.", "New York: Oxford University Press.", "*Hoffman, J., and Rosenkrantz, G.", "S.,1994.", "''Substance among other Categories''.", "Cambridge Uni.", "Press.", "*Edmund Husserl, 1962.", "''Ideas: General Introduction to Pure Phenomenology''.", "Boyce Gibson, W. R., trans.", "Collier.", "*------, 2000.", "''Logical Investigations'', 2nd ed.", "Findlay, J. N., trans.", "Routledge.", "*Johansson, Ingvar, 1989.", "''Ontological Investigations''.", "Routledge, 2nd ed.", "Ontos Verlag 2004.", "* Kahn, Charles H., 2009.", "''Essays on Being'', Oxford University Press.", "*Immanuel Kant, 1998.", "''Critique of Pure Reason''.", "Guyer, Paul, and Wood, A. W., trans.", "Cambridge Uni.", "Press.", "*Charles Sanders Peirce, 1992, 1998.", "''The Essential Peirce'', vols.", "1,2.Houser, Nathan et al., eds.", "Indiana Uni.", "Press.", "*Gilbert Ryle, 1949.", "''The Concept of Mind''.", "Uni.", "of Chicago Press.", "*Wilfrid Sellars, 1974, \"Toward a Theory of the Categories\" in ''Essays in Philosophy and Its History''.", "Reidel.", "*Barry Smith, 2003.", "\"Ontology\" in ''Blackwell Guide to the Philosophy of Computing and Information''.", "Blackwell." ], [ "External links", "* Aristotle's '' Categories'' at MIT.", "* * \" Ontological Categories and How to Use Them\" – Amie Thomasson.", "* \" Recent Advances in Metaphysics\" – E. J.", "Lowe.", "* Theory and History of Ontology – Raul Corazzon." ] ]

[ [ "Concrete" ], [ "Introduction", "A single concrete block, as used for construction'''Concrete''' is a composite material composed of aggregate bonded together with a fluid cement that cures over time.", "Concrete is the second-most-used substance in the world after water, and is the most widely used building material.", "Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminium combined.When aggregate is mixed with dry Portland cement and water, the mixture forms a fluid slurry that is easily poured and molded into shape.", "The cement reacts with the water through a process called concrete hydration that hardens it over several hours to form a hard matrix that binds the materials together into a durable stone-like material that has many uses.", "This time allows concrete to not only be cast in forms, but also to have a variety of tooled processes performed.", "The hydration process is exothermic, which means ambient temperature plays a significant role in how long it takes concrete to set.", "Often, additives (such as pozzolans or superplasticizers) are included in the mixture to improve the physical properties of the wet mix, delay or accelerate the curing time, or otherwise change the finished material.", "Most concrete is poured with reinforcing materials (such as steel rebar) embedded to provide tensile strength, yielding reinforced concrete.In the past, lime based cement binders, such as lime putty, were often used but sometimes with other hydraulic cements, (water resistant) such as a calcium aluminate cement or with Portland cement to form Portland cement concrete (named for its visual resemblance to Portland stone).", "Many other non-cementitious types of concrete exist with other methods of binding aggregate together, including asphalt concrete with a bitumen binder, which is frequently used for road surfaces, and polymer concretes that use polymers as a binder.", "Concrete is distinct from mortar.", "Whereas concrete is itself a building material, mortar is a bonding agent that typically holds bricks, tiles and other masonry units together.", "Grout is another material associated with concrete and cement.", "It does not contain coarse aggregates and is usually either pourable or thixotropic, and is used to fill gaps between masonry components or coarse aggregate which has already been put in place.", "Some methods of concrete manufacture and repair involve pumping grout into the gaps to make up a solid mass ''in situ''." ], [ "Etymology", "The word concrete comes from the Latin word \"''concretus''\" (meaning compact or condensed), the perfect passive participle of \"''concrescere''\", from \"''con''-\" (together) and \"''crescere''\" (to grow)." ], [ "History", "===Ancient times===Concrete floors were found in the royal palace of Tiryns, Greece, which dates roughly to 1400-1200 BC.", "Lime mortars were used in Greece, such as in Crete and Cyprus, in 800 BC.", "The Assyrian Jerwan Aqueduct (688 BC) made use of waterproof concrete.", "Concrete was used for construction in many ancient structures.Mayan concrete at the ruins of Uxmal (850-925 A.D.) is referenced in ''Incidents of Travel in the Yucatán'' by John L. Stephens.", "\"The roof is flat and had been covered with cement\".", "\"The floors were cement, in some places hard, but, by long exposure, broken, and now crumbling under the feet.\"", "\"But throughout the wall was solid, and consisting of large stones imbedded in mortar, almost as hard as rock.", "\"Small-scale production of concrete-like materials was pioneered by the Nabatean traders who occupied and controlled a series of oases and developed a small empire in the regions of southern Syria and northern Jordan from the 4th century BC.", "They discovered the advantages of hydraulic lime, with some self-cementing properties, by 700 BC.", "They built kilns to supply mortar for the construction of rubble masonry houses, concrete floors, and underground waterproof cisterns.", "They kept the cisterns secret as these enabled the Nabataeans to thrive in the desert.", "Some of these structures survive to this day.In the Ancient Egyptian and later Roman eras, builders discovered that adding volcanic ash to lime allowed the mix to set underwater.", "They discovered the pozzolanic reaction.===Classical era===Exterior of the Roman Pantheon, finished 128 AD, the largest unreinforced concrete dome in the world.Interior of the Pantheon dome, seen from beneath.", "The concrete for the coffered dome was laid on moulds, mounted on temporary scaffolding.", "''Opus caementicium'' exposed in a characteristic Roman arch.", "In contrast to modern concrete structures, the concrete used in Roman buildings was usually covered with brick or stone.The Romans used concrete extensively from 300 BCE to 476 CE.", "During the Roman Empire, Roman concrete (or ''opus caementicium'') was made from quicklime, pozzolana and an aggregate of pumice.", "Its widespread use in many Roman structures, a key event in the history of architecture termed the Roman architectural revolution, freed Roman construction from the restrictions of stone and brick materials.", "It enabled revolutionary new designs in terms of both structural complexity and dimension.", "The Colosseum in Rome was built largely of concrete, and the Pantheon has the world's largest unreinforced concrete dome.Concrete, as the Romans knew it, was a new and revolutionary material.", "Laid in the shape of arches, vaults and domes, it quickly hardened into a rigid mass, free from many of the internal thrusts and strains that troubled the builders of similar structures in stone or brick.Modern tests show that ''opus caementicium'' had as much compressive strength as modern Portland-cement concrete (ca.", ").", "However, due to the absence of reinforcement, its tensile strength was far lower than modern reinforced concrete, and its mode of application also differed:Modern structural concrete differs from Roman concrete in two important details.", "First, its mix consistency is fluid and homogeneous, allowing it to be poured into forms rather than requiring hand-layering together with the placement of aggregate, which, in Roman practice, often consisted of rubble.", "Second, integral reinforcing steel gives modern concrete assemblies great strength in tension, whereas Roman concrete could depend only upon the strength of the concrete bonding to resist tension.The long-term durability of Roman concrete structures has been found to be due to its use of pyroclastic (volcanic) rock and ash, whereby the crystallization of strätlingite (a specific and complex calcium aluminosilicate hydrate) and the coalescence of this and similar calcium–aluminium-silicate–hydrate cementing binders helped give the concrete a greater degree of fracture resistance even in seismically active environments.", "Roman concrete is significantly more resistant to erosion by seawater than modern concrete; it used pyroclastic materials which react with seawater to form Al-tobermorite crystals over time.", "The use of hot mixing and the presence of lime clasts are thought to give the concrete a self-healing ability, where cracks that form become filled with calcite that prevents the crack from spreading.The widespread use of concrete in many Roman structures ensured that many survive to the present day.", "The Baths of Caracalla in Rome are just one example.", "Many Roman aqueducts and bridges, such as the magnificent Pont du Gard in southern France, have masonry cladding on a concrete core, as does the dome of the Pantheon.===Middle Ages===After the Roman Empire, the use of burned lime and pozzolana was greatly reduced.", "Low kiln temperatures in the burning of lime, lack of pozzolana, and poor mixing all contributed to a decline in the quality of concrete and mortar.", "From the 11th century, the increased use of stone in church and castle construction led to an increased demand for mortar.", "Quality began to improve in the 12th century through better grinding and sieving.", "Medieval lime mortars and concretes were non-hydraulic and were used for binding masonry, \"hearting\" (binding rubble masonry cores) and foundations.", "Bartholomaeus Anglicus in his ''De proprietatibus rerum'' (1240) describes the making of mortar.", "In an English translation from 1397, it reads \"lyme ... is a stone brent; by medlynge thereof with sonde and water sement is made\".", "From the 14th century, the quality of mortar was again excellent, but only from the 17th century was pozzolana commonly added.The ''Canal du Midi'' was built using concrete in 1670.===Industrial era===Smeaton's Tower in Devon, EnglandPerhaps the greatest step forward in the modern use of concrete was Smeaton's Tower, built by British engineer John Smeaton in Devon, England, between 1756 and 1759.This third Eddystone Lighthouse pioneered the use of hydraulic lime in concrete, using pebbles and powdered brick as aggregate.A method for producing Portland cement was developed in England and patented by Joseph Aspdin in 1824.Aspdin chose the name for its similarity to Portland stone, which was quarried on the Isle of Portland in Dorset, England.", "His son William continued developments into the 1840s, earning him recognition for the development of \"modern\" Portland cement.Reinforced concrete was invented in 1849 by Joseph Monier.", "and the first reinforced concrete house was built by François Coignet in 1853.The first concrete reinforced bridge was designed and built by Joseph Monier in 1875.Prestressed concrete and post-tensioned concrete were pioneered by Eugène Freyssinet, a French structural and civil engineer.", "Concrete components or structures are compressed by tendon cables during, or after, their fabrication in order to strengthen them against tensile forces developing when put in service.", "Freyssinet patented the technique on 2 October 1928." ], [ "Composition", "Concrete is an artificial composite material, comprising a matrix of cementitious binder (typically Portland cement paste or asphalt) and a dispersed phase or \"filler\" of aggregate (typically a rocky material, loose stones, and sand).", "The binder \"glues\" the filler together to form a synthetic conglomerate.", "Many types of concrete are available, determined by the formulations of binders and the types of aggregate used to suit the application of the engineered material.", "These variables determine strength and density, as well as chemical and thermal resistance of the finished product.Cross section of a concrete railway sleeper below a railConstruction aggregates consist of large chunks of material in a concrete mix, generally a coarse gravel or crushed rocks such as limestone, or granite, along with finer materials such as sand.Cement paste, most commonly made of Portland cement, is the most prevalent kind of concrete binder.", "For cementitious binders, water is mixed with the dry cement powder and aggregate, which produces a semi-liquid slurry (paste) that can be shaped, typically by pouring it into a form.", "The concrete solidifies and hardens through a chemical process called hydration.", "The water reacts with the cement, which bonds the other components together, creating a robust, stone-like material.", "Other cementitious materials, such as fly ash and slag cement, are sometimes added—either pre-blended with the cement or directly as a concrete component—and become a part of the binder for the aggregate.", "Fly ash and slag can enhance some properties of concrete such as fresh properties and durability.", "Alternatively, other materials can also be used as a concrete binder: the most prevalent substitute is asphalt, which is used as the binder in asphalt concrete.Admixtures are added to modify the cure rate or properties of the material.", "Mineral admixtures use recycled materials as concrete ingredients.", "Conspicuous materials include fly ash, a by-product of coal-fired power plants; ground granulated blast furnace slag, a by-product of steelmaking; and silica fume, a by-product of industrial electric arc furnaces.Structures employing Portland cement concrete usually include steel reinforcement because this type of concrete can be formulated with high compressive strength, but always has lower tensile strength.", "Therefore, it is usually reinforced with materials that are strong in tension, typically steel rebar.The ''mix design'' depends on the type of structure being built, how the concrete is mixed and delivered, and how it is placed to form the structure.===Cement===Several tons of bagged cement, about two minutes of output from a 10,000 ton per day cement kilnPortland cement is the most common type of cement in general usage.", "It is a basic ingredient of concrete, mortar, and many plasters.", "It consists of a mixture of calcium silicates (alite, belite), aluminates and ferrites—compounds, which will react with water.", "Portland cement and similar materials are made by heating limestone (a source of calcium) with clay or shale (a source of silicon, aluminium and iron) and grinding this product (called ''clinker'') with a source of sulfate (most commonly gypsum).Cement kilns are extremely large, complex, and inherently dusty industrial installations.", "Of the various ingredients used to produce a given quantity of concrete, the cement is the most energetically expensive.", "Even complex and efficient kilns require 3.3 to 3.6 gigajoules of energy to produce a ton of clinker and then grind it into cement.", "Many kilns can be fueled with difficult-to-dispose-of wastes, the most common being used tires.", "The extremely high temperatures and long periods of time at those temperatures allows cement kilns to efficiently and completely burn even difficult-to-use fuels.", "The five major compounds of calcium silicates and aluminates comprising Portland cement range from 5 to 50% in weight.===Curing===Combining water with a cementitious material forms a cement paste by the process of hydration.", "The cement paste glues the aggregate together, fills voids within it, and makes it flow more freely.As stated by Abrams' law, a lower water-to-cement ratio yields a stronger, more durable concrete, whereas more water gives a freer-flowing concrete with a higher slump.", "The hydration of cement involves many concurrent reactions.", "The process involves polymerization, the interlinking of the silicates and aluminate components as well as their bonding to sand and gravel particles to form a solid mass.", "One illustrative conversion is the hydration of tricalcium silicate:: Cement chemist notation: C3S + H → C-S-H + CH + heat: Standard notation: Ca3SiO5 + H2O → CaO・SiO2・H2O (gel) + Ca(OH)2 + heat: Balanced: 2 Ca3SiO5 + 7 H2O → 3 CaO・2 SiO2・4 H2O (gel) + 3 Ca(OH)2 + heat: (approximately as the exact ratios of CaO, SiO2 and H2O in C-S-H can vary)The hydration (curing) of cement is irreversible.===Aggregates===aggregatesFine and coarse aggregates make up the bulk of a concrete mixture.", "Sand, natural gravel, and crushed stone are used mainly for this purpose.", "Recycled aggregates (from construction, demolition, and excavation waste) are increasingly used as partial replacements for natural aggregates, while a number of manufactured aggregates, including air-cooled blast furnace slag and bottom ash are also permitted.The size distribution of the aggregate determines how much binder is required.", "Aggregate with a very even size distribution has the biggest gaps whereas adding aggregate with smaller particles tends to fill these gaps.", "The binder must fill the gaps between the aggregate as well as paste the surfaces of the aggregate together, and is typically the most expensive component.", "Thus, variation in sizes of the aggregate reduces the cost of concrete.", "The aggregate is nearly always stronger than the binder, so its use does not negatively affect the strength of the concrete.Redistribution of aggregates after compaction often creates non-homogeneity due to the influence of vibration.", "This can lead to strength gradients.Decorative stones such as quartzite, small river stones or crushed glass are sometimes added to the surface of concrete for a decorative \"exposed aggregate\" finish, popular among landscape designers.===Admixtures===Admixtures are materials in the form of powder or fluids that are added to the concrete to give it certain characteristics not obtainable with plain concrete mixes.", "Admixtures are defined as additions \"made as the concrete mix is being prepared\".", "The most common admixtures are retarders and accelerators.", "In normal use, admixture dosages are less than 5% by mass of cement and are added to the concrete at the time of batching/mixing.", "(See below.)", "The common types of admixtures are as follows:* Accelerators speed up the hydration (hardening) of the concrete.", "Typical materials used are calcium chloride, calcium nitrate and sodium nitrate.", "However, use of chlorides may cause corrosion in steel reinforcing and is prohibited in some countries, so that nitrates may be favored, even though they are less effective than the chloride salt.", "Accelerating admixtures are especially useful for modifying the properties of concrete in cold weather.", "* Air entraining agents add and entrain tiny air bubbles in the concrete, which reduces damage during freeze-thaw cycles, increasing durability.", "However, entrained air entails a tradeoff with strength, as each 1% of air may decrease compressive strength by 5%.", "If too much air becomes trapped in the concrete as a result of the mixing process, defoamers can be used to encourage the air bubble to agglomerate, rise to the surface of the wet concrete and then disperse.", "* Bonding agents are used to create a bond between old and new concrete (typically a type of polymer) with wide temperature tolerance and corrosion resistance.", "* Corrosion inhibitors are used to minimize the corrosion of steel and steel bars in concrete.", "* Crystalline admixtures are typically added during batching of the concrete to lower permeability.", "The reaction takes place when exposed to water and un-hydrated cement particles to form insoluble needle-shaped crystals, which fill capillary pores and micro-cracks in the concrete to block pathways for water and waterborne contaminates.", "Concrete with crystalline admixture can expect to self-seal as constant exposure to water will continuously initiate crystallization to ensure permanent waterproof protection.", "* Pigments can be used to change the color of concrete, for aesthetics.", "* Plasticizers increase the workability of plastic, or \"fresh\", concrete, allowing it to be placed more easily, with less consolidating effort.", "A typical plasticizer is lignosulfonate.", "Plasticizers can be used to reduce the water content of a concrete while maintaining workability and are sometimes called water-reducers due to this use.", "Such treatment improves its strength and durability characteristics.", "* Superplasticizers (also called high-range water-reducers) are a class of plasticizers that have fewer deleterious effects and can be used to increase workability more than is practical with traditional plasticizers.", "Superplasticizers are used to increase compressive strength.", "It increases the workability of the concrete and lowers the need for water content by 15–30%.", "* Pumping aids improve pumpability, thicken the paste and reduce separation and bleeding.", "* Retarders slow the hydration of concrete and are used in large or difficult pours where partial setting is undesirable before completion of the pour.", "Typical polyol retarders are sugar, sucrose, sodium gluconate, glucose, citric acid, and tartaric acid.===Mineral admixtures and blended cements===Inorganic materials that have pozzolanic or latent hydraulic properties, these very fine-grained materials are added to the concrete mix to improve the properties of concrete (mineral admixtures), or as a replacement for Portland cement (blended cements).", "Products which incorporate limestone, fly ash, blast furnace slag, and other useful materials with pozzolanic properties into the mix, are being tested and used.", "These developments are ever growing in relevance to minimize the impacts caused by cement use, notorious for being one of the largest producers (at about 5 to 10%) of global greenhouse gas emissions.", "The use of alternative materials also is capable of lowering costs, improving concrete properties, and recycling wastes, the latest being relevant for circular economy aspects of the construction industry, whose demand is ever growing with greater impacts on raw material extraction, waste generation and landfill practices.", "* Fly ash: A by-product of coal-fired electric generating plants, it is used to partially replace Portland cement (by up to 60% by mass).", "The properties of fly ash depend on the type of coal burnt.", "In general, siliceous fly ash is pozzolanic, while calcareous fly ash has latent hydraulic properties.", "* Ground granulated blast furnace slag (GGBFS or GGBS): A by-product of steel production is used to partially replace Portland cement (by up to 80% by mass).", "It has latent hydraulic properties.", "* Silica fume: A by-product of the production of silicon and ferrosilicon alloys.", "Silica fume is similar to fly ash, but has a particle size 100 times smaller.", "This results in a higher surface-to-volume ratio and a much faster pozzolanic reaction.", "Silica fume is used to increase strength and durability of concrete, but generally requires the use of superplasticizers for workability.", "* High reactivity metakaolin (HRM): Metakaolin produces concrete with strength and durability similar to concrete made with silica fume.", "While silica fume is usually dark gray or black in color, high-reactivity metakaolin is usually bright white in color, making it the preferred choice for architectural concrete where appearance is important.", "* Carbon nanofibers can be added to concrete to enhance compressive strength and gain a higher Young's modulus, and also to improve the electrical properties required for strain monitoring, damage evaluation and self-health monitoring of concrete.", "Carbon fiber has many advantages in terms of mechanical and electrical properties (e.g., higher strength) and self-monitoring behavior due to the high tensile strength and high electrical conductivity.", "* Carbon products have been added to make concrete electrically conductive, for deicing purposes.", "* New research from Japan's University of Kitakyushu shows that a washed and dried recycled mix of used diapers can be an environmental solution to producing less landfill and using less sand in concrete production.", "A model home was built in Indonesia to test the strength and durability of the new diaper-cement composite." ], [ "Production", "Concrete plant showing a concrete mixer being filled from ingredient silosBirmingham, Alabama, in 1936Concrete production is the process of mixing together the various ingredients—water, aggregate, cement, and any additives—to produce concrete.", "Concrete production is time-sensitive.", "Once the ingredients are mixed, workers must put the concrete in place before it hardens.", "In modern usage, most concrete production takes place in a large type of industrial facility called a concrete plant, or often a batch plant.", "The usual method of placement is casting in formwork, which holds the mix in shape until it has set enough to hold its shape unaided.Concrete plants come in two main types, ready-mix plants and central mix plants.", "A ready-mix plant blends all of the solid ingredients, while a central mix does the same but adds water.", "A central-mix plant offers more precise control of the concrete quality.", "Central mix plants must be close to the work site where the concrete will be used, since hydration begins at the plant.A concrete plant consists of large hoppers for storage of various ingredients like cement, storage for bulk ingredients like aggregate and water, mechanisms for the addition of various additives and amendments, machinery to accurately weigh, move, and mix some or all of those ingredients, and facilities to dispense the mixed concrete, often to a concrete mixer truck.Modern concrete is usually prepared as a viscous fluid, so that it may be poured into forms.", "The forms are containers that define the desired shape.", "Concrete formwork can be prepared in several ways, such as slip forming and steel plate construction.", "Alternatively, concrete can be mixed into dryer, non-fluid forms and used in factory settings to manufacture precast concrete products.Interruption in pouring the concrete can cause the initially placed material to begin to set before the next batch is added on top.", "This creates a horizontal plane of weakness called a ''cold joint'' between the two batches.", "Once the mix is where it should be, the curing process must be controlled to ensure that the concrete attains the desired attributes.", "During concrete preparation, various technical details may affect the quality and nature of the product.===Design mix===''Design mix'' ratios are decided by an engineer after analyzing the properties of the specific ingredients being used.", "Instead of using a 'nominal mix' of 1 part cement, 2 parts sand, and 4 parts aggregate (the second example from above), a civil engineer will custom-design a concrete mix to exactly meet the requirements of the site and conditions, setting material ratios and often designing an admixture package to fine-tune the properties or increase the performance envelope of the mix.", "Design-mix concrete can have very broad specifications that cannot be met with more basic nominal mixes, but the involvement of the engineer often increases the cost of the concrete mix.Concrete Mixes are primarily divided into nominal mix, standard mix and design mix.Nominal mix ratios are given in volume of .", "Nominal mixes are a simple, fast way of getting a basic idea of the properties of the finished concrete without having to perform testing in advance.Various governing bodies (such as British Standards) define nominal mix ratios into a number of grades, usually ranging from lower compressive strength to higher compressive strength.", "The grades usually indicate the 28-day cube strength.===Mixing===Thorough mixing is essential to produce uniform, high-quality concrete.", "has shown that the mixing of cement and water into a paste before combining these materials with aggregates can increase the compressive strength of the resulting concrete.", "The paste is generally mixed in a , shear-type mixer at a w/c (water to cement ratio) of 0.30 to 0.45 by mass.", "The cement paste premix may include admixtures such as accelerators or retarders, superplasticizers, pigments, or silica fume.", "The premixed paste is then blended with aggregates and any remaining batch water and final mixing is completed in conventional concrete mixing equipment.===Sample analysis – Workability===Concrete floor of a parking garage being placedPouring and smoothing out concrete at Palisades Park in Washington, DCWorkability is the ability of a fresh (plastic) concrete mix to fill the form/mold properly with the desired work (pouring, pumping, spreading, tamping, vibration) and without reducing the concrete's quality.", "Workability depends on water content, aggregate (shape and size distribution), cementitious content and age (level of hydration) and can be modified by adding chemical admixtures, like superplasticizer.", "Raising the water content or adding chemical admixtures increases concrete workability.", "Excessive water leads to increased bleeding or segregation of aggregates (when the cement and aggregates start to separate), with the resulting concrete having reduced quality.", "Changes in gradation can also affect workability of the concrete, although a wide range of gradation can be used for various applications.", "An undesirable gradation can mean using a large aggregate that is too large for the size of the formwork, or which has too few smaller aggregate grades to serve to fill the gaps between the larger grades, or using too little or too much sand for the same reason, or using too little water, or too much cement, or even using jagged crushed stone instead of smoother round aggregate such as pebbles.", "Any combination of these factors and others may result in a mix which is too harsh, i.e., which does not flow or spread out smoothly, is difficult to get into the formwork, and which is difficult to surface finish.Workability can be measured by the concrete slump test, a simple measure of the plasticity of a fresh batch of concrete following the ASTM C 143 or EN 12350-2 test standards.", "Slump is normally measured by filling an \"Abrams cone\" with a sample from a fresh batch of concrete.", "The cone is placed with the wide end down onto a level, non-absorptive surface.", "It is then filled in three layers of equal volume, with each layer being tamped with a steel rod to consolidate the layer.", "When the cone is carefully lifted off, the enclosed material slumps a certain amount, owing to gravity.", "A relatively dry sample slumps very little, having a slump value of one or two inches (25 or 50 mm) out of .", "A relatively wet concrete sample may slump as much as eight inches.", "Workability can also be measured by the flow table test.Slump can be increased by addition of chemical admixtures such as plasticizer or superplasticizer without changing the water-cement ratio.", "Some other admixtures, especially air-entraining admixture, can increase the slump of a mix.High-flow concrete, like self-consolidating concrete, is tested by other flow-measuring methods.", "One of these methods includes placing the cone on the narrow end and observing how the mix flows through the cone while it is gradually lifted.After mixing, concrete is a fluid and can be pumped to the location where needed.===Curing===A concrete slab being kept hydrated during water curing by submersion (ponding)====Maintaining optimal conditions for cement hydration====Concrete must be kept moist during curing in order to achieve optimal strength and durability.", "During curing hydration occurs, allowing calcium-silicate hydrate (C-S-H) to form.", "Over 90% of a mix's final strength is typically reached within four weeks, with the remaining 10% achieved over years or even decades.", "The conversion of calcium hydroxide in the concrete into calcium carbonate from absorption of CO2 over several decades further strengthens the concrete and makes it more resistant to damage.", "This carbonation reaction, however, lowers the pH of the cement pore solution and can corrode the reinforcement bars.Hydration and hardening of concrete during the first three days is critical.", "Abnormally fast drying and shrinkage due to factors such as evaporation from wind during placement may lead to increased tensile stresses at a time when it has not yet gained sufficient strength, resulting in greater shrinkage cracking.", "The early strength of the concrete can be increased if it is kept damp during the curing process.", "Minimizing stress prior to curing minimizes cracking.", "High-early-strength concrete is designed to hydrate faster, often by increased use of cement that increases shrinkage and cracking.", "The strength of concrete changes (increases) for up to three years.", "It depends on cross-section dimension of elements and conditions of structure exploitation.", "Addition of short-cut polymer fibers can improve (reduce) shrinkage-induced stresses during curing and increase early and ultimate compression strength.Properly curing concrete leads to increased strength and lower permeability and avoids cracking where the surface dries out prematurely.", "Care must also be taken to avoid freezing or overheating due to the exothermic setting of cement.", "Improper curing can cause scaling, reduced strength, poor abrasion resistance and cracking.====Curing techniques avoiding water loss by evaporation====During the curing period, concrete is ideally maintained at controlled temperature and humidity.", "To ensure full hydration during curing, concrete slabs are often sprayed with \"curing compounds\" that create a water-retaining film over the concrete.", "Typical films are made of wax or related hydrophobic compounds.", "After the concrete is sufficiently cured, the film is allowed to abrade from the concrete through normal use.Traditional conditions for curing involve spraying or ponding the concrete surface with water.", "The adjacent picture shows one of many ways to achieve this, ponding—submerging setting concrete in water and wrapping in plastic to prevent dehydration.", "Additional common curing methods include wet burlap and plastic sheeting covering the fresh concrete.For higher-strength applications, accelerated curing techniques may be applied to the concrete.", "A common technique involves heating the poured concrete with steam, which serves to both keep it damp and raise the temperature so that the hydration process proceeds more quickly and more thoroughly." ], [ "Alternative types", "===Asphalt===''Asphalt concrete'' (commonly called ''asphalt'', ''blacktop'', or ''pavement'' in North America, and ''tarmac'', ''bitumen macadam'', or ''rolled asphalt'' in the United Kingdom and the Republic of Ireland) is a composite material commonly used to surface roads, parking lots, airports, as well as the core of embankment dams.", "Asphalt mixtures have been used in pavement construction since the beginning of the twentieth century.", "It consists of mineral aggregate bound together with asphalt, laid in layers, and compacted.", "The process was refined and enhanced by Belgian inventor and U.S. immigrant Edward De Smedt.The terms ''asphalt'' (or ''asphaltic'') ''concrete'', ''bituminous asphalt concrete'', and ''bituminous mixture'' are typically used only in engineering and construction documents, which define concrete as any composite material composed of mineral aggregate adhered with a binder.", "The abbreviation, ''AC'', is sometimes used for ''asphalt concrete'' but can also denote ''asphalt content'' or ''asphalt cement'', referring to the liquid asphalt portion of the composite material.=== Graphene enhanced concrete ===Graphene enhanced concretes are standard designs of concrete mixes, except that during the cement-mixing or production process, a small amount of chemically engineered graphene is added.", "These enhanced graphene concretes are designed around the concrete application.=== Microbial ===Bacteria such as ''Bacillus pasteurii'', ''Bacillus pseudofirmus'', ''Bacillus cohnii'', ''Sporosarcina pasteuri'', and ''Arthrobacter crystallopoietes'' increase the compression strength of concrete through their biomass.", "However some forms of bacteria can also be concrete-destroying.", "Bacillus sp.", "CT-5.can reduce corrosion of reinforcement in reinforced concrete by up to four times.", "''Sporosarcina pasteurii'' reduces water and chloride permeability.", "''B.", "pasteurii'' increases resistance to acid.", "''Bacillus pasteurii'' and ''B.", "sphaericuscan'' induce calcium carbonate precipitation in the surface of cracks, adding compression strength.=== Nanoconcrete ===Decorative plate made of Nano concrete with High-Energy Mixing (HEM)Nanoconcrete (also spelled \"nano concrete\"' or \"nano-concrete\") is a class of materials that contains Portland cement particles that are no greater than 100 μm and particles of silica no greater than 500 μm, which fill voids that would otherwise occur in normal concrete, thereby substantially increasing the material's strength.", "It is widely used in foot and highway bridges where high flexural and compressive strength are indicated.=== Pervious ===Pervious concrete is a mix of specially graded coarse aggregate, cement, water, and little-to-no fine aggregates.", "This concrete is also known as \"no-fines\" or porous concrete.", "Mixing the ingredients in a carefully controlled process creates a paste that coats and bonds the aggregate particles.", "The hardened concrete contains interconnected air voids totaling approximately 15 to 25 percent.", "Water runs through the voids in the pavement to the soil underneath.", "Air entrainment admixtures are often used in freeze-thaw climates to minimize the possibility of frost damage.", "Pervious concrete also permits rainwater to filter through roads and parking lots, to recharge aquifers, instead of contributing to runoff and flooding.=== Polymer ===Polymer concretes are mixtures of aggregate and any of various polymers and may be reinforced.", "The cement is costlier than lime-based cements, but polymer concretes nevertheless have advantages; they have significant tensile strength even without reinforcement, and they are largely impervious to water.", "Polymer concretes are frequently used for the repair and construction of other applications, such as drains.=== Volcanic ===Volcanic concrete substitutes volcanic rock for the limestone that is burned to form clinker.", "It consumes a similar amount of energy, but does not directly emit carbon as a byproduct.", "Volcanic rock/ash are used as supplementary cementitious materials in concrete to improve the resistance to sulfate, chloride and alkali silica reaction due to pore refinement.", "Also, they are generally cost effective in comparison to other aggregates, good for semi and light weight concretes, and good for thermal and acoustic insulation.Pyroclastic materials, such as pumice, scoria, and ashes are formed from cooling magma during explosive volcanic eruptions.", "They are used as supplementary cementitious materials (SCM) or as aggregates for cements and concretes.", "They have been extensively used since ancient times to produce materials for building applications.", "For example, pumice and other volcanic glasses were added as a natural pozzolanic material for mortars and plasters during the construction of the Villa San Marco in the Roman period (89 BC – 79 AD), which remain one of the best-preserved otium villae of the Bay of Naples in Italy.===Waste light===Waste light is form of polymer modified concrete.", "The specific polymer admixture allows the replacement of all the traditional aggregates (gravel, sand, stone) by any mixture of solid waste materials in the grain size of 3–10 mm to form a low-compressive-strength (3–20 N/mm2) product for road and building construction.", "One cubic meter of waste light concrete contains 1.1–1.3 m3 of shredded waste and no other aggregates.=== Sulfur concrete ===Sulfur concrete is a special concrete that uses sulfur as a binder and does not require cement or water." ], [ "Properties", "Concrete has relatively high compressive strength, but much lower tensile strength.", "Therefore, it is usually reinforced with materials that are strong in tension (often steel).", "The elasticity of concrete is relatively constant at low stress levels but starts decreasing at higher stress levels as matrix cracking develops.", "Concrete has a very low coefficient of thermal expansion and shrinks as it matures.", "All concrete structures crack to some extent, due to shrinkage and tension.", "Concrete that is subjected to long-duration forces is prone to creep.Tests can be performed to ensure that the properties of concrete correspond to specifications for the application.Compression testing of a concrete cylinderThe ingredients affect the strengths of the material.", "Concrete strength values are usually specified as the lower-bound compressive strength of either a cylindrical or cubic specimen as determined by standard test procedures.The strengths of concrete is dictated by its function.", "Very low-strength— or less—concrete may be used when the concrete must be lightweight.", "Lightweight concrete is often achieved by adding air, foams, or lightweight aggregates, with the side effect that the strength is reduced.", "For most routine uses, concrete is often used.", "concrete is readily commercially available as a more durable, although more expensive, option.", "Higher-strength concrete is often used for larger civil projects.", "Strengths above are often used for specific building elements.", "For example, the lower floor columns of high-rise concrete buildings may use concrete of or more, to keep the size of the columns small.", "Bridges may use long beams of high-strength concrete to lower the number of spans required.", "Occasionally, other structural needs may require high-strength concrete.", "If a structure must be very rigid, concrete of very high strength may be specified, even much stronger than is required to bear the service loads.", "Strengths as high as have been used commercially for these reasons.===Energy efficiency===The cement produced for making concrete accounts for about 8% of worldwide emissions per year (compared to, ''e.g.", "'', global aviation at 1.9%).", "The two largest sources of are produced by the cement manufacturing process, arising from (1) the decarbonation reaction of limestone in the cement kiln (T ≈ 950 °C), and (2) from the combustion of fossil fuel to reach the sintering temperature (T ≈ 1450 °C) of cement clinker in the kiln.", "The energy required for extracting, crushing, and mixing the raw materials (construction aggregates used in the concrete production, and also limestone and clay feeding the cement kiln) is lower.", "Energy requirement for transportation of ready-mix concrete is also lower because it is produced nearby the construction site from local resources, typically manufactured within 100 kilometers of the job site.", "The overall embodied energy of concrete at roughly 1 to 1.5 megajoules per kilogram is therefore lower than for many structural and construction materials.Once in place, concrete offers a great energy efficiency over the lifetime of a building.", "Concrete walls leak air far less than those made of wood frames.", "Air leakage accounts for a large percentage of energy loss from a home.", "The thermal mass properties of concrete increase the efficiency of both residential and commercial buildings.", "By storing and releasing the energy needed for heating or cooling, concrete's thermal mass delivers year-round benefits by reducing temperature swings inside and minimizing heating and cooling costs.", "While insulation reduces energy loss through the building envelope, thermal mass uses walls to store and release energy.", "Modern concrete wall systems use both external insulation and thermal mass to create an energy-efficient building.", "Insulating concrete forms (ICFs) are hollow blocks or panels made of either insulating foam or rastra that are stacked to form the shape of the walls of a building and then filled with reinforced concrete to create the structure.===Fire safety===Boston City Hall (1968) is a Brutalist design constructed largely of precast and poured in place concrete.Concrete buildings are more resistant to fire than those constructed using steel frames, since concrete has lower heat conductivity than steel and can thus last longer under the same fire conditions.", "Concrete is sometimes used as a fire protection for steel frames, for the same effect as above.", "Concrete as a fire shield, for example Fondu fyre, can also be used in extreme environments like a missile launch pad.Options for non-combustible construction include floors, ceilings and roofs made of cast-in-place and hollow-core precast concrete.", "For walls, concrete masonry technology and Insulating Concrete Forms (ICFs) are additional options.", "ICFs are hollow blocks or panels made of fireproof insulating foam that are stacked to form the shape of the walls of a building and then filled with reinforced concrete to create the structure.Concrete also provides good resistance against externally applied forces such as high winds, hurricanes, and tornadoes owing to its lateral stiffness, which results in minimal horizontal movement.", "However, this stiffness can work against certain types of concrete structures, particularly where a relatively higher flexing structure is required to resist more extreme forces.===Earthquake safety===As discussed above, concrete is very strong in compression, but weak in tension.", "Larger earthquakes can generate very large shear loads on structures.", "These shear loads subject the structure to both tensile and compressional loads.", "Concrete structures without reinforcement, like other unreinforced masonry structures, can fail during severe earthquake shaking.", "Unreinforced masonry structures constitute one of the largest earthquake risks globally.", "These risks can be reduced through seismic retrofitting of at-risk buildings, (e.g.", "school buildings in Istanbul, Turkey)." ], [ "Construction with concrete", "City Court Building in Buffalo, New YorkConcrete is one of the most durable building materials.", "It provides superior fire resistance compared with wooden construction and gains strength over time.", "Structures made of concrete can have a long service life.", "Concrete is used more than any other artificial material in the world.", "As of 2006, about 7.5 billion cubic meters of concrete are made each year, more than one cubic meter for every person on Earth.=== Reinforced concrete ===Christ the Redeemer'' statue in Rio de Janeiro, Brazil.", "It is made of reinforced concrete clad in a mosaic of thousands of triangular soapstone tiles.The use of reinforcement, in the form of iron was introduced in the 1850s by French industrialist François Coignet, and it was not until the 1880s that German civil engineer G. A. Wayss used steel as reinforcement.", "Concrete is a relatively brittle material that is strong under compression but less in tension.", "Plain, unreinforced concrete is unsuitable for many structures as it is relatively poor at withstanding stresses induced by vibrations, wind loading, and so on.", "Hence, to increase its overall strength, steel rods, wires, mesh or cables can be embedded in concrete before it is set.", "This reinforcement, often known as rebar, resists tensile forces.Reinforced concrete (RC) is a versatile composite and one of the most widely used materials in modern construction.", "It is made up of different constituent materials with very different properties that complement each other.", "In the case of reinforced concrete, the component materials are almost always concrete and steel.", "These two materials form a strong bond together and are able to resist a variety of applied forces, effectively acting as a single structural element.Reinforced concrete can be precast or cast-in-place (in situ) concrete, and is used in a wide range of applications such as; slab, wall, beam, column, foundation, and frame construction.", "Reinforcement is generally placed in areas of the concrete that are likely to be subject to tension, such as the lower portion of beams.", "Usually, there is a minimum of 50 mm cover, both above and below the steel reinforcement, to resist spalling and corrosion which can lead to structural instability.", "Other types of non-steel reinforcement, such as Fibre-reinforced concretes are used for specialized applications, predominately as a means of controlling cracking.=== Precast concrete ===Precast concrete is concrete which is cast in one place for use elsewhere and is a mobile material.", "The largest part of precast production is carried out in the works of specialist suppliers, although in some instances, due to economic and geographical factors, scale of product or difficulty of access, the elements are cast on or adjacent to the construction site.", "Precasting offers considerable advantages because it is carried out in a controlled environment, protected from the elements, but the downside of this is the contribution to greenhouse gas emission from transportation to the construction site.Advantages to be achieved by employing precast concrete:* Preferred dimension schemes exist, with elements of tried and tested designs available from a catalogue.", "* Major savings in time result from manufacture of structural elements apart from the series of events which determine overall duration of the construction, known by planning engineers as the 'critical path'.", "* Availability of Laboratory facilities capable of the required control tests, many being certified for specific testing in accordance with National Standards.", "* Equipment with capability suited to specific types of production such as stressing beds with appropriate capacity, moulds and machinery dedicated to particular products.", "* High-quality finishes achieved direct from the mould eliminate the need for interior decoration and ensure low maintenance costs.===Mass structures===Taum Sauk (Missouri) pumped storage facility in late November 2009.After the original reservoir failed, the new reservoir was made of roller-compacted concrete.Due to cement's exothermic chemical reaction while setting up, large concrete structures such as dams, navigation locks, large mat foundations, and large breakwaters generate excessive heat during hydration and associated expansion.", "To mitigate these effects, ''post-cooling'' is commonly applied during construction.", "An early example at Hoover Dam used a network of pipes between vertical concrete placements to circulate cooling water during the curing process to avoid damaging overheating.", "Similar systems are still used; depending on volume of the pour, the concrete mix used, and ambient air temperature, the cooling process may last for many months after the concrete is placed.", "Various methods also are used to pre-cool the concrete mix in mass concrete structures.Another approach to mass concrete structures that minimizes cement's thermal by-product is the use of roller-compacted concrete, which uses a dry mix which has a much lower cooling requirement than conventional wet placement.", "It is deposited in thick layers as a semi-dry material then roller compacted into a dense, strong mass.===Surface finishes===Black basalt polished concrete floorRaw concrete surfaces tend to be porous and have a relatively uninteresting appearance.", "Many finishes can be applied to improve the appearance and preserve the surface against staining, water penetration, and freezing.Examples of improved appearance include stamped concrete where the wet concrete has a pattern impressed on the surface, to give a paved, cobbled or brick-like effect, and may be accompanied with coloration.", "Another popular effect for flooring and table tops is polished concrete where the concrete is polished optically flat with diamond abrasives and sealed with polymers or other sealants.Other finishes can be achieved with chiseling, or more conventional techniques such as painting or covering it with other materials.The proper treatment of the surface of concrete, and therefore its characteristics, is an important stage in the construction and renovation of architectural structures.===Prestressed structures===Stylized cacti decorate a sound/retaining wall in Scottsdale, ArizonaPrestressed concrete is a form of reinforced concrete that builds in compressive stresses during construction to oppose tensile stresses experienced in use.", "This can greatly reduce the weight of beams or slabs, bybetter distributing the stresses in the structure to make optimal use of the reinforcement.", "For example, a horizontal beam tends to sag.", "Prestressed reinforcement along the bottom of the beam counteracts this.In pre-tensioned concrete, the prestressing is achieved by using steel or polymer tendons or bars that are subjected to a tensile force prior to casting, or for post-tensioned concrete, after casting.There are two different systems being used:* Pretensioned concrete is almost always precast, and contains steel wires (tendons) that are held in tension while the concrete is placed and sets around them.", "* Post-tensioned concrete has ducts through it.", "After the concrete has gained strength, tendons are pulled through the ducts and stressed.", "The ducts are then filled with grout.", "Bridges built in this way have experienced considerable corrosion of the tendons, so external post-tensioning may now be used in which the tendons run along the outer surface of the concrete.More than of highways in the United States are paved with this material.", "Reinforced concrete, prestressed concrete and precast concrete are the most widely used types of concrete functional extensions in modern days.", "For more information see Brutalist architecture.===Placement===Once mixed, concrete is typically transported to the place where it is intended to become a structural item.", "Various methods of transportation and placement are used depending on the distances involve, quantity needed, and other details of application.", "Large amounts are often transported by truck, poured free under gravity or through a tremie, or pumped through a pipe.", "Smaller amounts may be carried in a skip (a metal container which can be tilted or opened to release the contents, usually transported by crane or hoist), or wheelbarrow, or carried in toggle bags for manual placement underwater.====Cold weather placement====''Pohjolatalo'', an office building made of concrete in the city center of Kouvola in Kymenlaakso, FinlandExtreme weather conditions (extreme heat or cold; windy conditions, and humidity variations) can significantly alter the quality of concrete.", "Many precautions are observed in cold weather placement.", "Low temperatures significantly slow the chemical reactions involved in hydration of cement, thus affecting the strength development.", "Preventing freezing is the most important precaution, as formation of ice crystals can cause damage to the crystalline structure of the hydrated cement paste.", "If the surface of the concrete pour is insulated from the outside temperatures, the heat of hydration will prevent freezing.The American Concrete Institute (ACI) definition of cold weather placement, ACI 306, is:* A period when for more than three successive days the average daily air temperature drops below 40 °F (~ 4.5 °C), and* Temperature stays below for more than one-half of any 24-hour period.In Canada, where temperatures tend to be much lower during the cold season, the following criteria are used by CSA A23.1:* When the air temperature is ≤ 5 °C, and* When there is a probability that the temperature may fall below 5 °C within 24 hours of placing the concrete.The minimum strength before exposing concrete to extreme cold is .", "CSA A 23.1 specified a compressive strength of 7.0 MPa to be considered safe for exposure to freezing.==== Underwater placement ====Assembled tremie placing concrete underwaterConcrete may be placed and cured underwater.", "Care must be taken in the placement method to prevent washing out the cement.", "Underwater placement methods include the tremie, pumping, skip placement, manual placement using toggle bags, and bagwork.", "is an alternative method of forming a concrete mass underwater, where the forms are filled with coarse aggregate and the voids then completely filled with pumped grout.===Roads===Concrete roads are more fuel efficient to drive on, more reflective and last significantly longer than other paving surfaces, yet have a much smaller market share than other paving solutions.", "Modern-paving methods and design practices have changed the economics of concrete paving, so that a well-designed and placed concrete pavement will be less expensive on initial costs and significantly less expensive over the life cycle.", "Another major benefit is that pervious concrete can be used, which eliminates the need to place storm drains near the road, and reducing the need for slightly sloped roadway to help rainwater to run off.", "No longer requiring discarding rainwater through use of drains also means that less electricity is needed (more pumping is otherwise needed in the water-distribution system), and no rainwater gets polluted as it no longer mixes with polluted water.", "Rather, it is immediately absorbed by the ground." ], [ "Environment, health and safety", "The manufacture and use of concrete produce a wide range of environmental, economic and social impacts.===Concrete – health and safety===Concrete dust emission from the use of power toolRecycled crushed concrete, to be reused as granular fill, is loaded into a semi-dump truckGrinding of concrete can produce hazardous dust.", "Exposure to cement dust can lead to issues such as silicosis, kidney disease, skin irritation and similar effects.", "The U.S. National Institute for Occupational Safety and Health in the United States recommends attaching local exhaust ventilation shrouds to electric concrete grinders to control the spread of this dust.", "In addition, the Occupational Safety and Health Administration (OSHA) has placed more stringent regulations on companies whose workers regularly come into contact with silica dust.", "An updated silica rule, which OSHA put into effect 23 September 2017 for construction companies, restricted the amount of breathable crystalline silica workers could legally come into contact with to 50 micro grams per cubic meter of air per 8-hour workday.", "That same rule went into effect 23 June 2018 for general industry, hydraulic fracturing and maritime.", "That deadline was extended to 23 June 2021 for engineering controls in the hydraulic fracturing industry.", "Companies which fail to meet the tightened safety regulations can face financial charges and extensive penalties.", "The presence of some substances in concrete, including useful and unwanted additives, can cause health concerns due to toxicity and radioactivity.", "Fresh concrete (before curing is complete) is highly alkaline and must be handled with proper protective equipment.===Concrete, cement and the environment===A major component of concrete is cement, a fine powder used mainly to bind sand and coarser aggregates together in concrete.", "Although a variety of cement types exist, the most common is \"Portland cement\", which is produced by mixing clinker with smaller quantities of other additives such as gypsum and ground limestone.", "The production of clinker, the main constituent of cement, is responsible for the bulk of the sector's greenhouse gas emissions, including both energy intensity and process emissions.The cement industry is one of the three primary producers of carbon dioxide, a major greenhouse gas – the other two being energy production and transportation industries.", "On average, every tonne of cement produced releases one tonne of CO2 into the atmosphere.", "Pioneer cement manufacturers have claimed to reach lower carbon intensities, with 590 kg of CO2eq per tonne of cement produced.", "The emissions are due to combustion and calcination processes, which roughly account for 40% and 60% of the greenhouse gases, respectively.", "Considering that cement is only a fraction of the constituents of concrete, it is estimated that a tonne of concrete is responsible for emitting about 100–200 kg of CO2.Every year more than 10 billion tonnes of concrete are used worldwide.", "In the coming years, large quantities of concrete will continue to be used, and the mitigation of CO2 emissions from the sector will be even more critical.Concrete is used to create hard surfaces that contribute to surface runoff, which can cause heavy soil erosion, water pollution, and flooding, but conversely can be used to divert, dam, and control flooding.", "Concrete dust released by building demolition and natural disasters can be a major source of dangerous air pollution.", "Concrete is a contributor to the urban heat island effect, though less so than asphalt.===Concrete and climate change mitigation===Reducing the cement clinker content might have positive effects on the environmental life-cycle assessment of concrete.", "Some research work on reducing the cement clinker content in concrete has already been carried out.", "However, there exist different research strategies.", "Often replacement of some clinker for large amounts of slag or fly ash was investigated based on conventional concrete technology.", "This could lead to a waste of scarce raw materials such as slag and fly ash.", "The aim of other research activities is the efficient use of cement and reactive materials like slag and fly ash in concrete based on a modified mix design approach.he embodied carbon of a precast concrete facade can be reduced by 50% when using the presented fiber reinforced high performance concrete in place of typical reinforced concrete cladding.Studies have been conducted about commercialization of low-carbon concretes.", "Life cycle assessment (LCA) of low-carbon concrete was investigated according to the ground granulated blast-furnace slag (GGBS) and fly ash (FA) replacement ratios.", "Global warming potential (GWP) of GGBS decreased by 1.1 kg CO2 eq/m3, while FA decreased by 17.3 kg CO2 eq/m3 when the mineral admixture replacement ratio was increased by 10%.", "This study also compared the compressive strength properties of binary blended low-carbon concrete according to the replacement ratios, and the applicable range of mixing proportions was derived.===Concrete and climate change adaptation===High-performance building materials will be particularly important for enhancing resilience, including for flood defenses and critical-infrastructure protection.", "Risks to infrastructure and cities posed by extreme weather events are especially serious for those places exposed to flood and hurricane damage, but also where residents need protection from extreme summer temperatures.", "Traditional concrete can come under strain when exposed to humidity and higher concentrations of atmospheric CO2.While concrete is likely to remain important in applications where the environment is challenging, novel, smarter and more adaptable materials are also needed.=== End-of-life: concrete degradation and waste ===The Tunkhannock Viaduct in northeastern Pennsylvania opened in 1915 and is still in regular use todayConcrete can be damaged by many processes, such as the expansion of corrosion products of the steel reinforcement bars, freezing of trapped water, fire or radiant heat, aggregate expansion, sea water effects, bacterial corrosion, leaching, erosion by fast-flowing water, physical damage and chemical damage (from carbonatation, chlorides, sulfates and distillate water).", "The micro fungi ''Aspergillus alternaria'' and ''Cladosporium'' were able to grow on samples of concrete used as a radioactive waste barrier in the Chernobyl reactor; leaching aluminium, iron, calcium, and silicon.===Recycling of concrete===By far the most common method for recycling dry and hardened concrete involves crushing.", "Mobile sorters and crushers are often installed on construction sites to allow on-site processing.", "In other situations, specific processing sites are established, which are usually able to produce higher quality aggregate.", "Screens are used to achieve desired particle size, and remove dirt, foreign particles and fine material from the coarse aggregate." ], [ "World records", "The world record for the largest concrete pour in a single project is the Three Gorges Dam in Hubei Province, China by the Three Gorges Corporation.", "The amount of concrete used in the construction of the dam is estimated at 16 million cubic meters over 17 years.", "The previous record was 12.3 million cubic meters held by Itaipu hydropower station in Brazil.The world record for concrete pumping was set on 7 August 2009 during the construction of the Parbati Hydroelectric Project, near the village of Suind, Himachal Pradesh, India, when the concrete mix was pumped through a vertical height of .The Polavaram dam works in Andhra Pradesh on 6 January 2019 entered the Guinness World Records by pouring 32,100 cubic metres of concrete in 24 hours.", "The world record for the largest continuously poured concrete raft was achieved in August 2007 in Abu Dhabi by contracting firm Al Habtoor-CCC Joint Venture and the concrete supplier is Unibeton Ready Mix.", "The pour (a part of the foundation for the Abu Dhabi's Landmark Tower) was 16,000 cubic meters of concrete poured within a two-day period.", "The previous record, 13,200 cubic meters poured in 54 hours despite a severe tropical storm requiring the site to be covered with tarpaulins to allow work to continue, was achieved in 1992 by joint Japanese and South Korean consortiums Hazama Corporation and the Samsung C&T Corporation for the construction of the Petronas Towers in Kuala Lumpur, Malaysia.The world record for largest continuously poured concrete floor was completed 8 November 1997, in Louisville, Kentucky by design-build firm EXXCEL Project Management.", "The monolithic placement consisted of of concrete placed in 30 hours, finished to a flatness tolerance of FF 54.60 and a levelness tolerance of FL 43.83.This surpassed the previous record by 50% in total volume and 7.5% in total area.The record for the largest continuously placed underwater concrete pour was completed 18 October 2010, in New Orleans, Louisiana by contractor C. J. Mahan Construction Company, LLC of Grove City, Ohio.", "The placement consisted of 10,251 cubic yards of concrete placed in 58.5 hours using two concrete pumps and two dedicated concrete batch plants.", "Upon curing, this placement allows the cofferdam to be dewatered approximately below sea level to allow the construction of the Inner Harbor Navigation Canal Sill & Monolith Project to be completed in the dry." ], [ "See also", "* * * * * * *" ], [ "Further reading", "*" ], [ "References" ], [ "External links", "* * Advantage and Disadvantage of Concrete* * * Release of ultrafine particles from three simulated building processes* Concrete: The Quest for Greener Alternatives" ] ]

[ [ "Coitus interruptus" ], [ "Introduction", "'''''Coitus interruptus''''', also known as '''withdrawal''', '''pulling out''' or the '''pull-out method''', is a method of birth control during penile-vaginal intercourse, whereby the penis is withdrawn from a vagina prior to ejaculation so that the ejaculate (semen) may be directed away from the vagina in an effort to avoid insemination.", ":Population Action International (1991).", "\"A Guide to Methods of Birth Control.\"", "Briefing Paper No.", "25, Washington, D. C.This method was used by an estimated 38 million couples worldwide in 1991.", "''Coitus interruptus'' does not protect against sexually transmitted infections (STIs)." ], [ "History", "Perhaps the oldest description of the use of the withdrawal method to avoid pregnancy is the story of Onan in the Torah and the Bible.", "This text is believed to have been written down over 2,500 years ago.", "Societies in the ancient civilizations of Greece and Rome preferred small families and are known to have practiced a variety of birth control methods.", "There are references that have led historians to believe withdrawal was sometimes used as birth control.", "However, these societies viewed birth control as a woman's responsibility, and the only well-documented contraception methods were female-controlled devices (both possibly effective, such as pessaries, and ineffective, such as amulets).After the decline of the Roman Empire in the 5th century AD, contraceptive practices fell out of use in Europe; the use of contraceptive pessaries, for example, is not documented again until the 15th century.", "If withdrawal was used during the Roman Empire, knowledge of the practice may have been lost during its decline.From the 18th century until the development of modern methods, withdrawal was one of the most popular methods of birth-control in Europe, North America, and elsewhere." ], [ "Effects", "Like many methods of birth control, reliable effect is not even achieved by correct and consistent use, because the pre-ejaculate can contain sperms.", "Observed failure rates of withdrawal vary depending on the population being studied: American studies have found actual failure rates of 15–28% per year.", "One U.S. study, based on self-reported data from the 2006-2010 cycle of the National Survey of Family Growth, found significant differences in failure rate based on parity status.", "Women with 0 previous births had a 12-month failure rate of only 8.4%, which then increased to 20.4% for those with 1 prior birth and again to 27.7% for those with 2 or more.An analysis of Demographic and Health Surveys in 43 developing countries between 1990 and 2013 found a median 12-month failure rate across subregions of 13.4%, with a range of 7.8-17.1%.", "Individual countries within the subregions were even more varied.", "A large scale study of women in England and Scotland during 1968–1974 to determine the efficacy of various contraceptive methods found a failure rate of 6.7 per 100 woman-years of use.", "This was a “typical use” failure rate, including user failure to use the method correctly.", "In comparison, the combined oral contraceptive pill has an actual use failure rate of 2–8%, - see table ''First-Year Contraceptive Failure Rates'' while intrauterine devices (IUDs) have an actual use failure rate of 0.1–0.8%.", "Condoms have an actual use failure rate of 10–18%.", "However, some authors suggest that actual effectiveness of withdrawal could be similar to the effectiveness of condoms; this area needs further research.", "(See Comparison of birth control methods.", ")For couples that use ''coitus interruptus'' consistently and correctly at every act of intercourse, the failure rate is 4% per year.", "This rate is derived from an educated guess based on a modest chance of sperm in the pre-ejaculate.", "In comparison, the pill has a perfect-use failure rate of 0.3%, IUDs a rate of 0.1-0.6%, and internal condoms a rate of 2%.It has been suggested that the pre-ejaculate (\"Cowper's fluid\") emitted by the penis prior to ejaculation may contain spermatozoa (sperm cells), which would compromise the effectiveness of the method.", "However, several small studies have failed to find any viable sperm in the fluid.", "While no large conclusive studies have been done, it is believed by some that the cause of method (correct-use) failure is the pre-ejaculate fluid picking up sperm from a previous ejaculation.", "For this reason, it is recommended that the male partner urinate between ejaculations, to clear the urethra of sperm, and wash any ejaculate from objects that might come near the woman's vulva (e.g.", "hands and penis).However, recent research suggests that this might not be accurate.", "A contrary, yet non-generalizable study that found mixed evidence, including individual cases of a high sperm concentration, was published in March 2011.A noted limitation to these previous studies' findings is that pre-ejaculate samples were analyzed after the critical two-minute point.", "That is, looking for motile sperm in small amounts of pre-ejaculate via microscope after two minutes – when the sample has most likely dried – makes examination and evaluation \"extremely difficult\".", "Thus, in March 2011 a team of researchers assembled 27 male volunteers and analyzed their pre-ejaculate samples within two minutes after producing them.", "The researchers found that 11 of the 27 men (41%) produced pre-ejaculatory samples that contained sperm, and 10 of these samples (37%) contained a \"fair amount\" of motile sperm (i.e.", "as few as 1 million to as many as 35 million).This study therefore recommends, in order to minimize unintended pregnancy and disease transmission, the use of condoms from the first moment of genital contact.As a point of reference, a study showed that, of couples who conceived within a year of trying, only 2.5% included a male partner with a total sperm count (per ejaculate) of 23 million sperm or less.However, across a wide range of observed values, total sperm count (as with other identified semen and sperm characteristics) has weak power to predict which couples are at risk of pregnancy.", "Regardless, this study introduced the concept that some men may consistently have sperm in their pre-ejaculate, due to a \"leakage,\" while others may not.Similarly, another robust study performed in 2016 found motile sperm in the pre-ejaculate of 16.7% (7/42) healthy men.", "What more, this study attempted to exclude contamination of sperm from ejaculate by drying the pre-ejaculate specimens to reveal a fern-like pattern, characteristics of true pre-ejaculate.", "All pre-ejaculate specimens were examined within an hour of production and then dried; all pre-ejaculate specimens were found to be true pre-ejaculate.It is widely believed that urinating after an ejaculation will flush the urethra of remaining sperm.", "However, some of the subjects in the March 2011 study who produced sperm in their pre-ejaculate did urinate (sometimes more than once) before producing their sample.", "Therefore, some males can release the pre-ejaculate fluid containing sperm without a previous ejaculation." ], [ "Advantages", "The advantage of ''coitus interruptus'' is that it can be used by people who have objections to, or do not have access to, other forms of contraception.", "Some people prefer it so they can avoid possible adverse effects of hormonal contraceptives or so that they can have a full experience and be able to \"feel\" their partner.", "Other reasons for the popularity of this method are it has no direct monetary cost, requires no artificial devices, has no physical side effects, can be practiced without a prescription or medical consultation, and provides no barriers to stimulation." ], [ "Disadvantages", "Compared to the other common reversible methods of contraception such as IUDs, hormonal contraceptives, and male condoms, ''coitus interruptus'' is less effective at preventing pregnancy.", "As a result, it is also less cost-effective than many more effective methods: although the method itself has no direct cost, users have a greater chance of incurring the risks and expenses of either child-birth or abortion.", "Only models that assume all couples practice perfect use of the method find cost savings associated with the choice of withdrawal as a birth control method.The method is largely ineffective in the prevention of sexually transmitted infections (STIs), like HIV, since pre-ejaculate may carry viral particles or bacteria which may infect the partner if this fluid comes in contact with mucous membranes.", "However, a reduction in the volume of bodily fluids exchanged during intercourse may reduce the likelihood of disease transmission compared to using no method due to the smaller number of pathogens present." ], [ "Prevalence", "Based on data from surveys conducted during the late 1990s, 3% of women of childbearing age worldwide rely on withdrawal as their primary method of contraception.", "Regional popularity of the method varies widely, from a low of 1% in Africa to 16% in Western Asia.In the United States, according to the National Survey of Family Growth (NSFG) in 2014, 8.1% of reproductive-aged women reported using withdrawal as a primary contraceptive method.", "This was a significant increase from 2012 when 4.8% of women reported the use of withdrawal as their most effective method.", "However, when withdrawal is used in addition to or in rotation with another contraceptive method, the percentage of women using withdrawal jumps from 5% for sole use and 11% for any withdrawal use in 2002, and for adolescents from 7.1% of sole withdrawal use to 14.6% of any withdrawal use in 2006–2008.When asked if withdrawal was used at least once in the past month by women, use of withdrawal increased from 13% as sole use to 33% ever use in the past month.", "These increases are even more pronounced for adolescents 15 to 19 years old and young women 20 to 24 years old Similarly, the NSFG reports that 9.8% of unmarried men who have had sexual intercourse in the last three months in 2002 used withdrawal, which then increased to 14.5% in 2006–2010, and then to 18.8% in 2011–2015.The use of withdrawal varied by the unmarried man's age and cohabiting status, but not by ethnicity or race.", "The use of withdrawal decreased significantly with increasing age groups, ranging from 26.2% among men aged 15–19 to 12% among men aged 35–44.The use of withdrawal was significantly higher for never-married men (23.0%) compared with formerly married (16.3%) and cohabiting (13.0%) men.For 1998, about 18% of married men in Turkey reported using withdrawal as a contraceptive method." ], [ "See also", "* ''Coitus reservatus'' * ''Coitus saxonicus'' * Masturbation" ], [ "References" ], [ "External links", "* Contraception and abortion in Islam* Withdrawal" ] ]

[ [ "Condom" ], [ "Introduction", "A '''condom''' is a sheath-shaped barrier device used during sexual intercourse to reduce the probability of pregnancy or a sexually transmitted infection (STI).", "There are both male and female condoms.The male condom is rolled onto an erect penis before intercourse and works by forming a physical barrier which blocks semen from entering the body of a sexual partner.", "Male condoms are typically made from latex and, less commonly, from polyurethane, polyisoprene, or lamb intestine.", "Male condoms have the advantages of ease of use, ease of access, and few side effects.", "Individuals with latex allergy should use condoms made from a material other than latex, such as polyurethane.", "Female condoms are typically made from polyurethane and may be used multiple times.With proper use—and use at every act of intercourse—women whose partners use male condoms experience a 2% per-year pregnancy rate.", "With typical use, the rate of pregnancy is 18% per-year.", "Their use greatly decreases the risk of gonorrhea, chlamydia, trichomoniasis, hepatitis B, and HIV/AIDS.", "To a lesser extent, they also protect against genital herpes, human papillomavirus (HPV), and syphilis.Condoms as a method of preventing STIs have been used since at least 1564.Rubber condoms became available in 1855, followed by latex condoms in the 1920s.", "It is on the World Health Organization's List of Essential Medicines.", "As of 2019, globally around 21% of those using birth control use the condom, making it the second-most common method after female sterilization (24%).", "Rates of condom use are highest in East and Southeast Asia, Europe and North America.", "About six to nine billion are sold a year." ], [ "Medical uses", "=== Birth control ===The effectiveness of condoms, as of most forms of contraception, can be assessed two ways.", "''Perfect use'' or ''method'' effectiveness rates only include people who use condoms properly and consistently.", "''Actual use'', or ''typical use'' effectiveness rates are of all condom users, including those who use condoms incorrectly or do not use condoms at every act of intercourse.", "Rates are generally presented for the first year of use.", "Most commonly the Pearl Index is used to calculate effectiveness rates, but some studies use decrement tables.The typical use pregnancy rate among condom users varies depending on the population being studied, ranging from 10 to 18% per year.", "The perfect use pregnancy rate of condoms is 2% per year.", "Condoms may be combined with other forms of contraception (such as spermicide) for greater protection.=== Sexually transmitted infections ===A giant replica of a condom on the Obelisk of Buenos Aires, Argentina, part of an awareness campaign for the 2005 World AIDS DayCondoms are widely recommended for the prevention of sexually transmitted infections (STIs).", "They have been shown to be effective in reducing infection rates in both men and women.", "While not perfect, the condom is effective at reducing the transmission of organisms that cause AIDS, genital herpes, cervical cancer, genital warts, syphilis, chlamydia, gonorrhea, and other diseases.", "Condoms are often recommended as an adjunct to more effective birth control methods (such as IUD) in situations where STI protection is also desired.For this reason, condoms are frequently used by those in the swinging (sexual practice) community.According to a 2000 report by the National Institutes of Health (NIH), consistent use of latex condoms reduces the risk of HIV transmission by approximately 85% relative to risk when unprotected, putting the seroconversion rate (infection rate) at 0.9 per 100 person-years with condom, down from 6.7 per 100 person-years.", "Analysis published in 2007 from the University of Texas Medical Branch and the World Health Organization found similar risk reductions of 80–95%.The 2000 NIH review concluded that condom use significantly reduces the risk of gonorrhea for men.", "A 2006 study reports that proper condom use decreases the risk of transmission of human papillomavirus (HPV) to women by approximately 70%.", "Another study in the same year found consistent condom use was effective at reducing transmission of herpes simplex virus-2, also known as genital herpes, in both men and women.Although a condom is effective in limiting exposure, some disease transmission may occur even with a condom.", "Infectious areas of the genitals, especially when symptoms are present, may not be covered by a condom, and as a result, some diseases like HPV and herpes may be transmitted by direct contact.", "The primary effectiveness issue with using condoms to prevent STIs, however, is inconsistent use.Condoms may also be useful in treating potentially precancerous cervical changes.", "Exposure to human papillomavirus, even in individuals already infected with the virus, appears to increase the risk of precancerous changes.", "The use of condoms helps promote regression of these changes.", "In addition, researchers in the UK suggest that a hormone in semen can aggravate existing cervical cancer, condom use during sex can prevent exposure to the hormone.=== Causes of failure ===Condom fitting in size over a penis made of siliconeCondoms may slip off the penis after ejaculation, break due to improper application or physical damage (such as tears caused when opening the package), or break or slip due to latex degradation (typically from usage past the expiration date, improper storage, or exposure to oils).", "The rate of breakage is between 0.4% and 2.3%, while the rate of slippage is between 0.6% and 1.3%.", "Even if no breakage or slippage is observed, 1–3% of women will test positive for semen residue after intercourse with a condom.", "Failure rates are higher for anal sex, and until 2022, condoms were only approved by the FDA for vaginal sex.", "The One Male Condom received FDA approval for anal sex on 23 February 2022.", "\"Double bagging\", using two condoms at once, is often believed to cause a higher rate of failure due to the friction of rubber on rubber.", "This claim is not supported by research.", "The limited studies that have been done found that the simultaneous use of multiple condoms decreases the risk of condom breakage.Different modes of condom failure result in different levels of semen exposure.", "If a failure occurs during application, the damaged condom may be disposed of and a new condom applied before intercourse begins – such failures generally pose no risk to the user.", "One study found that semen exposure from a broken condom was about half that of unprotected intercourse; semen exposure from a slipped condom was about one-fifth that of unprotected intercourse.Standard condoms will fit almost any penis, with varying degrees of comfort or risk of slippage.", "Many condom manufacturers offer \"snug\" or \"magnum\" sizes.", "Some manufacturers also offer custom sized-to-fit condoms, with claims that they are more reliable and offer improved sensation/comfort.", "Some studies have associated larger penises and smaller condoms with increased breakage and decreased slippage rates (and vice versa), but other studies have been inconclusive.It is recommended for condoms manufacturers to avoid very thick or very thin condoms, because they are both considered less effective.", "Some authors encourage users to choose thinner condoms \"for greater durability, sensation, and comfort\", but others warn that \"the thinner the condom, the smaller the force required to break it\".Experienced condom users are significantly less likely to have a condom slip or break compared to first-time users, although users who experience one slippage or breakage are more likely to suffer a second such failure.", "An article in ''Population Reports'' suggests that education on condom use reduces behaviors that increase the risk of breakage and slippage.", "A Family Health International publication also offers the view that education can reduce the risk of breakage and slippage, but emphasizes that more research needs to be done to determine all of the causes of breakage and slippage.Among people who intend condoms to be their form of birth control, pregnancy may occur when the user has sex without a condom.", "The person may have run out of condoms, or be traveling and not have a condom with them, or dislike the feel of condoms and decide to \"take a chance\".", "This behavior is the primary cause of typical use failure (as opposed to method or perfect use failure).Another possible cause of condom failure is sabotage.", "One motive is to have a child against a partner's wishes or consent.", "Some commercial sex workers from Nigeria reported clients sabotaging condoms in retaliation for being coerced into condom use.", "Using a fine needle to make several pinholes at the tip of the condom is believed to significantly impact on their effectiveness.", "Cases of such condom sabotage have occurred." ], [ "Side effects", "The use of latex condoms by people with an allergy to latex can cause allergic symptoms, such as skin irritation.", "In people with severe latex allergies, using a latex condom can potentially be life-threatening.", "Repeated use of latex condoms can also cause the development of a latex allergy in some people.", "Irritation may also occur due to spermicides that may be present." ], [ "Use", "Illustrations showing how to put on a condomMale condoms are usually packaged inside a foil or plastic wrapper, in a rolled-up form, and are designed to be applied to the tip of the penis and then unrolled over the erect penis.", "It is important that some space be left in the tip of the condom so that semen has a place to collect; otherwise it may be forced out of the base of the device.", "Most condoms have a teat end for this purpose.", "After use, it is recommended the condom be wrapped in tissue or tied in a knot, then disposed of in a trash receptacle.", "Condoms are used to reduce the likelihood of pregnancy during intercourse and to reduce the likelihood of contracting sexually transmitted infections (STIs).", "Condoms are also used during fellatio to reduce the likelihood of contracting STIs.Some couples find that putting on a condom interrupts sex, although others incorporate condom application as part of their foreplay.", "Some men and women find the physical barrier of a condom dulls sensation.", "Advantages of dulled sensation can include prolonged erection and delayed ejaculation; disadvantages might include a loss of some sexual excitement.", "Advocates of condom use also cite their advantages of being inexpensive, easy to use, and having few side effects.=== Adult film industry ===In 2012 proponents gathered 372,000 voter signatures through a citizens' initiative in Los Angeles County to put Measure B on the 2012 ballot.", "As a result, Measure B, a law requiring the use of condoms in the production of pornographic films, was passed.", "This requirement has received much criticism and is said by some to be counter-productive, merely forcing companies that make pornographic films to relocate to other places without this requirement.", "Producers claim that condom use depresses sales.=== Sex education ===Condoms are often used in sex education programs, because they have the capability to reduce the chances of pregnancy and the spread of some sexually transmitted infections when used correctly.", "A recent American Psychological Association (APA) press release supported the inclusion of information about condoms in sex education, saying \"comprehensive sexuality education programs ... discuss the appropriate use of condoms\", and \"promote condom use for those who are sexually active.", "\"In the United States, teaching about condoms in public schools is opposed by some religious organizations.", "Planned Parenthood, which advocates family planning and sex education, argues that no studies have shown abstinence-only programs to result in delayed intercourse, and cites surveys showing that 76% of American parents want their children to receive comprehensive sexuality education including condom use.=== Infertility treatment ===Common procedures in infertility treatment such as semen analysis and intrauterine insemination (IUI) require collection of semen samples.", "These are most commonly obtained through masturbation, but an alternative to masturbation is use of a special ''collection condom'' to collect semen during sexual intercourse.Collection condoms are made from silicone or polyurethane, as latex is somewhat harmful to sperm.", "Some religions prohibit masturbation entirely.", "Also, compared with samples obtained from masturbation, semen samples from collection condoms have higher total sperm counts, sperm motility, and percentage of sperm with normal morphology.", "For this reason, they are believed to give more accurate results when used for semen analysis, and to improve the chances of pregnancy when used in procedures such as intracervical or intrauterine insemination.", "Adherents of religions that prohibit contraception, such as Catholicism, may use collection condoms with holes pricked in them.For fertility treatments, a collection condom may be used to collect semen during sexual intercourse where the semen is provided by the woman's partner.", "Private sperm donors may also use a collection condom to obtain samples through masturbation or by sexual intercourse with a partner and will transfer the ejaculate from the collection condom to a specially designed container.", "The sperm is transported in such containers, in the case of a donor, to a recipient woman to be used for insemination, and in the case of a woman's partner, to a fertility clinic for processing and use.", "However, transportation may reduce the fecundity of the sperm.", "Collection condoms may also be used where semen is produced at a sperm bank or fertility clinic.", "''Condom therapy'' is sometimes prescribed to infertile couples when the female has high levels of antisperm antibodies.", "The theory is that preventing exposure to her partner's semen will lower her level of antisperm antibodies, and thus increase her chances of pregnancy when condom therapy is discontinued.", "However, condom therapy has not been shown to increase subsequent pregnancy rates.=== Other uses ===Condoms excel as multipurpose containers and barriers because they are waterproof, elastic, durable, and (for military and espionage uses) will not arouse suspicion if found.Ongoing military utilization began during World War II, and includes covering the muzzles of rifle barrels to prevent fouling, the waterproofing of firing assemblies in underwater demolitions, and storage of corrosive materials and garrotes by paramilitary agencies.Condoms have also been used to smuggle alcohol, cocaine, heroin, and other drugs across borders and into prisons by filling the condom with drugs, tying it in a knot and then either swallowing it or inserting it into the rectum.", "These methods are very dangerous and potentially lethal; if the condom breaks, the drugs inside become absorbed into the bloodstream and can cause an overdose.Medically, condoms can be used to cover endovaginal ultrasound probes, or in field chest needle decompressions they can be used to make a one-way valve.Condoms have also been used to protect scientific samples from the environment, and to waterproof microphones for underwater recording." ], [ "Types", "Most condoms have a reservoir tip or teat end, making it easier to accommodate the man's ejaculate.", "Condoms come in different sizes and shapes.They also come in a variety of surfaces intended to stimulate the user's partner.", "Condoms are usually supplied with a lubricant coating to facilitate penetration, while flavored condoms are principally used for oral sex.", "As mentioned above, most condoms are made of latex, but polyurethane and lambskin condoms also exist.=== Female condom ===A female condomMale condoms have a tight ring to form a seal around the penis, while female condoms usually have a large stiff ring to prevent them from slipping into the body orifice.", "The Female Health Company produced a female condom that was initially made of polyurethane, but newer versions are made of nitrile rubber.", "Medtech Products produces a female condom made of latex.=== Materials ======= Natural latex ====An unrolled latex condomLatex has outstanding elastic properties: Its tensile strength exceeds 30 MPa, and latex condoms may be stretched in excess of 800% before breaking.", "In 1990 the ISO set standards for condom production (ISO 4074, Natural latex rubber condoms), and the EU followed suit with its CEN standard (Directive 93/42/EEC concerning medical devices).", "Every latex condom is tested for holes with an electric current.", "If the condom passes, it is rolled and packaged.", "In addition, a portion of each batch of condoms is subject to water leak and air burst testing.While the advantages of latex have made it the most popular condom material, it does have some drawbacks.", "Latex condoms are damaged when used with oil-based substances as lubricants, such as petroleum jelly, cooking oil, baby oil, mineral oil, skin lotions, suntan lotions, cold creams, butter or margarine.", "Contact with oil makes latex condoms more likely to break or slip off due to loss of elasticity caused by the oils.", "Additionally, latex allergy precludes use of latex condoms and is one of the principal reasons for the use of other materials.", "In May 2009, the U.S. Food and Drug Administration (FDA) granted approval for the production of condoms composed of Vytex, latex that has been treated to remove 90% of the proteins responsible for allergic reactions.", "An allergen-free condom made of synthetic latex (polyisoprene) is also available.==== Synthetic ====The most common non-latex condoms are made from polyurethane.", "Condoms may also be made from other synthetic materials, such as AT-10 resin, and most polyisoprene.Polyurethane condoms tend to be the same width and thickness as latex condoms, with most polyurethane condoms between 0.04 mm and 0.07 mm thick.Polyurethane can be considered better than latex in several ways: it conducts heat better than latex, is not as sensitive to temperature and ultraviolet light (and so has less rigid storage requirements and a longer shelf life), can be used with oil-based lubricants, is less allergenic than latex, and does not have an odor.", "Polyurethane condoms have gained FDA approval for sale in the United States as an effective method of contraception and HIV prevention, and under laboratory conditions have been shown to be just as effective as latex for these purposes.However, polyurethane condoms are less elastic than latex ones, and may be more likely to slip or break than latex, lose their shape or bunch up more than latex, and are more expensive.Polyisoprene is a synthetic version of natural rubber latex.", "While significantly more expensive, it has the advantages of latex (such as being softer and more elastic than polyurethane condoms) without the protein which is responsible for latex allergies.", "Unlike polyurethane condoms, they cannot be used with an oil-based lubricant.==== Lambskin ====Condoms made from sheep intestines, labeled \"lambskin\", are also available.", "Although they are generally effective as a contraceptive by blocking sperm, studies have found that they are less effective than latex in preventing the transmission of sexually transmitted infections because of pores in the material.", "This is because intestines, by their nature, are porous, permeable membranes, and while sperm are too large to pass through the pores, viruses—such as HIV, herpes, and genital warts—are small enough to pass.As a result of laboratory data on condom porosity, in 1989, the FDA began requiring lambskin condom manufacturers to indicate that the products were not to be used for the prevention of sexually transmitted infections.", "The FDA cautions that while lambskin condoms \"provide good birth control and a varying degree of protection against some, but not all, sexually transmitted diseases\", people do not know what STIs a partner might have, and thus cannot assume that a lambskin condom will protect them.While lambskin condoms avoid triggering latex allergies, polyurethane condoms do as well, while also protecting more reliably against STIs.", "Lambskin condoms' can be as much as quadruple latex condoms'.", "As slaughter by-products, lambskin condoms are also not vegetarian.", "Pharmacist advice prepared by the ''Canadian Pharmaceutical Journal'' says that lambskin condoms \"are generally not recommended\" due to limited STI prevention.", "An article in ''Adolescent Medicine'' advises that they \"should be used only for pregnancy prevention\".=== Spermicide ===Some latex condoms are lubricated at the manufacturer with a small amount of a nonoxynol-9, a spermicidal chemical.", "According to ''Consumer Reports'', condoms lubricated with spermicide have no additional benefit in preventing pregnancy, have a shorter shelf life, and may cause urinary tract infections in women.", "In contrast, application of separately packaged spermicide ''is'' believed to increase the contraceptive efficacy of condoms.Nonoxynol-9 was once believed to offer additional protection against STIs (including HIV) but recent studies have shown that, with frequent use, nonoxynol-9 may increase the risk of HIV transmission.", "The World Health Organization says that spermicidally lubricated condoms should no longer be promoted.", "However, it recommends using a nonoxynol-9 lubricated condom over no condom at all.", ", nine condom manufacturers have stopped manufacturing condoms with nonoxynol-9 and Planned Parenthood has discontinued the distribution of condoms so lubricated.=== Ribbed and studded ===A ribbed condomTextured condoms include studded and ribbed condoms which can provide extra sensations to both partners.", "The studs or ribs can be located on the inside, outside, or both; alternatively, they are located in specific sections to provide directed stimulation to either the G-spot or frenulum.", "Many textured condoms which advertise \"mutual pleasure\" also are bulb-shaped at the top, to provide extra stimulation to the penis.", "Some women experience irritation during vaginal intercourse with studded condoms.=== Other ===The anti-rape condom is another variation designed to be worn by women.", "It is designed to cause pain to the attacker, hopefully allowing the victim a chance to escape.A collection condom is used to collect semen for fertility treatments or sperm analysis.", "These condoms are designed to maximize sperm life.Some condom-like devices are intended for entertainment only, such as glow-in-the dark condoms.", "These novelty condoms may not provide protection against pregnancy and STIs.In February 2022, the U.S. Food and Drug Administration (FDA) approved the first condoms specifically indicated to help reduce transmission of sexually transmitted infections (STIs) during anal intercourse." ], [ "Prevalence", "The prevalence of condom use varies greatly between countries.", "Most surveys of contraceptive use are among married women, or women in informal unions.", "Japan has the highest rate of condom usage in the world: in that country, condoms account for almost 80% of contraceptive use by married women.", "On average, in developed countries, condoms are the most popular method of birth control: 28% of married contraceptive users rely on condoms.", "In the average less-developed country, condoms are less common: only 6–8% of married contraceptive users choose condoms." ], [ "History", "A page from ''De Morbo Gallico'' ('On the French Disease'), Gabriele Falloppio's treatise on syphilis.", "Published in 1564, it describes what is possibly the first use of condoms.=== Before the 19th century ===Whether condoms were used in ancient civilizations is debated by archaeologists and historians.", "In ancient Egypt, Greece, and Rome, pregnancy prevention was generally seen as a woman's responsibility, and the only well documented contraception methods were female-controlled devices.", "In Asia before the 15th century, some use of glans condoms (devices covering only the head of the penis) is recorded.", "Condoms seem to have been used for contraception, and to have been known only by members of the upper classes.", "In China, glans condoms may have been made of oiled silk paper, or of lamb intestines.", "In Japan, condoms called ''Kabuto-gata'' (甲形) were made of tortoise shell or animal horn.Japanese Shunga Ukiyoe from the 19th century depicting Kabuto-gata among its sex toys used among women, stored by the British Museum|thumb|upright=1.2In 16th-century Italy, anatomist and physician Gabriele Falloppio wrote a treatise on syphilis.", "The earliest documented strain of syphilis, first appearing in Europe in a 1490s outbreak, caused severe symptoms and often death within a few months of contracting the disease.", "Falloppio's treatise is the earliest uncontested description of condom use: it describes linen sheaths soaked in a chemical solution and allowed to dry before use.", "The cloths he described were sized to cover the glans of the penis, and were held on with a ribbon.", "Falloppio claimed that an experimental trial of the linen sheath demonstrated protection against syphilis.After this, the use of penis coverings to protect from disease is described in a wide variety of literature throughout Europe.", "The first indication that these devices were used for birth control, rather than disease prevention, is the 1605 theological publication ''De iustitia et iure'' (On justice and law) by Catholic theologian Leonardus Lessius, who condemned them as immoral.", "In 1666, the English Birth Rate Commission attributed a recent downward fertility rate to use of \"condons\", the first documented use of that word or any similar spelling.", "Other early spellings include \"condam\" and \"quondam\", from which the Italian derivation ''guantone'' has been suggested, from ''guanto'', \"a glove\".A condom made from animal intestine circa 1900In addition to linen, condoms during the Renaissance were made out of intestines and bladder.", "In the late 16th century, Dutch traders introduced condoms made from \"fine leather\" to Japan.", "Unlike the horn condoms used previously, these leather condoms covered the entire penis.Giacomo Casanova tests his condom for holes by inflating itCasanova in the 18th century was one of the first reported using \"assurance caps\" to prevent impregnating his mistresses.From at least the 18th century, condom use was opposed in some legal, religious, and medical circles for essentially the same reasons that are given today: condoms reduce the likelihood of pregnancy, which some thought immoral or undesirable for the nation; they do not provide full protection against sexually transmitted infections, while belief in their protective powers was thought to encourage sexual promiscuity; and, they are not used consistently due to inconvenience, expense, or loss of sensation.Despite some opposition, the condom market grew rapidly.", "In the 18th century, condoms were available in a variety of qualities and sizes, made from either linen treated with chemicals, or \"skin\" (bladder or intestine softened by treatment with sulfur and lye).", "They were sold at pubs, barbershops, chemist shops, open-air markets, and at the theater throughout Europe and Russia.", "They later spread to America, although in every place there were generally used only by the middle and upper classes, due to both expense and lack of sex education.=== 1800 through 1920s ===An old-fashioned condom packageThe early 19th century saw contraceptives promoted to the poorer classes for the first time.", "Writers on contraception tended to prefer other birth control methods to the condom.", "By the late 19th century, many feminists expressed distrust of the condom as a contraceptive, as its use was controlled and decided upon by men alone.", "They advocated instead for methods controlled by women, such as diaphragms and spermicidal douches.", "Other writers cited both the expense of condoms and their unreliability (they were often riddled with holes and often fell off or tore).", "Still, they discussed condoms as a good option for some and the only contraceptive that protects from disease.Many countries passed laws impeding the manufacture and promotion of contraceptives.", "In spite of these restrictions, condoms were promoted by traveling lecturers and in newspaper advertisements, using euphemisms in places where such ads were illegal.", "Instructions on how to make condoms at home were distributed in the United States and Europe.", "Despite social and legal opposition, at the end of the 19th century the condom was the Western world's most popular birth control method.During World War I, the U.S. military was the only one that did not promote condom use.", "Posters such as these were intended to promote abstinence.Beginning in the second half of the 19th century, American rates of sexually transmitted infections skyrocketed.", "Causes cited by historians include the effects of the American Civil War and the ignorance of prevention methods promoted by the Comstock laws.", "To fight the growing epidemic, sex education classes were introduced to public schools for the first time, teaching about venereal diseases and how they were transmitted.", "They generally taught abstinence was the only way to avoid sexually transmitted infections.", "Condoms were not promoted for disease prevention because the medical community and moral watchdogs considered STIs to be punishment for sexual misbehavior.", "The stigma against people with these diseases was so significant that many hospitals refused to treat people with syphilis.Condom (and manual) from 1813The German military was the first to promote condom use among its soldiers in the later 19th century.", "Early 20th century experiments by the American military concluded that providing condoms to soldiers significantly lowered rates of sexually transmitted infections.", "During World War I, the United States and (at the beginning of the war only) Britain were the only countries with soldiers in Europe who did not provide condoms and promote their use.In the decades after World War I, there remained social and legal obstacles to condom use throughout the U.S. and Europe.", "Founder of psychoanalysis Sigmund Freud opposed all methods of birth control because their failure rates were too high.", "Freud was especially opposed to the condom because he thought it cut down on sexual pleasure.", "Some feminists continued to oppose male-controlled contraceptives such as condoms.", "In 1920 the Church of England's Lambeth Conference condemned all \"unnatural means of conception avoidance\".", "The Bishop of London, Arthur Winnington-Ingram, complained of the huge number of condoms discarded in alleyways and parks, especially after weekends and holidays.However, European militaries continued to provide condoms to their members for disease protection, even in countries where they were illegal for the general population.", "Through the 1920s, catchy names and slick packaging became an increasingly important marketing technique for many consumer items, including condoms and cigarettes.", "Quality testing became more common, involving filling each condom with air followed by one of several methods intended to detect loss of pressure.", "Worldwide, condom sales doubled in the 1920s.=== Rubber and manufacturing advances ===In 1839, Charles Goodyear discovered a way of processing natural rubber, which is too stiff when cold and too soft when warm, in such a way as to make it elastic.", "This proved to have advantages for the manufacture of condoms; unlike the sheep's gut condoms, they could stretch and did not tear quickly when used.", "The rubber vulcanization process was patented by Goodyear in 1844.The first rubber condom was produced in 1855.The earliest rubber condoms had a seam and were as thick as a bicycle inner tube.", "Besides this type, small rubber condoms covering only the glans were often used in England and the United States.", "There was more risk of losing them and if the rubber ring was too tight, it would constrict the penis.", "This type of condom was the original \"capote\" (French for condom), perhaps because of its resemblance to a woman's bonnet worn at that time, also called a capote.For many decades, rubber condoms were manufactured by wrapping strips of raw rubber around penis-shaped molds, then dipping the wrapped molds in a chemical solution to cure the rubber.", "In 1912, Polish-born inventor Julius Fromm developed a new, improved manufacturing technique for condoms: dipping glass molds into a raw rubber solution.", "Called ''cement dipping'', this method required adding gasoline or benzene to the rubber to make it liquid.Around 1920 patent lawyer and vice-president of the United States Rubber Company Ernest Hopkinson invented a new technique of converting latex into rubber without a coagulant (demulsifier), which featured using water as a solvent and warm air to dry the solution, as well as optionally preserving liquid latex with ammonia.", "Condoms made this way, commonly called \"latex\" ones, required less labor to produce than cement-dipped rubber condoms, which had to be smoothed by rubbing and trimming.", "The use of water to suspend the rubber instead of gasoline and benzene eliminated the fire hazard previously associated with all condom factories.", "Latex condoms also performed better for the consumer: they were stronger and thinner than rubber condoms, and had a shelf life of five years (compared to three months for rubber).Until the twenties, all condoms were individually hand-dipped by semi-skilled workers.", "Throughout the decade of the 1920s, advances in the automation of the condom assembly line were made.", "The first fully automated line was patented in 1930.Major condom manufacturers bought or leased conveyor systems, and small manufacturers were driven out of business.", "The skin condom, now significantly more expensive than the latex variety, became restricted to a niche high-end market.=== 1930 to present ===Condom tin, \"3 Merry Widows\" brand, circa 1930.A packet of \"Anti-baby\" condoms from Germany.", "c1980s.In 1930 the Anglican Church's Lambeth Conference sanctioned the use of birth control by married couples.", "In 1931 the Federal Council of Churches in the U.S. issued a similar statement.", "The Roman Catholic Church responded by issuing the encyclical ''Casti connubii'' affirming its opposition to all contraceptives, a stance it has never reversed.", "In the 1930s, legal restrictions on condoms began to be relaxed.", "But during this period Fascist Italy and Nazi Germany increased restrictions on condoms (limited sales as disease preventatives were still allowed).", "During the Depression, condom lines by Schmid gained in popularity.", "Schmid still used the cement-dipping method of manufacture which had two advantages over the latex variety.", "Firstly, cement-dipped condoms could be safely used with oil-based lubricants.", "Secondly, while less comfortable, these older-style rubber condoms could be reused and so were more economical, a valued feature in hard times.", "More attention was brought to quality issues in the 1930s, and the U.S. Food and Drug Administration began to regulate the quality of condoms sold in the United States.Throughout World War II, condoms were not only distributed to male U.S. military members, but also heavily promoted with films, posters, and lectures.", "European and Asian militaries on both sides of the conflict also provided condoms to their troops throughout the war, even Germany which outlawed all civilian use of condoms in 1941.In part because condoms were readily available, soldiers found a number of non-sexual uses for the devices, many of which continue to this day.", "After the war, condom sales continued to grow.", "From 1955 to 1965, 42% of Americans of reproductive age relied on condoms for birth control.", "In Britain from 1950 to 1960, 60% of married couples used condoms.", "The birth control pill became the world's most popular method of birth control in the years after its 1960 début, but condoms remained a strong second.", "The U.S. Agency for International Development pushed condom use in developing countries to help solve the \"world population crises\": by 1970 hundreds of millions of condoms were being used each year in India alone.", "(This number has grown in recent decades: in 2004, the government of India purchased 1.9 billion condoms for distribution at family planning clinics.", ")A condom given out by NYC Health Department during the Stonewall 50 – WorldPride NYC 2019 celebrations.In the 1960s and 1970s quality regulations tightened, and more legal barriers to condom use were removed.", "In Ireland, legal condom sales were allowed for the first time in 1978.Advertising, however was one area that continued to have legal restrictions.", "In the late 1950s, the American National Association of Broadcasters banned condom advertisements from national television; this policy remained in place until 1979.After it was discovered in the early 1980s that AIDS can be a sexually transmitted infection, the use of condoms was encouraged to prevent transmission of HIV.", "Despite opposition by some political, religious, and other figures, national condom promotion campaigns occurred in the U.S. and Europe.", "These campaigns increased condom use significantly.Due to increased demand and greater social acceptance, condoms began to be sold in a wider variety of retail outlets, including in supermarkets and in discount department stores such as Walmart.", "Condom sales increased every year until 1994, when media attention to the AIDS pandemic began to decline.", "The phenomenon of decreasing use of condoms as disease preventatives has been called ''prevention fatigue'' or ''condom fatigue''.", "Observers have cited condom fatigue in both Europe and North America.", "As one response, manufacturers have changed the tone of their advertisements from scary to humorous.New developments continued to occur in the condom market, with the first polyurethane condom—branded Avanti and produced by the manufacturer of Durex—introduced in the 1990s.", "Worldwide condom use is expected to continue to grow: one study predicted that developing nations would need 18.6 billion condoms by 2015., condoms are available inside prisons in Canada, most of the European Union, Australia, Brazil, Indonesia, South Africa, and the US states of Vermont (on 17 September 2013, the Californian Senate approved a bill for condom distribution inside the state's prisons, but the bill was not yet law at the time of approval).The global condom market was estimated at US$9.2 billion in 2020.=== Etymology and other terms ===The term ''condom'' first appears in the early 18th century: early forms include ''condum'' (1706 and 1717), ''condon'' (1708) and ''cundum'' (1744).", "The word's etymology is unknown.", "In popular tradition, the invention and naming of the condom came to be attributed to an associate of England's King Charles II, one \"Dr.", "Condom\" or \"Earl of Condom\".", "There is however no evidence of the existence of such a person, and condoms had been used for over one hundred years before King Charles II acceded to the throne in 1660.A variety of unproven Latin etymologies have been proposed, including (receptacle), (house), and (scabbard or case).", "It has also been speculated to be from the Italian word ''guantone'', derived from ''guanto'', meaning glove.", "William E. Kruck wrote an article in 1981 concluding that, \"As for the word 'condom', I need state only that its origin remains completely unknown, and there ends this search for an etymology.\"", "Modern dictionaries may also list the etymology as \"unknown\".Other terms are also commonly used to describe condoms.", "In North America condoms are also commonly known as ''prophylactics'', or ''rubbers''.", "In Britain they may be called ''French letters'' or ''rubber johnnies''.", "Additionally, condoms may be referred to using the manufacturer's name." ], [ "Society and culture", "Some moral and scientific criticism of condoms exists despite the many benefits of condoms agreed on by scientific consensus and sexual health experts.Condom usage is typically recommended for new couples who have yet to develop full trust in their partner with regard to STIs.", "Established couples on the other hand have few concerns about STIs, and can use other methods of birth control such as the pill, which does not act as a barrier to intimate sexual contact.", "Note that the polar debate with regard to condom usage is attenuated by the target group the argument is directed.", "Notably the age category and stable partner question are factors, as well as the distinction between heterosexual and homosexuals, who have different kinds of sex and have different risk consequences and factors.Among the prime objections to condom usage is the blocking of erotic sensation, or the intimacy that barrier-free sex provides.", "As the condom is held tightly to the skin of the penis, it diminishes the delivery of stimulation through rubbing and friction.", "Condom proponents claim this has the benefit of making sex last longer, by diminishing sensation and delaying male ejaculation.", "Those who promote condom-free heterosexual sex (slang: \"bareback\") claim that the condom puts a barrier between partners, diminishing what is normally a highly sensual, intimate, and spiritual connection between partners.=== Religious ===The United Church of Christ (UCC), a Reformed denomination of the Congregationalist tradition, promotes the distribution of condoms in churches and faith-based educational settings.", "Michael Shuenemeyer, a UCC minister, has stated that \"The practice of safer sex is a matter of life and death.", "People of faith make condoms available because we have chosen life so that we and our children may live.", "\"On the other hand, the Roman Catholic Church opposes all kinds of sexual acts outside of marriage, as well as any sexual act in which the chance of successful conception has been reduced by direct and intentional acts (for example, surgery to prevent conception) or foreign objects (for example, condoms).The use of condoms to prevent STI transmission is not specifically addressed by Catholic doctrine, and is currently a topic of debate among theologians and high-ranking Catholic authorities.", "A few, such as Belgian Cardinal Godfried Danneels, believe the Catholic Church should actively support condoms used to prevent disease, especially serious diseases such as AIDS.", "However, the majority view—including all statements from the Vatican—is that condom-promotion programs encourage promiscuity, thereby actually increasing STI transmission.", "This view was most recently reiterated in 2009 by Pope Benedict XVI.The Roman Catholic Church is the largest organized body of any world religion.", "The church has hundreds of programs dedicated to fighting the AIDS epidemic in Africa, but its opposition to condom use in these programs has been highly controversial.In a November 2011 interview, Pope Benedict XVI discussed for the first time the use of condoms to prevent STI transmission.", "He said that the use of a condom can be justified in a few individual cases if the purpose is to reduce the risk of an HIV infection.", "He gave as an example male prostitutes.", "There was some confusion at first whether the statement applied only to homosexual prostitutes and thus not to heterosexual intercourse at all.", "However, Federico Lombardi, spokesman for the Vatican, clarified that it applied to heterosexual and transsexual prostitutes, whether male or female, as well.", "He did, however, also clarify that the Vatican's principles on sexuality and contraception had not been changed.=== Scientific and environmental ===More generally, some scientific researchers have expressed objective concern over certain ingredients sometimes added to condoms, notably talc and nitrosamines.", "Dry dusting powders are applied to latex condoms before packaging to prevent the condom from sticking to itself when rolled up.", "Previously, talc was used by most manufacturers, but cornstarch is currently the most popular dusting powder.", "Although rare during normal use, talc is known to be potentially irritant to mucous membranes (such as in the vagina).", "Cornstarch is generally believed to be safe; however, some researchers have raised concerns over its use as well.Nitrosamines, which are potentially carcinogenic in humans, are believed to be present in a substance used to improve elasticity in latex condoms.", "A 2001 review stated that humans regularly receive 1,000 to 10,000 times greater nitrosamine exposure from food and tobacco than from condom use and concluded that the risk of cancer from condom use is very low.", "However, a 2004 study in Germany detected nitrosamines in 29 out of 32 condom brands tested, and concluded that exposure from condoms might exceed the exposure from food by 1.5- to 3-fold.Used condom on a streetIn addition, the large-scale use of disposable condoms has resulted in concerns over their environmental impact via littering and in landfills, where they can eventually wind up in wildlife environments if not incinerated or otherwise permanently disposed of first.", "Polyurethane condoms in particular, given they are a form of plastic, are not biodegradable, and latex condoms take a very long time to break down.", "Experts, such as AVERT, recommend condoms be disposed of in a garbage receptacle, as flushing them down the toilet (which some people do) may cause plumbing blockages and other problems.", "Furthermore, the plastic and foil wrappers condoms are packaged in are also not biodegradable.", "However, the benefits condoms offer are widely considered to offset their small landfill mass.", "Frequent condom or wrapper disposal in public areas such as a parks have been seen as a persistent litter problem.While biodegradable, latex condoms damage the environment when disposed of improperly.", "According to the Ocean Conservancy, condoms, along with certain other types of trash, cover the coral reefs and smother sea grass and other bottom dwellers.", "The United States Environmental Protection Agency also has expressed concerns that many animals might mistake the litter for food.=== Cultural barriers to use ===In much of the Western world, the introduction of the pill in the 1960s was associated with a decline in condom use.", "In Japan, oral contraceptives were not approved for use until September 1999, and even then access was more restricted than in other industrialized nations.", "Perhaps because of this restricted access to hormonal contraception, Japan has the highest rate of condom usage in the world: in 2008, 80% of contraceptive users relied on condoms.Cultural attitudes toward gender roles, contraception, and sexual activity vary greatly around the world, and range from extremely conservative to extremely liberal.", "But in places where condoms are misunderstood, mischaracterised, demonised, or looked upon with overall cultural disapproval, the prevalence of condom use is directly affected.", "In less-developed countries and among less-educated populations, misperceptions about how disease transmission and conception work negatively affect the use of condoms; additionally, in cultures with more traditional gender roles, women may feel uncomfortable demanding that their partners use condoms.As an example, Latino immigrants in the United States often face cultural barriers to condom use.", "A study on female HIV prevention published in the ''Journal of Sex Health Research'' asserts that Latino women often lack the attitudes needed to negotiate safe sex due to traditional gender-role norms in the Latino community, and may be afraid to bring up the subject of condom use with their partners.", "Women who participated in the study often reported that because of the general machismo subtly encouraged in Latino culture, their male partners would be angry or possibly violent at the woman's suggestion that they use condoms.", "A similar phenomenon has been noted in a survey of low-income American black women; the women in this study also reported a fear of violence at the suggestion to their male partners that condoms be used.A telephone survey conducted by Rand Corporation and Oregon State University, and published in the ''Journal of Acquired Immune Deficiency Syndromes'' showed that belief in AIDS conspiracy theories among United States black men is linked to rates of condom use.", "As conspiracy beliefs about AIDS grow in a given sector of these black men, consistent condom use drops in that same sector.", "Female use of condoms was not similarly affected.In the African continent, condom promotion in some areas has been impeded by anti-condom campaigns by some Muslim and Catholic clerics.", "Among the Maasai in Tanzania, condom use is hampered by an aversion to \"wasting\" sperm, which is given sociocultural importance beyond reproduction.", "Sperm is believed to be an \"elixir\" to women and to have beneficial health effects.", "Maasai women believe that, after conceiving a child, they must have sexual intercourse repeatedly so that the additional sperm aids the child's development.", "Frequent condom use is also considered by some Maasai to cause impotence.", "Some women in Africa believe that condoms are \"for prostitutes\" and that respectable women should not use them.", "A few clerics even promote the lie that condoms are deliberately laced with HIV.", "In the United States, possession of many condoms has been used by police to accuse women of engaging in prostitution.", "The Presidential Advisory Council on HIV/AIDS has condemned this practice and there are efforts to end it.Middle-Eastern couples who have not had children, because of the strong desire and social pressure to establish fertility as soon as possible within marriage, rarely use condoms.In 2017, India restricted TV advertisements for condoms to between the hours of 10 pm to 6 am.", "Family planning advocates were against this, saying it was liable to \"undo decades of progress on sexual and reproductive health\".=== Major manufacturers ===One analyst described the size of the condom market as something that \"boggles the mind\".", "Numerous small manufacturers, nonprofit groups, and government-run manufacturing plants exist around the world.", "Within the condom market, there are several major contributors, among them both for-profit businesses and philanthropic organizations.", "Most large manufacturers have ties to the business that reach back to the end of the 19th century.=== Economics ===In the United States condoms usually cost less than US$1.00." ], [ "Research", "A spray-on condom made of latex is intended to be easier to apply and more successful in preventing the transmission of diseases.", ", the spray-on condom was not going to market because the drying time could not be reduced below two to three minutes.The Invisible Condom, developed at Université Laval in Quebec, Canada, is a gel that hardens upon increased temperature after insertion into the vagina or rectum.", "In the lab, it has been shown to effectively block HIV and herpes simplex virus.", "The barrier breaks down and liquefies after several hours.", ", the invisible condom is in the clinical trial phase, and has not yet been approved for use.Also developed in 2005 is a condom treated with an erectogenic compound.", "The drug-treated condom is intended to help the wearer maintain his erection, which should also help reduce slippage.", "If approved, the condom would be marketed under the Durex brand.", ", it was still in clinical trials.", "In 2009, Ansell Healthcare, the makers of Lifestyle condoms, introduced the X2 condom lubricated with \"Excite Gel\" which contains the amino acid L-arginine and is intended to improve the strength of the erectile response.In March 2013, philanthropist Bill Gates offered US$100,000 grants through his foundation for a condom design that \"significantly preserves or enhances pleasure\" to encourage more males to adopt the use of condoms for safer sex.", "The grant information stated: \"The primary drawback from the male perspective is that condoms decrease pleasure as compared to no condom, creating a trade-off that many men find unacceptable, particularly given that the decisions about use must be made just prior to intercourse.", "Is it possible to develop a product without this stigma, or better, one that is felt to enhance pleasure?\"", "In November of the same year, 11 research teams were selected to receive the grant money." ], [ "References" ], [ "External links", "* WHO fact sheet on condoms* \" Sheathing Cupid's Arrow: the Oldest Artificial Contraceptive May Be Ripe for a Makeover\", ''The Economist'', February 2014." ] ]

[ [ "Country code" ], [ "Introduction", "A '''country code''' is a short alphanumeric identification code for countries and dependent areas.", "Its primary use is in data processing and communications.", "Several identification systems have been developed.The term ''country code'' frequently refers to ISO 3166-1 alpha-2, as well as the telephone country code, which is embodied in the E.164 recommendation by the International Telecommunication Union (ITU)." ], [ "ISO 3166-1", "The standard ISO 3166-1 defines short identification codes for most countries and dependent areas:*ISO 3166-1 alpha-2: two-letter code*ISO 3166-1 alpha-3: three-letter code*ISO 3166-1 numeric: three-digit codeThe two-letter codes are used as the basis for other codes and applications, for example,*for ISO 4217 currency codes*with deviations, for country code top-level domain names (ccTLDs) on the Internet: list of Internet TLDs.Other applications are defined in ISO 3166-1 alpha-2." ], [ "ITU country codes", "In telecommunication, a ''country code'', or ''international subscriber dialing'' (ISD) code, is a telephone number prefix used in international direct dialing (IDD) and for destination routing of telephone calls to a country other than the caller's.", "A country or region with an autonomous telephone administration must apply for membership in the International Telecommunication Union (ITU) to participate in the international public switched telephone network (PSTN).", "County codes are defined by the ITU-T section of the ITU in standards E.123 and E.164.Country codes constitute the international telephone numbering plan, and are dialed only when calling a telephone number in another country.", "They are dialed before the national telephone number.", "International calls require at least one additional prefix to be dialing before the country code, to connect the call to international circuits, the international call prefix.", "When printing telephone numbers this is indicated by a plus-sign (''+'') in front of a complete international telephone number, per recommendation E164 by the ITU." ], [ "Other country codes", "*European Union:**Before the 2004 EU enlargement the EU used the UN Road Traffic Conventions license plate codes.", "Since then, it has used the ISO 3166-1 alpha-2 code, but with two modifications:***EL for Greece (instead of GR)***(formerly) UK for United Kingdom (instead of GB)**The ''Nomenclature des unités territoriales statistiques'' (Nomenclature of territorial units for statistics, NUTS) of the European Union, mostly focusing on subdivisions of the EU member states*FIFA (Fédération Internationale de Football Association) assigns a three-letter code (dubbed FIFA Trigramme) to each of its member and non-member countries: List of FIFA country codes*Federal Information Processing Standard (FIPS) 10-4 defined two-letter codes used by the U.S. government and in the CIA World Factbook: list of FIPS country codes.", "On September 2, 2008, FIPS 10-4 was one of ten standards withdrawn by NIST as a Federal Information Processing Standard.", "* The Bureau of Transportation Statistics, part of the United States Department of Transportation (US DOT), maintains its own list of codes, so-called World Area Codes (WAC), for state and country codes.", "* GOST 7.67: country codes in Cyrillic from the GOST standards committee*From the International Civil Aviation Organization (ICAO):**The national prefixes used in aircraft registration numbers**Location prefixes in four-character ICAO airport codes*International Olympic Committee (IOC) three-letter codes used in sporting events: list of IOC country codes*From the International Telecommunication Union (ITU):**the E.212 mobile country codes (MCC), for mobile/wireless phone addresses,**the first few characters of call signs of radio stations (maritime, aeronautical, amateur radio, broadcasting, and so on) define the country: the ITU prefix,**ITU letter codes for member-countries,**ITU prefix - amateur and experimental stations - The International Telecommunication Union (ITU) assigns national telecommunication prefixes for amateur and experimental radio use, so that operators can be identified by their country of origin.", "These prefixes are legally administered by the national entity to which prefix ranges are assigned.", "**Three-digit codes used to identify countries in maritime mobile radio transmissions, known as maritime identification digits*License plates for automobiles:**Under the 1949 and 1968 United Nations Road Traffic Conventions (distinguishing signs of vehicles in international traffic): List of international license plate codes.", "**Diplomatic license plates in the United States, assigned by the U.S. State Department.", "*North Atlantic Treaty Organization (NATO) used two-letter codes of its own: list of NATO country codes.", "They were largely borrowed from the FIPS 10-4 codes mentioned below.", "In 2003 the eighth edition of the Standardisation Agreement (STANAG) adopted the ISO 3166 three-letter codes with one exception (the code for Macedonia).", "With the ninth edition, NATO is transitioning to four- and six-letter codes based on ISO 3166 with a few exceptions and additions*United Nations Development Programme (UNDP) also has its own list of trigram country codes* World Intellectual Property Organization (WIPO): WIPO ST.3 gives two-letter codes to countries and regional intellectual property organizations*World Meteorological Organization (WMO) maintains a list of country codes, used in reporting meteorological observations* UIC (the International Union of Railways): UIC Country CodesThe developers of ISO 3166 intended that in time it would replace other coding systems." ], [ "Other codings", "Country identities may be encoded in the following coding systems:*The initial digits of International Standard Book Numbers (ISBN) are group identifiers for countries, areas, or language regions.", "*The first three digits of GS1 Company Prefixes used to identify products, for example, in barcodes, designate (national) numbering agencies." ], [ "Lists of country codes by country", "A -B -C -D–E -F -G -H–I -J–K -L -M -N -O–Q -R -S -T -U–Z" ], [ "See also", "*List of ISO 3166 country codes*ISO 639 language codes*Language code*Numbering scheme" ], [ "References" ], [ "External links", "* Comparison of various systems*Another comparison: *A comparison with ISO, IFS and others with notes* United Nations Region Codes" ] ]

[ [ "Cladistics" ], [ "Introduction", "'''Cladistics''' (; ) is an approach to biological classification in which organisms are categorized in groups (\"clades\") based on hypotheses of most recent common ancestry.", "The evidence for hypothesized relationships is typically shared derived characteristics (synapomorphies) that are not present in more distant groups and ancestors.", "However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed.", "Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade.", "Importantly, all descendants stay in their overarching ancestral clade.", "For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans.", "Many of these terms are normally used paraphyletically, outside of cladistics, e.g.", "as a 'grade', which are fruitless to precisely delineate, especially when including extinct species.", "Radiation results in the generation of new subclades by bifurcation, but in practice sexual hybridization may blur very closely related groupings.As a hypothesis, a clade can be rejected only if some groupings were explicitly excluded.", "It may then be found that the excluded group did actually descend from the last common ancestor of the group, and thus emerged within the group.", "(\"Evolved from\" is misleading, because in cladistics all descendants stay in the ancestral group).", "To keep only valid clades, upon finding that the group is paraphyletic this way, either such excluded groups should be granted to the clade, or the group should be abolished.Branches down to the divergence to the next significant (e.g.", "extant) sister are considered stem-groupings of the clade, but in principle each level stands on its own, to be assigned a unique name.", "For a fully bifurcated tree, adding a group to a tree also adds an additional (named) clade, and a new level on that branch.", "Specifically, also extinct groups are always put on a side-branch, not distinguishing whether an actual ancestor of other groupings was found.The techniques and nomenclature of cladistics have been applied to disciplines other than biology.", "(See phylogenetic nomenclature.", ")Cladistics findings are posing a difficulty for taxonomy, where the rank and (genus-)naming of established groupings may turn out to be inconsistent.Cladistics is now the most commonly used method to classify organisms." ], [ "History", "Willi Hennig 1972Peter Chalmers Mitchell in 1920Robert John TillyardThe original methods used in cladistic analysis and the school of taxonomy derived from the work of the German entomologist Willi Hennig, who referred to it as '''phylogenetic systematics''' (also the title of his 1966 book); but the terms \"cladistics\" and \"clade\" were popularized by other researchers.", "Cladistics in the original sense refers to a particular set of methods used in phylogenetic analysis, although it is now sometimes used to refer to the whole field.What is now called the cladistic method appeared as early as 1901 with a work by Peter Chalmers Mitchell for birds and subsequently by Robert John Tillyard (for insects) in 1921, and W. Zimmermann (for plants) in 1943.The term \"clade\" was introduced in 1958 by Julian Huxley after having been coined by Lucien Cuénot in 1940, \"cladogenesis\" in 1958, \"cladistic\" by Arthur Cain and Harrison in 1960, \"cladist\" (for an adherent of Hennig's school) by Ernst Mayr in 1965, and \"cladistics\" in 1966.Hennig referred to his own approach as \"phylogenetic systematics\".", "From the time of his original formulation until the end of the 1970s, cladistics competed as an analytical and philosophical approach to systematics with phenetics and so-called evolutionary taxonomy.", "Phenetics was championed at this time by the numerical taxonomists Peter Sneath and Robert Sokal, and evolutionary taxonomy by Ernst Mayr.Originally conceived, if only in essence, by Willi Hennig in a book published in 1950, cladistics did not flourish until its translation into English in 1966 (Lewin 1997).", "Today, cladistics is the most popular method for inferring phylogenetic trees from morphological data.In the 1990s, the development of effective polymerase chain reaction techniques allowed the application of cladistic methods to biochemical and molecular genetic traits of organisms, vastly expanding the amount of data available for phylogenetics.", "At the same time, cladistics rapidly became popular in evolutionary biology, because computers made it possible to process large quantities of data about organisms and their characteristics." ], [ "Methodology", "The cladistic method interprets each shared character state transformation as a potential piece of evidence for grouping.", "Synapomorphies (shared, derived character states) are viewed as evidence of grouping, while symplesiomorphies (shared ancestral character states) are not.", "The outcome of a cladistic analysis is a cladogram – a tree-shaped diagram (dendrogram) that is interpreted to represent the best hypothesis of phylogenetic relationships.", "Although traditionally such cladograms were generated largely on the basis of morphological characters and originally calculated by hand, genetic sequencing data and computational phylogenetics are now commonly used in phylogenetic analyses, and the parsimony criterion has been abandoned by many phylogeneticists in favor of more \"sophisticated\" but less parsimonious evolutionary models of character state transformation.", "Cladists contend that these models are unjustified because there is no evidence that they recover more \"true\" or \"correct\" results from actual empirical data sets Every cladogram is based on a particular dataset analyzed with a particular method.", "Datasets are tables consisting of molecular, morphological, ethological and/or other characters and a list of operational taxonomic units (OTUs), which may be genes, individuals, populations, species, or larger taxa that are presumed to be monophyletic and therefore to form, all together, one large clade; phylogenetic analysis infers the branching pattern within that clade.", "Different datasets and different methods, not to mention violations of the mentioned assumptions, often result in different cladograms.", "Only scientific investigation can show which is more likely to be correct.Until recently, for example, cladograms like the following have generally been accepted as accurate representations of the ancestral relations among turtles, lizards, crocodilians, and birds:If this phylogenetic hypothesis is correct, then the last common ancestor of turtles and birds, at the branch near the lived earlier than the last common ancestor of lizards and birds, near the .", "Most molecular evidence, however, produces cladograms more like this:If this is accurate, then the last common ancestor of turtles and birds lived later than the last common ancestor of lizards and birds.", "Since the cladograms show two mutually exclusive hypotheses to describe the evolutionary history, at most one of them is correct.Cladogram of the primates, showing a monophyletic taxon (a clade: the simians or Anthropoidea, in yellow), a paraphyletic taxon (the prosimians, in blue, including the red patch), and a polyphyletic taxon (the nocturnal primates – the lorises and the tarsiers – in red)The cladogram to the right represents the current universally accepted hypothesis that all primates, including strepsirrhines like the lemurs and lorises, had a common ancestor all of whose descendants are or were primates, and so form a clade; the name Primates is therefore recognized for this clade.", "Within the primates, all anthropoids (monkeys, apes, and humans) are hypothesized to have had a common ancestor all of whose descendants are or were anthropoids, so they form the clade called Anthropoidea.", "The \"prosimians\", on the other hand, form a paraphyletic taxon.", "The name Prosimii is not used in phylogenetic nomenclature, which names only clades; the \"prosimians\" are instead divided between the clades Strepsirhini and Haplorhini, where the latter contains Tarsiiformes and Anthropoidea.Lemurs and tarsiers may have looked closely related to humans, in the sense of being close on the evolutionary tree to humans.", "However, from the perspective of a tarsier, humans and lemurs would have looked close, in the exact same sense.", "Cladistics forces a neutral perspective, treating all branches (extant or extinct) in the same manner.", "It also forces one to try to make statements, and honestly take into account findings, about the exact historic relationships between the groups." ], [ "Terminology for character states", "The following terms, coined by Hennig, are used to identify shared or distinct character states among groups:* A '''plesiomorphy''' (\"close form\") or '''ancestral state''' is a character state that a taxon has retained from its ancestors.", "When two or more taxa that are not nested within each other share a plesiomorphy, it is a '''symplesiomorphy''' (from ''syn-'', \"together\").", "Symplesiomorphies do not mean that the taxa that exhibit that character state are necessarily closely related.", "For example, Reptilia is traditionally characterized by (among other things) being cold-blooded (i.e., not maintaining a constant high body temperature), whereas birds are warm-blooded.", "Since cold-bloodedness is a plesiomorphy, inherited from the common ancestor of traditional reptiles and birds, and thus a symplesiomorphy of turtles, snakes and crocodiles (among others), it does not mean that turtles, snakes and crocodiles form a clade that excludes the birds.", "* An '''apomorphy''' (\"separate form\") or '''derived state''' is an innovation.", "It can thus be used to diagnose a clade – or even to help define a clade name in phylogenetic nomenclature.", "Features that are derived in individual taxa (a single species or a group that is represented by a single terminal in a given phylogenetic analysis) are called '''autapomorphies''' (from ''auto-'', \"self\").", "Autapomorphies express nothing about relationships among groups; clades are identified (or defined) by '''synapomorphies''' (from ''syn-'', \"together\").", "For example, the possession of digits that are homologous with those of ''Homo sapiens'' is a synapomorphy within the vertebrates.", "The tetrapods can be singled out as consisting of the first vertebrate with such digits homologous to those of ''Homo sapiens'' together with all descendants of this vertebrate (an apomorphy-based phylogenetic definition).", "Importantly, snakes and other tetrapods that do not have digits are nonetheless tetrapods: other characters, such as amniotic eggs and diapsid skulls, indicate that they descended from ancestors that possessed digits which are homologous with ours.", "* A character state is '''homoplastic''' or \"an instance of '''homoplasy'''\" if it is shared by two or more organisms but is absent from their common ancestor or from a later ancestor in the lineage leading to one of the organisms.", "It is therefore inferred to have evolved by convergence or reversal.", "Both mammals and birds are able to maintain a high constant body temperature (i.e., they are warm-blooded).", "However, the accepted cladogram explaining their significant features indicates that their common ancestor is in a group lacking this character state, so the state must have evolved independently in the two clades.", "Warm-bloodedness is separately a synapomorphy of mammals (or a larger clade) and of birds (or a larger clade), but it is not a synapomorphy of any group including both these clades.", "Hennig's Auxiliary Principle states that shared character states should be considered evidence of grouping unless they are contradicted by the weight of other evidence; thus, homoplasy of some feature among members of a group may only be inferred after a phylogenetic hypothesis for that group has been established.The terms plesiomorphy and apomorphy are relative; their application depends on the position of a group within a tree.", "For example, when trying to decide whether the tetrapods form a clade, an important question is whether having four limbs is a synapomorphy of the earliest taxa to be included within Tetrapoda: did all the earliest members of the Tetrapoda inherit four limbs from a common ancestor, whereas all other vertebrates did not, or at least not homologously?", "By contrast, for a group within the tetrapods, such as birds, having four limbs is a plesiomorphy.", "Using these two terms allows a greater precision in the discussion of homology, in particular allowing clear expression of the hierarchical relationships among different homologous features.It can be difficult to decide whether a character state is in fact the same and thus can be classified as a synapomorphy, which may identify a monophyletic group, or whether it only appears to be the same and is thus a homoplasy, which cannot identify such a group.", "There is a danger of circular reasoning: assumptions about the shape of a phylogenetic tree are used to justify decisions about character states, which are then used as evidence for the shape of the tree.", "Phylogenetics uses various forms of parsimony to decide such questions; the conclusions reached often depend on the dataset and the methods.", "Such is the nature of empirical science, and for this reason, most cladists refer to their cladograms as hypotheses of relationship.", "Cladograms that are supported by a large number and variety of different kinds of characters are viewed as more robust than those based on more limited evidence." ], [ "Terminology for taxa", "Mono-, para- and polyphyletic taxa can be understood based on the shape of the tree (as done above), as well as based on their character states.", "These are compared in the table below.+ Term Node-based definition Character-based definition Holophyly, Monophyly A clade, a monophyletic taxon, is a taxon that consists of the last common ancestor and all its descendants.", "A clade is characterized by one or more '''apomorphies''': derived character states present in the first member of the taxon, inherited by its descendants (unless secondarily lost), and not inherited by any other taxa.", "Paraphyly A paraphyletic assemblage is one that is constructed by taking a clade and removing one or more smaller clades.", "(Removing one clade produces a singly paraphyletic assemblage, removing two produces a doubly paraphylectic assemblage, and so on.)", "A paraphyletic assemblage is characterized by one or more '''plesiomorphies''': character states inherited from ancestors but not present in all of their descendants.", "As a consequence, a paraphyletic assemblage is truncated, in that it excludes one or more clades from an otherwise monophyletic taxon.", "An alternative name is ''evolutionary grade'', referring to an ancestral character state within the group.", "While paraphyletic assemblages are popular among paleontologists and evolutionary taxonomists, cladists do not recognize paraphyletic assemblages as having any formal information content – they are merely parts of clades.", "Polyphyly A polyphyletic assemblage is one which is neither monophyletic nor paraphyletic.", "A polyphyletic assemblage is characterized by one or more '''homoplasies''': character states which have converged or reverted so as to be the same but which have not been inherited from a common ancestor.", "No systematist recognizes polyphyletic assemblages as taxonomically meaningful entities, although ecologists sometimes consider them meaningful labels for functional participants in ecological communities (e. g., primary producers, detritivores, etc.", ")." ], [ "Criticism", "Cladistics, either generally or in specific applications, has been criticized from its beginnings.", "Decisions as to whether particular character states are homologous, a precondition of their being synapomorphies, have been challenged as involving circular reasoning and subjective judgements.", "Of course, the potential unreliability of evidence is a problem for any systematic method, or for that matter, for any empirical scientific endeavor at all.Transformed cladistics arose in the late 1970s in an attempt to resolve some of these problems by removing a priori assumptions about phylogeny from cladistic analysis, but it has remained unpopular." ], [ "Issues", "=== Ancestors ===The cladistic method does not identify fossil species as actual ancestors of a clade.", "Instead, fossil taxa are identified as belonging to separate extinct branches.", "While a fossil species could be the actual ancestor of a clade, there is no way to know that.", "Therefore, a more conservative hypothesis is that the fossil taxon is related to other fossil and extant taxa, as implied by the pattern of shared apomorphic features.=== Extinction status ===An otherwise extinct group with any extant descendants, is not considered (literally) extinct, and for instance does not have a date of extinction.=== Hybridization, interbreeding ===Anything having to do with biology and sex is complicated and messy, and cladistics is no exception.", "Many species reproduce sexually, and are capable of interbreeding for millions of years.", "Worse, during such a period, many branches may have radiated, and it may take hundreds of millions of years for them to have whittled down to just two.", "Only then one can theoretically assign proper last common ancestors of groupings which do not inadvertently include earlier branches.", "The process of true cladistic bifurcation can thus take a much more extended time than one is usually aware of.", "In practice, for recent radiations, cladistically guided findings only give a coarse impression of the complexity.", "A more detailed account will give details about fractions of introgressions between groupings, and even geographic variations thereof.", "This has been used as an argument for the use of paraphyletic groupings, but typically other reasons are quoted.=== Horizontal gene transfer ===Horizontal gene transfer is the mobility of genetic info between different organisms that can have immediate or delayed effects for the reciprocal host.", "There are several processes in nature which can cause horizontal gene transfer.", "This does typically not directly interfere with ancestry of the organism, but can complicate the determination of that ancestry.", "On another level, one can map the horizontal gene transfer processes, by determining the phylogeny of the individual genes using cladistics.=== Naming stability ===If there is unclarity in mutual relationships, there are a lot of possible trees.", "Assigning names to each possible clade may not be prudent.", "Furthermore, established names are discarded in cladistics, or alternatively carry connotations which may no longer hold, such as when additional groups are found to have emerged in them.", "Naming changes are the direct result of changes in the recognition of mutual relationships, which often is still in flux, especially for extinct species.", "Hanging on to older naming and/or connotations is counter-productive, as they typically do not reflect actual mutual relationships precisely at all.", "E.g.", "Archaea, Asgard archaea, protists, slime molds, worms, invertebrata, fishes, reptilia, monkeys, ''Ardipithecus'', ''Australopithecus'', ''Homo erectus'' all contain ''Homo sapiens'' cladistically, in their ''sensu lato'' meaning.", "For originally extinct stem groups, ''sensu lato'' generally means generously keeping previously included groups, which then may come to include even living species.", "A pruned ''sensu stricto'' meaning is often adopted instead, but the group would need to be restricted to a single branch on the stem.", "Other branches then get their own name and level.", "This is commensurate to the fact that more senior stem branches are in fact closer related to the resulting group than the more basal stem branches; that those stem branches only may have lived for a short time does not affect that assessment in cladistics." ], [ "In disciplines other than biology", "The comparisons used to acquire data on which cladograms can be based are not limited to the field of biology.", "Any group of individuals or classes that are hypothesized to have a common ancestor, and to which a set of common characteristics may or may not apply, can be compared pairwise.", "Cladograms can be used to depict the hypothetical descent relationships within groups of items in many different academic realms.", "The only requirement is that the items have characteristics that can be identified and measured.Anthropology and archaeology: Cladistic methods have been used to reconstruct the development of cultures or artifacts using groups of cultural traits or artifact features.Comparative mythology and folktale use cladistic methods to reconstruct the protoversion of many myths.", "Mythological phylogenies constructed with mythemes clearly support low horizontal transmissions (borrowings), historical (sometimes Palaeolithic) diffusions and punctuated evolution.", "They also are a powerful way to test hypotheses about cross-cultural relationships among folktales.Literature: Cladistic methods have been used in the classification of the surviving manuscripts of the ''Canterbury Tales'', and the manuscripts of the Sanskrit ''Charaka Samhita''.Historical linguistics: Cladistic methods have been used to reconstruct the phylogeny of languages using linguistic features.", "This is similar to the traditional comparative method of historical linguistics, but is more explicit in its use of parsimony and allows much faster analysis of large datasets (computational phylogenetics).Textual criticism or stemmatics: Cladistic methods have been used to reconstruct the phylogeny of manuscripts of the same work (and reconstruct the lost original) using distinctive copying errors as apomorphies.", "This differs from traditional historical-comparative linguistics in enabling the editor to evaluate and place in genetic relationship large groups of manuscripts with large numbers of variants that would be impossible to handle manually.", "It also enables parsimony analysis of contaminated traditions of transmission that would be impossible to evaluate manually in a reasonable period of time.Astrophysics infers the history of relationships between galaxies to create branching diagram hypotheses of galaxy diversification." ], [ "See also", "* Bioinformatics* Biomathematics* Coalescent theory* Common descent* Glossary of scientific naming* Language family* Patrocladogram* Phylogenetic network* Scientific classification* Stratocladistics* Subclade* Systematics* Three-taxon analysis* Tree model* Tree structure" ], [ "Notes and references" ], [ "Bibliography", "* * * * * * * Available free online at Gallica (No direct URL).", "This is the paper credited by for the first use of the term 'clade'.", "* * * * * * * * * responding to .", "* Translated from manuscript in German eventually published in 1982 (Phylogenetische Systematik, Verlag Paul Parey, Berlin).", "* * * * d'Huy, Julien (2012b), \"Le motif de Pygmalion : origine afrasienne et diffusion en Afrique\".", "''Sahara'', 23: 49-59 .", "* d'Huy, Julien (2013a), \"Polyphemus (Aa.", "Th.", "1137).\"", "\"A phylogenetic reconstruction of a prehistoric tale\".", "''Nouvelle Mythologie Comparée / New Comparative Mythology'' 1, * * d'Huy, Julien (2013c) \"Les mythes évolueraient par ponctuations\".", "''Mythologie française'', 252, 2013c: 8-12.", "* d'Huy, Julien (2013d) \"A Cosmic Hunt in the Berber sky : a phylogenetic reconstruction of Palaeolithic mythology\".", "''Les Cahiers de l'AARS'', 15, 2013d: 93-106.", "* * * * * * * Reissued 1997 in paperback.", "Includes a reprint of Mayr's 1974 anti-cladistics paper at pp.", "433–476, \"Cladistic analysis or cladistic classification.\"", "This is the paper to which is a response.", "* * * * .", "* * * * * * * * Tehrani, Jamshid J., 2013, \"The Phylogeny of Little Red Riding Hood\", ''PLOS ONE'', 13 November.", "* * * * *" ], [ "External links", "* * OneZoom: Tree of Life – all living species as intuitive and zoomable fractal explorer (responsive design)* Willi Hennig Society* Cladistics (scholarly journal of the Willi Hennig Society)* * * * *" ] ]

[ [ "Calendar" ], [ "Introduction", "Modern day Indonesian Gregorian calendar for a Catholic churchBritish calendar, 1851, gilt bronze and malachite, height: 20.3 cm, Metropolitan Museum of Art (New York City)A '''calendar''' is a system of organizing days.", "This is done by giving names to periods of time, typically days, weeks, months and years.", "A date is the designation of a single and specific day within such a system.", "A calendar is also a physical record (often paper) of such a system.", "A calendar can also mean a list of planned events, such as a court calendar, or a partly or fully chronological list of documents, such as a calendar of wills.Periods in a calendar (such as years and months) are usually, though not necessarily, synchronized with the cycle of the sun or the moon.", "The most common type of pre-modern calendar was the lunisolar calendar, a lunar calendar that occasionally adds one intercalary month to remain synchronized with the solar year over the long term." ], [ "Etymology", "The term ''calendar'' is taken from , the term for the first day of the month in the Roman calendar, related to the verb 'to call out', referring to the \"calling\" of the new moon when it was first seen.", "Latin meant 'account book, register' (as accounts were settled and debts were collected on the calends of each month).", "The Latin term was adopted in Old French as and from there in Middle English as by the 13th century (the spelling ''calendar'' is early modern)." ], [ "History", "Equinox seen from the astronomic calendar of Pizzo Vento at Fondachelli Fantina, SicilyThe course of the Sun and the Moon are the most salient regularly recurring natural events useful for timekeeping, and in pre-modern societies around the world lunation and the year were most commonly used as time units.", "Nevertheless, the Roman calendar contained remnants of a very ancient pre-Etruscan 10-month solar year.", "The first recorded physical calendars, dependent on the development of writing in the Ancient Near East, are the Bronze Age Egyptian and Sumerian calendars.During the Vedic period India developed a sophisticated timekeeping methodology and calendars for Vedic rituals.", "According to Yukio Ohashi, the Vedanga calendar in ancient India was based on astronomical studies during the Vedic Period and was not derived from other cultures.A large number of calendar systems in the Ancient Near East were based on the Babylonian calendar dating from the Iron Age, among them the calendar system of the Persian Empire, which in turn gave rise to the Zoroastrian calendar and the Hebrew calendar.", "A great number of Hellenic calendars were developed in Classical Greece, and during the Hellenistic period they gave rise to the ancient Roman calendar and to various Hindu calendars.", "Calendars in antiquity were lunisolar, depending on the introduction of intercalary months to align the solar and the lunar years.", "This was mostly based on observation, but there may have been early attempts to model the pattern of intercalation algorithmically, as evidenced in the fragmentary 2nd-century Coligny calendar.The Roman calendar was reformed by Julius Caesar in 46 BC.", "His \"Julian\" calendar was no longer dependent on the observation of the new moon, but followed an algorithm of introducing a leap day every four years.", "This created a dissociation of the calendar month from lunation.", "The Gregorian calendar, introduced in 1582, corrected most of the remaining difference between the Julian calendar and the solar year.The Islamic calendar is based on the prohibition of intercalation (''nasi''') by Muhammad, in Islamic tradition dated to a sermon given on 9 Dhu al-Hijjah AH 10 (Julian date: 6 March 632).", "This resulted in an observation-based lunar calendar that shifts relative to the seasons of the solar year.There have been several modern proposals for reform of the modern calendar, such as the World Calendar, the International Fixed Calendar, the Holocene calendar, and the Hanke–Henry Permanent Calendar.", "Such ideas are mooted from time to time, but have failed to gain traction because of the loss of continuity and the massive upheaval that implementing them would involve, as well as their effect on cycles of religious activity." ], [ "Systems", "A so-called universal calendar, combining different calendarsA full calendar system has a different calendar date for every day.", "Thus the week cycle is by itself not a full calendar system; neither is a system to name the days within a year without a system for identifying the years.The simplest calendar system just counts time periods from a reference date.", "This applies for the Julian day or Unix Time.", "Virtually the only possible variation is using a different reference date, in particular, one less distant in the past to make the numbers smaller.", "Computations in these systems are just a matter of addition and subtraction.Other calendars have one (or multiple) larger units of time.Calendars that contain one level of cycles:* week and weekday – this system (without year, the week number keeps on increasing) is not very common* year and ordinal date within the year, e.g., the ISO 8601 ordinal date systemCalendars with two levels of cycles:* year, month, and day – most systems, including the Gregorian calendar (and its very similar predecessor, the Julian calendar), the Islamic calendar, the Solar Hijri calendar and the Hebrew calendar* year, week, and weekday – e.g., the ISO week dateCycles can be synchronized with periodic phenomena:Sun and Moon, Schedel's Nuremberg Chronicle, 1493* Lunar calendars are synchronized to the motion of the Moon (lunar phases); an example is the Islamic calendar.", "* Solar calendars are based on perceived seasonal changes synchronized to the apparent motion of the Sun; an example is the Persian calendar.", "* Lunisolar calendars are based on a combination of both solar and lunar reckonings; examples include the traditional calendar of China, the Hindu calendar in India and Nepal, and the Hebrew calendar.", "* The week cycle is an example of one that is not synchronized to any external phenomenon (although it may have been derived from lunar phases, beginning anew every month).Very commonly a calendar includes more than one type of cycle or has both cyclic and non-cyclic elements.Most calendars incorporate more complex cycles.", "For example, the vast majority of them track years, months, weeks and days.", "The seven-day week is practically universal, though its use varies.", "It has run uninterrupted for millennia.===Solar===Solar calendars assign a ''date'' to each solar day.", "A day may consist of the period between sunrise and sunset, with a following period of night, or it may be a period between successive events such as two sunsets.", "The length of the interval between two such successive events may be allowed to vary slightly during the year, or it may be averaged into a mean solar day.", "Other types of calendar may also use a solar day.===Lunar===Not all calendars use the solar year as a unit.", "A lunar calendar is one in which days are numbered within each lunar phase cycle.", "Because the length of the lunar month is not an even fraction of the length of the tropical year, a purely lunar calendar quickly drifts against the seasons, which do not vary much near the equator.", "It does, however, stay constant with respect to other phenomena, notably tides.", "An example is the Islamic calendar.Alexander Marshack, in a controversial reading, believed that marks on a bone baton () represented a lunar calendar.", "Other marked bones may also represent lunar calendars.", "Similarly, Michael Rappenglueck believes that marks on a 15,000-year-old cave painting represent a lunar calendar.===Lunisolar===A lunisolar calendar is a lunar calendar that compensates by adding an extra month as needed to realign the months with the seasons.", "Prominent examples of lunisolar calendar are Hindu calendar and Buddhist calendar that are popular in South Asia and Southeast Asia.", "Another example is the Hebrew calendar, which uses a 19-year cycle." ], [ "Subdivisions", "Catalan early 20th century perpetual calendarNearly all calendar systems group consecutive days into \"months\" and also into \"years\".", "In a ''solar calendar'' a ''year'' approximates Earth's tropical year (that is, the time it takes for a complete cycle of seasons), traditionally used to facilitate the planning of agricultural activities.", "In a ''lunar calendar'', the ''month'' approximates the cycle of the moon phase.", "Consecutive days may be grouped into other periods such as the week.Because the number of days in the ''tropical year'' is not a whole number, a solar calendar must have a different number of days in different years.", "This may be handled, for example, by adding an extra day in leap years.", "The same applies to months in a lunar calendar and also the number of months in a year in a lunisolar calendar.", "This is generally known as intercalation.", "Even if a calendar is solar, but not lunar, the year cannot be divided entirely into months that never vary in length.Cultures may define other units of time, such as the week, for the purpose of scheduling regular activities that do not easily coincide with months or years.", "Many cultures use different baselines for their calendars' starting years.", "Historically, several countries have based their calendars on regnal years, a calendar based on the reign of their current sovereign.", "For example, the year 2006 in Japan is year 18 Heisei, with Heisei being the era name of Emperor Akihito." ], [ "Other types", "===Arithmetical and astronomical===Calendar of the Qahal, 5591 (1831)An ''astronomical calendar'' is based on ongoing observation; examples are the religious Islamic calendar and the old religious Jewish calendar in the time of the Second Temple.", "Such a calendar is also referred to as an ''observation-based'' calendar.", "The advantage of such a calendar is that it is perfectly and perpetually accurate.", "The disadvantage is that working out when a particular date would occur is difficult.An ''arithmetic calendar'' is one that is based on a strict set of rules; an example is the current Jewish calendar.", "Such a calendar is also referred to as a ''rule-based'' calendar.", "The advantage of such a calendar is the ease of calculating when a particular date occurs.", "The disadvantage is imperfect accuracy.", "Furthermore, even if the calendar is very accurate, its accuracy diminishes slowly over time, owing to changes in Earth's rotation.", "This limits the lifetime of an accurate arithmetic calendar to a few thousand years.", "After then, the rules would need to be modified from observations made since the invention of the calendar.===Complete and incomplete===Calendars may be either complete or incomplete.", "Complete calendars provide a way of naming each consecutive day, while incomplete calendars do not.", "The early Roman calendar, which had no way of designating the days of the winter months other than to lump them together as \"winter\", is an example of an incomplete calendar, while the Gregorian calendar is an example of a complete calendar." ], [ "Usage", "Chinese or Islamic calendars.The primary practical use of a calendar is to identify days: to be informed about or to agree on a future event and to record an event that has happened.", "Days may be significant for agricultural, civil, religious, or social reasons.", "For example, a calendar provides a way to determine when to start planting or harvesting, which days are religious or civil holidays, which days mark the beginning and end of business accounting periods, and which days have legal significance, such as the day taxes are due or a contract expires.", "Also, a calendar may, by identifying a day, provide other useful information about the day such as its season.Calendars are also used as part of a complete timekeeping system: date and time of day together specify a moment in time.", "In the modern world, timekeepers can show time, date, and weekday.", "Some may also show the lunar phase.===Gregorian===The Gregorian calendar is the ''de facto'' international standard and is used almost everywhere in the world for civil purposes.", "The widely-used solar aspect is a cycle of leap days in a 400-year cycle designed to keep the duration of the year aligned with the solar year.", "There is a lunar aspect which approximates the position of the moon during the year, and is used in the calculation of the date of Easter.", "Each Gregorian year has either 365 or 366 days (the leap day being inserted as 29 February), amounting to an average Gregorian year of 365.2425 days (compared to a solar year of 365.2422 days).The calendar was introduced in 1582 as a refinement to the Julian calendar, which had been in use throughout the European Middle Ages, amounting to a 0.002% correction in the length of the year.", "During the Early Modern period, its adoption was mostly limited to Roman Catholic nations, but by the 19th century it had become widely adopted for the sake of convenience in international trade.", "The last European country to adopt it was Greece, in 1923.The calendar epoch used by the Gregorian calendar is inherited from the medieval convention established by Dionysius Exiguus and associated with the Julian calendar.", "The year number is variously given as AD (for ''Anno Domini'') or CE (for ''Common Era'' or ''Christian Era'').===Religious===A Hindu almanac (''pancanga'') for the year 1871/2 from Rajasthan (Library of Congress, Asian Division)The most important use of pre-modern calendars is keeping track of the liturgical year and the observation of religious feast days.While the Gregorian calendar is itself historically motivated to the calculation of the Easter date, it is now in worldwide secular use as the ''de facto'' standard.", "Alongside the use of the Gregorian calendar for secular matters, there remain several calendars in use for religious purposes.Western Christian liturgical calendars are based on the cycle of the Roman Rite of the Catholic Church and generally include the liturgical seasons of Advent, Christmas, Ordinary Time (Time after Epiphany), Lent, Easter, and Ordinary Time (Time after Pentecost).", "Some Christian calendars do not include Ordinary Time and every day falls into a denominated season.Eastern Christians, including the Orthodox Church, use the Julian calendar.The Islamic calendar or Hijri calendar is a lunar calendar consisting of 12 lunar months in a year of 354 or 355 days.", "It is used to date events in most of the Muslim countries (concurrently with the Gregorian calendar) and used by Muslims everywhere to determine the proper day on which to celebrate Islamic holy days and festivals.", "Its epoch is the Hijra (corresponding to AD 622).", "With an annual drift of 11 or 12 days, the seasonal relation is repeated approximately every 33 Islamic years.Various Hindu calendars remain in use in the Indian subcontinent, including the Nepali calendars, Bengali calendar, Malayalam calendar, Tamil calendar, Vikrama Samvat used in Northern India, and Shalivahana calendar in the Deccan states.The Buddhist calendar and the traditional lunisolar calendars of Cambodia, Laos, Myanmar, Sri Lanka and Thailand are also based on an older version of the Hindu calendar.Most of the Hindu calendars are inherited from a system first enunciated in Vedanga Jyotisha of Lagadha, standardized in the ''Sūrya Siddhānta'' and subsequently reformed by astronomers such as Āryabhaṭa (AD 499), Varāhamihira (6th century) and Bhāskara II (12th century).The Hebrew calendar is used by Jews worldwide for religious and cultural affairs, also influences civil matters in Israel (such as national holidays) and can be used business dealings (such as for the dating of cheques).Followers of the Baháʼí Faith use the Baháʼí calendar.", "The Baháʼí Calendar, also known as the Badi Calendar was first established by the Bab in the Kitab-i-Asma.", "The Baháʼí Calendar is also purely a solar calendar and comprises 19 months each having nineteen days.===National===The Chinese, Hebrew, Hindu, and Julian calendars are widely used for religious and social purposes.The Iranian (Persian) calendar is used in Iran and some parts of Afghanistan.", "The Assyrian calendar is in use by the members of the Assyrian community in the Middle East (mainly Iraq, Syria, Turkey, and Iran) and the diaspora.", "The first year of the calendar is exactly 4750 years prior to the start of the Gregorian calendar.", "The Ethiopian calendar or Ethiopic calendar is the principal calendar used in Ethiopia and Eritrea, with the Oromo calendar also in use in some areas.", "In neighboring Somalia, the Somali calendar co-exists alongside the Gregorian and Islamic calendars.", "In Thailand, where the Thai solar calendar is used, the months and days have adopted the western standard, although the years are still based on the traditional Buddhist calendar.===Fiscal===''The Payment of the Tithes'' (The tax-collector), also known as ''Village Lawyer'', by Pieter Brueghel the Younger A fiscal calendar generally means the accounting year of a government or a business.", "It is used for budgeting, keeping accounts, and taxation.", "It is a set of 12 months that may start at any date in a year.", "The US government's fiscal year starts on 1 October and ends on 30 September.", "The government of India's fiscal year starts on 1 April and ends on 31 March.", "Small traditional businesses in India start the fiscal year on Diwali festival and end the day before the next year's Diwali festival.In accounting (and particularly accounting software), a fiscal calendar (such as a 4/4/5 calendar) fixes each month at a specific number of weeks to facilitate comparisons from month to month and year to year.", "January always has exactly 4 weeks (Sunday through Saturday), February has 4 weeks, March has 5 weeks, etc.", "Note that this calendar will normally need to add a 53rd week to every 5th or 6th year, which might be added to December or might not be, depending on how the organization uses those dates.", "There exists an international standard way to do this (the ISO week).", "The ISO week starts on a Monday and ends on a Sunday.", "Week 1 is always the week that contains 4 January in the Gregorian calendar." ], [ "Formats", "A calendar from the Petaluma and Santa Rosa RailroadThe term ''calendar'' applies not only to a given scheme of timekeeping but also to a specific record or device displaying such a scheme, for example, an appointment book in the form of a pocket calendar (or personal organizer), desktop calendar, a wall calendar, etc.In a paper calendar, one or two sheets can show a single day, a week, a month, or a year.", "If a sheet is for a single day, it easily shows the date and the weekday.", "If a sheet is for multiple days it shows a conversion table to convert from weekday to date and back.", "With a special pointing device, or by crossing out past days, it may indicate the current date and weekday.", "This is the most common usage of the word.In the US Sunday is considered the first day of the week and so appears on the far left and Saturday the last day of the week appearing on the far right.", "In Britain, the weekend may appear at the end of the week so the first day is Monday and the last day is Sunday.", "The US calendar display is also used in Britain.It is common to display the Gregorian calendar in separate monthly grids of seven columns (from Monday to Sunday, or Sunday to Saturday depending on which day is considered to start the week – this varies according to country) and five to six rows (or rarely, four rows when the month of February contains 28 days in common years beginning on the first day of the week), with the day of the month numbered in each cell, beginning with 1.The sixth row is sometimes eliminated by marking 23/30 and 24/31 together as necessary.When working with weeks rather than months, a continuous format is sometimes more convenient, where no blank cells are inserted to ensure that the first day of a new month begins on a fresh row." ], [ "Software", "Calendaring software provides users with an electronic version of a calendar, and may additionally provide an appointment book, address book, or contact list.Calendaring is a standard feature of many PDAs, EDAs, and smartphones.", "The software may be a local package designed for individual use (e.g., Lightning extension for Mozilla Thunderbird, Microsoft Outlook without Exchange Server, or Windows Calendar) or maybe a networked package that allows for the sharing of information between users (e.g., Mozilla Sunbird, Windows Live Calendar, Google Calendar, or Microsoft Outlook with Exchange Server)." ], [ "See also", "* General Roman Calendar* List of calendars* Advent calendar* Calendar reform* Calendrical calculation* Docket (court)* History of calendars* Horology* List of international common standards* List of unofficial observances by date* Real-time clock (RTC), which underlies the Calendar software on modern computers.", "* Unit of time" ], [ "References", "=== Citations ====== Sources ===* * * * * * * * * * *" ], [ "Further reading", "* * * *" ], [ "External links", "* * * * Calendar converter, including all major civil, religious and technical calendars." ] ]

[ [ "Physical cosmology" ], [ "Introduction", "Artist conception of the Big Bang cosmological model, the most widely accepted out of all in physical cosmology (neither time nor size to scale)'''Physical cosmology''' is a branch of cosmology concerned with the study of cosmological models.", "A '''cosmological model''', or simply '''cosmology''', provides a description of the largest-scale structures and dynamics of the universe and allows study of fundamental questions about its origin, structure, evolution, and ultimate fate.", "Cosmology as a science originated with the Copernican principle, which implies that celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics, which first allowed those physical laws to be understood.Physical cosmology, as it is now understood, began with the development in 1915 of Albert Einstein's general theory of relativity, followed by major observational discoveries in the 1920s: first, Edwin Hubble discovered that the universe contains a huge number of external galaxies beyond the Milky Way; then, work by Vesto Slipher and others showed that the universe is expanding.", "These advances made it possible to speculate about the origin of the universe, and allowed the establishment of the Big Bang theory, by Georges Lemaître, as the leading cosmological model.", "A few researchers still advocate a handful of alternative cosmologies; however, most cosmologists agree that the Big Bang theory best explains the observations.Dramatic advances in observational cosmology since the 1990s, including the cosmic microwave background, distant supernovae and galaxy redshift surveys, have led to the development of a standard model of cosmology.", "This model requires the universe to contain large amounts of dark matter and dark energy whose nature is currently not well understood, but the model gives detailed predictions that are in excellent agreement with many diverse observations.Cosmology draws heavily on the work of many disparate areas of research in theoretical and applied physics.", "Areas relevant to cosmology include particle physics experiments and theory, theoretical and observational astrophysics, general relativity, quantum mechanics, and plasma physics." ], [ "Subject history", "Modern cosmology developed along tandem tracks of theory and observation.", "In 1916, Albert Einstein published his theory of general relativity, which provided a unified description of gravity as a geometric property of space and time.", "At the time, Einstein believed in a static universe, but found that his original formulation of the theory did not permit it.", "This is because masses distributed throughout the universe gravitationally attract, and move toward each other over time.", "However, he realized that his equations permitted the introduction of a constant term which could counteract the attractive force of gravity on the cosmic scale.", "Einstein published his first paper on relativistic cosmology in 1917, in which he added this ''cosmological constant'' to his field equations in order to force them to model a static universe.", "The Einstein model describes a static universe; space is finite and unbounded (analogous to the surface of a sphere, which has a finite area but no edges).", "However, this so-called Einstein model is unstable to small perturbations—it will eventually start to expand or contract.", "It was later realized that Einstein's model was just one of a larger set of possibilities, all of which were consistent with general relativity and the cosmological principle.", "The cosmological solutions of general relativity were found by Alexander Friedmann in the early 1920s.", "His equations describe the Friedmann–Lemaître–Robertson–Walker universe, which may expand or contract, and whose geometry may be open, flat, or closed.History of the Universe – gravitational waves are hypothesized to arise from cosmic inflation, a rapidly accelerated expansion just after the Big BangIn the 1910s, Vesto Slipher (and later Carl Wilhelm Wirtz) interpreted the red shift of spiral nebulae as a Doppler shift that indicated they were receding from Earth.", "However, it is difficult to determine the distance to astronomical objects.", "One way is to compare the physical size of an object to its angular size, but a physical size must be assumed to do this.", "Another method is to measure the brightness of an object and assume an intrinsic luminosity, from which the distance may be determined using the inverse-square law.", "Due to the difficulty of using these methods, they did not realize that the nebulae were actually galaxies outside our own Milky Way, nor did they speculate about the cosmological implications.", "In 1927, the Belgian Roman Catholic priest Georges Lemaître independently derived the Friedmann–Lemaître–Robertson–Walker equations and proposed, on the basis of the recession of spiral nebulae, that the universe began with the \"explosion\" of a \"primeval atom\"—which was later called the Big Bang.", "In 1929, Edwin Hubble provided an observational basis for Lemaître's theory.", "Hubble showed that the spiral nebulae were galaxies by determining their distances using measurements of the brightness of Cepheid variable stars.", "He discovered a relationship between the redshift of a galaxy and its distance.", "He interpreted this as evidence that the galaxies are receding from Earth in every direction at speeds proportional to their distance.", "This fact is now known as Hubble's law, though the numerical factor Hubble found relating recessional velocity and distance was off by a factor of ten, due to not knowing about the types of Cepheid variables.Given the cosmological principle, Hubble's law suggested that the universe was expanding.", "Two primary explanations were proposed for the expansion.", "One was Lemaître's Big Bang theory, advocated and developed by George Gamow.", "The other explanation was Fred Hoyle's steady state model in which new matter is created as the galaxies move away from each other.", "In this model, the universe is roughly the same at any point in time.For a number of years, support for these theories was evenly divided.", "However, the observational evidence began to support the idea that the universe evolved from a hot dense state.", "The discovery of the cosmic microwave background in 1965 lent strong support to the Big Bang model, and since the precise measurements of the cosmic microwave background by the Cosmic Background Explorer in the early 1990s, few cosmologists have seriously proposed other theories of the origin and evolution of the cosmos.", "One consequence of this is that in standard general relativity, the universe began with a singularity, as demonstrated by Roger Penrose and Stephen Hawking in the 1960s.An alternative view to extend the Big Bang model, suggesting the universe had no beginning or singularity and the age of the universe is infinite, has been presented.In September 2023, astrophysicists questioned the overall current view of the universe, in the form of the Standard Model of Cosmology, based on the latest James Webb Space Telescope studies." ], [ "Energy of the cosmos", "The lightest chemical elements, primarily hydrogen and helium, were created during the Big Bang through the process of nucleosynthesis.", "In a sequence of stellar nucleosynthesis reactions, smaller atomic nuclei are then combined into larger atomic nuclei, ultimately forming stable iron group elements such as iron and nickel, which have the highest nuclear binding energies.", "The net process results in a ''later energy release'', meaning subsequent to the Big Bang.", "Such reactions of nuclear particles can lead to ''sudden energy releases'' from cataclysmic variable stars such as novae.", "Gravitational collapse of matter into black holes also powers the most energetic processes, generally seen in the nuclear regions of galaxies, forming ''quasars'' and ''active galaxies''.Cosmologists cannot explain all cosmic phenomena exactly, such as those related to the accelerating expansion of the universe, using conventional forms of energy.", "Instead, cosmologists propose a new form of energy called dark energy that permeates all space.", "One hypothesis is that dark energy is just the vacuum energy, a component of empty space that is associated with the virtual particles that exist due to the uncertainty principle.There is no clear way to define the total energy in the universe using the most widely accepted theory of gravity, general relativity.", "Therefore, it remains controversial whether the total energy is conserved in an expanding universe.", "For instance, each photon that travels through intergalactic space loses energy due to the redshift effect.", "This energy is not transferred to any other system, so seems to be permanently lost.", "On the other hand, some cosmologists insist that energy is conserved in some sense; this follows the law of conservation of energy.Different forms of energy may dominate the cosmos—relativistic particles which are referred to as radiation, or non-relativistic particles referred to as matter.", "Relativistic particles are particles whose rest mass is zero or negligible compared to their kinetic energy, and so move at the speed of light or very close to it; non-relativistic particles have much higher rest mass than their energy and so move much slower than the speed of light.As the universe expands, both matter and radiation become diluted.", "However, the energy densities of radiation and matter dilute at different rates.", "As a particular volume expands, mass-energy density is changed only by the increase in volume, but the energy density of radiation is changed both by the increase in volume and by the increase in the wavelength of the photons that make it up.", "Thus the energy of radiation becomes a smaller part of the universe's total energy than that of matter as it expands.", "The very early universe is said to have been 'radiation dominated' and radiation controlled the deceleration of expansion.", "Later, as the average energy per photon becomes roughly 10 eV and lower, matter dictates the rate of deceleration and the universe is said to be 'matter dominated'.", "The intermediate case is not treated well analytically.", "As the expansion of the universe continues, matter dilutes even further and the cosmological constant becomes dominant, leading to an acceleration in the universe's expansion." ], [ "History of the universe", "The history of the universe is a central issue in cosmology.", "The history of the universe is divided into different periods called epochs, according to the dominant forces and processes in each period.", "The standard cosmological model is known as the Lambda-CDM model.===Equations of motion===Within the standard cosmological model, the equations of motion governing the universe as a whole are derived from general relativity with a small, positive cosmological constant.", "The solution is an expanding universe; due to this expansion, the radiation and matter in the universe cool down and become diluted.", "At first, the expansion is slowed down by gravitation attracting the radiation and matter in the universe.", "However, as these become diluted, the cosmological constant becomes more dominant and the expansion of the universe starts to accelerate rather than decelerate.", "In our universe this happened billions of years ago.===Particle physics in cosmology===During the earliest moments of the universe, the average energy density was very high, making knowledge of particle physics critical to understanding this environment.", "Hence, scattering processes and decay of unstable elementary particles are important for cosmological models of this period.As a rule of thumb, a scattering or a decay process is cosmologically important in a certain epoch if the time scale describing that process is smaller than, or comparable to, the time scale of the expansion of the universe.", "The time scale that describes the expansion of the universe is with being the Hubble parameter, which varies with time.", "The expansion timescale is roughly equal to the age of the universe at each point in time.===Timeline of the Big Bang===Observations suggest that the universe began around 13.8 billion years ago.", "Since then, the evolution of the universe has passed through three phases.", "The very early universe, which is still poorly understood, was the split second in which the universe was so hot that particles had energies higher than those currently accessible in particle accelerators on Earth.", "Therefore, while the basic features of this epoch have been worked out in the Big Bang theory, the details are largely based on educated guesses.Following this, in the early universe, the evolution of the universe proceeded according to known high energy physics.", "This is when the first protons, electrons and neutrons formed, then nuclei and finally atoms.", "With the formation of neutral hydrogen, the cosmic microwave background was emitted.", "Finally, the epoch of structure formation began, when matter started to aggregate into the first stars and quasars, and ultimately galaxies, clusters of galaxies and superclusters formed.", "The future of the universe is not yet firmly known, but according to the ΛCDM model it will continue expanding forever." ], [ "Areas of study", "Below, some of the most active areas of inquiry in cosmology are described, in roughly chronological order.", "This does not include all of the Big Bang cosmology, which is presented in ''Timeline of the Big Bang.", "''===Very early universe===The early, hot universe appears to be well explained by the Big Bang from roughly 10−33 seconds onwards, but there are several problems.", "One is that there is no compelling reason, using current particle physics, for the universe to be flat, homogeneous, and isotropic ''(see the cosmological principle)''.", "Moreover, grand unified theories of particle physics suggest that there should be magnetic monopoles in the universe, which have not been found.", "These problems are resolved by a brief period of cosmic inflation, which drives the universe to flatness, smooths out anisotropies and inhomogeneities to the observed level, and exponentially dilutes the monopoles.", "The physical model behind cosmic inflation is extremely simple, but it has not yet been confirmed by particle physics, and there are difficult problems reconciling inflation and quantum field theory.", "Some cosmologists think that string theory and brane cosmology will provide an alternative to inflation.Another major problem in cosmology is what caused the universe to contain far more matter than antimatter.", "Cosmologists can observationally deduce that the universe is not split into regions of matter and antimatter.", "If it were, there would be X-rays and gamma rays produced as a result of annihilation, but this is not observed.", "Therefore, some process in the early universe must have created a small excess of matter over antimatter, and this (currently not understood) process is called ''baryogenesis''.", "Three required conditions for baryogenesis were derived by Andrei Sakharov in 1967, and requires a violation of the particle physics symmetry, called CP-symmetry, between matter and antimatter.", "However, particle accelerators measure too small a violation of CP-symmetry to account for the baryon asymmetry.", "Cosmologists and particle physicists look for additional violations of the CP-symmetry in the early universe that might account for the baryon asymmetry.Both the problems of baryogenesis and cosmic inflation are very closely related to particle physics, and their resolution might come from high energy theory and experiment, rather than through observations of the universe.===Big Bang Theory===Big Bang nucleosynthesis is the theory of the formation of the elements in the early universe.", "It finished when the universe was about three minutes old and its temperature dropped below that at which nuclear fusion could occur.", "Big Bang nucleosynthesis had a brief period during which it could operate, so only the very lightest elements were produced.", "Starting from hydrogen ions (protons), it principally produced deuterium, helium-4, and lithium.", "Other elements were produced in only trace abundances.", "The basic theory of nucleosynthesis was developed in 1948 by George Gamow, Ralph Asher Alpher, and Robert Herman.", "It was used for many years as a probe of physics at the time of the Big Bang, as the theory of Big Bang nucleosynthesis connects the abundances of primordial light elements with the features of the early universe.", "Specifically, it can be used to test the equivalence principle, to probe dark matter, and test neutrino physics.", "Some cosmologists have proposed that Big Bang nucleosynthesis suggests there is a fourth \"sterile\" species of neutrino.====Standard model of Big Bang cosmology====The '''ΛCDM''' ('''Lambda cold dark matter''') or '''Lambda-CDM''' model is a parametrization of the Big Bang cosmological model in which the universe contains a cosmological constant, denoted by Lambda (Greek '''Λ'''), associated with dark energy, and cold dark matter (abbreviated '''CDM''').", "It is frequently referred to as the '''standard model''' of Big Bang cosmology.===Cosmic microwave background===The cosmic microwave background is radiation left over from decoupling after the epoch of recombination when neutral atoms first formed.", "At this point, radiation produced in the Big Bang stopped Thomson scattering from charged ions.", "The radiation, first observed in 1965 by Arno Penzias and Robert Woodrow Wilson, has a perfect thermal black-body spectrum.", "It has a temperature of 2.7 kelvins today and is isotropic to one part in 105.Cosmological perturbation theory, which describes the evolution of slight inhomogeneities in the early universe, has allowed cosmologists to precisely calculate the angular power spectrum of the radiation, and it has been measured by the recent satellite experiments (COBE and WMAP) and many ground and balloon-based experiments (such as Degree Angular Scale Interferometer, Cosmic Background Imager, and Boomerang).", "One of the goals of these efforts is to measure the basic parameters of the Lambda-CDM model with increasing accuracy, as well as to test the predictions of the Big Bang model and look for new physics.", "The results of measurements made by WMAP, for example, have placed limits on the neutrino masses.Newer experiments, such as QUIET and the Atacama Cosmology Telescope, are trying to measure the polarization of the cosmic microwave background.", "These measurements are expected to provide further confirmation of the theory as well as information about cosmic inflation, and the so-called secondary anisotropies, such as the Sunyaev-Zel'dovich effect and Sachs-Wolfe effect, which are caused by interaction between galaxies and clusters with the cosmic microwave background.On 17 March 2014, astronomers of the BICEP2 Collaboration announced the apparent detection of ''B''-mode polarization of the CMB, considered to be evidence of primordial gravitational waves that are predicted by the theory of inflation to occur during the earliest phase of the Big Bang.", "However, later that year the Planck collaboration provided a more accurate measurement of cosmic dust, concluding that the B-mode signal from dust is the same strength as that reported from BICEP2.On 30 January 2015, a joint analysis of BICEP2 and Planck data was published and the European Space Agency announced that the signal can be entirely attributed to interstellar dust in the Milky Way.===Formation and evolution of large-scale structure===Understanding the formation and evolution of the largest and earliest structures (i.e., quasars, galaxies, clusters and superclusters) is one of the largest efforts in cosmology.", "Cosmologists study a model of '''hierarchical structure formation''' in which structures form from the bottom up, with smaller objects forming first, while the largest objects, such as superclusters, are still assembling.", "One way to study structure in the universe is to survey the visible galaxies, in order to construct a three-dimensional picture of the galaxies in the universe and measure the matter power spectrum.", "This is the approach of the ''Sloan Digital Sky Survey'' and the 2dF Galaxy Redshift Survey.Another tool for understanding structure formation is simulations, which cosmologists use to study the gravitational aggregation of matter in the universe, as it clusters into filaments, superclusters and voids.", "Most simulations contain only non-baryonic cold dark matter, which should suffice to understand the universe on the largest scales, as there is much more dark matter in the universe than visible, baryonic matter.", "More advanced simulations are starting to include baryons and study the formation of individual galaxies.", "Cosmologists study these simulations to see if they agree with the galaxy surveys, and to understand any discrepancy.Other, complementary observations to measure the distribution of matter in the distant universe and to probe reionization include:* The Lyman-alpha forest, which allows cosmologists to measure the distribution of neutral atomic hydrogen gas in the early universe, by measuring the absorption of light from distant quasars by the gas.", "* The 21-centimeter absorption line of neutral atomic hydrogen also provides a sensitive test of cosmology.", "* Weak lensing, the distortion of a distant image by gravitational lensing due to dark matter.These will help cosmologists settle the question of when and how structure formed in the universe.===Dark matter===Evidence from Big Bang nucleosynthesis, the cosmic microwave background, structure formation, and galaxy rotation curves suggests that about 23% of the mass of the universe consists of non-baryonic dark matter, whereas only 4% consists of visible, baryonic matter.", "The gravitational effects of dark matter are well understood, as it behaves like a cold, non-radiative fluid that forms haloes around galaxies.", "Dark matter has never been detected in the laboratory, and the particle physics nature of dark matter remains completely unknown.", "Without observational constraints, there are a number of candidates, such as a stable supersymmetric particle, a weakly interacting massive particle, a gravitationally-interacting massive particle, an axion, and a massive compact halo object.", "Alternatives to the dark matter hypothesis include a modification of gravity at small accelerations (MOND) or an effect from brane cosmology.", "TeVeS is a version of MOND that can explain gravitational lensing.===Dark energy===If the universe is flat, there must be an additional component making up 73% (in addition to the 23% dark matter and 4% baryons) of the energy density of the universe.", "This is called dark energy.", "In order not to interfere with Big Bang nucleosynthesis and the cosmic microwave background, it must not cluster in haloes like baryons and dark matter.", "There is strong observational evidence for dark energy, as the total energy density of the universe is known through constraints on the flatness of the universe, but the amount of clustering matter is tightly measured, and is much less than this.", "The case for dark energy was strengthened in 1999, when measurements demonstrated that the expansion of the universe has begun to gradually accelerate.Apart from its density and its clustering properties, nothing is known about dark energy.", "''Quantum field theory'' predicts a cosmological constant (CC) much like dark energy, but 120 orders of magnitude larger than that observed.", "Steven Weinberg and a number of string theorists ''(see string landscape)'' have invoked the 'weak anthropic principle': i.e.", "the reason that physicists observe a universe with such a small cosmological constant is that no physicists (or any life) could exist in a universe with a larger cosmological constant.", "Many cosmologists find this an unsatisfying explanation: perhaps because while the weak anthropic principle is self-evident (given that living observers exist, there must be at least one universe with a cosmological constant which allows for life to exist) it does not attempt to explain the context of that universe.", "For example, the weak anthropic principle alone does not distinguish between:* Only one universe will ever exist and there is some underlying principle that constrains the CC to the value we observe.", "* Only one universe will ever exist and although there is no underlying principle fixing the CC, we got lucky.", "* Lots of universes exist (simultaneously or serially) with a range of CC values, and of course ours is one of the life-supporting ones.Other possible explanations for dark energy include quintessence or a modification of gravity on the largest scales.", "The effect on cosmology of the dark energy that these models describe is given by the dark energy's equation of state, which varies depending upon the theory.", "The nature of dark energy is one of the most challenging problems in cosmology.A better understanding of dark energy is likely to solve the problem of the ultimate fate of the universe.", "In the current cosmological epoch, the accelerated expansion due to dark energy is preventing structures larger than superclusters from forming.", "It is not known whether the acceleration will continue indefinitely, perhaps even increasing until a big rip, or whether it will eventually reverse, lead to a Big Freeze, or follow some other scenario.===Gravitational waves===Gravitational waves are ripples in the curvature of spacetime that propagate as waves at the speed of light, generated in certain gravitational interactions that propagate outward from their source.", "Gravitational-wave astronomy is an emerging branch of observational astronomy which aims to use gravitational waves to collect observational data about sources of detectable gravitational waves such as binary star systems composed of white dwarfs, neutron stars, and black holes; and events such as supernovae, and the formation of the early universe shortly after the Big Bang.In 2016, the LIGO Scientific Collaboration and Virgo Collaboration teams announced that they had made the first observation of gravitational waves, originating from a pair of merging black holes using the Advanced LIGO detectors.", "On 15 June 2016, a second detection of gravitational waves from coalescing black holes was announced.", "Besides LIGO, many other gravitational-wave observatories (detectors) are under construction.===Other areas of inquiry===Cosmologists also study:* Whether primordial black holes were formed in our universe, and what happened to them.", "* Detection of cosmic rays with energies above the GZK cutoff, and whether it signals a failure of special relativity at high energies.", "* The equivalence principle, whether or not Einstein's general theory of relativity is the correct theory of gravitation, and if the fundamental laws of physics are the same everywhere in the universe." ], [ "See also", "* Accretion* Hubble's law* Illustris project* List of cosmologists* Physical ontology* Quantum cosmology* String cosmology* Universal Rotation Curve" ], [ "References" ], [ "Further reading", "===Popular===* * * * * * * ===Textbooks===* Introductory cosmology and general relativity without the full tensor apparatus, deferred until the last part of the book.", "* Modern introduction to cosmology covering the homogeneous and inhomogeneous universe as well as inflation and the CMB.", "* An introductory text, released slightly before the WMAP results.", "* * * For undergraduates; mathematically gentle with a strong historical focus.", "* An introductory astronomy text.", "* The classic reference for researchers.", "* Cosmology without general relativity.", "* An introduction to cosmology with a thorough discussion of inflation.", "* * Discusses the formation of large-scale structures in detail.", "* An introduction including more on general relativity and quantum field theory than most.", "* Strong historical focus.", "* The classic work on large-scale structure and correlation functions.", "* * A standard reference for the mathematical formalism.", "*" ], [ "External links", "===From groups===* Cambridge Cosmology – from Cambridge University (public home page)* Cosmology 101 – from the NASA WMAP group* Center for Cosmological Physics.", "University of Chicago, Chicago.", "* Origins, Nova Online – Provided by ''PBS''.===From individuals===* Gale, George, \" Cosmology: Methodological Debates in the 1930s and 1940s\", ''The Stanford Encyclopedia of Philosophy'', Edward N. Zalta (ed.", ")* Madore, Barry F., \"'' Level 5 : A Knowledgebase for Extragalactic Astronomy and Cosmology''\".", "Caltech and Carnegie.", "Pasadena, California.", "* Tyler, Pat, and Phil Newman \"'' Beyond Einstein''\".", "Laboratory for High Energy Astrophysics (LHEA) NASA Goddard Space Flight Center.", "* Wright, Ned. \"''", "Cosmology tutorial and FAQ''\".", "Division of Astronomy & Astrophysics, UCLA.", "* *" ] ]

[ [ "Inflation (cosmology)" ], [ "Introduction", " In physical cosmology, '''cosmic inflation''', '''cosmological inflation''', or just '''inflation''', is a theory of exponential expansion of space in the early universe.", "The inflationary epoch is believed to have lasted from  seconds to between and  seconds after the Big Bang.", "Following the inflationary period, the universe continued to expand, but at a slower rate.", "The acceleration of this expansion due to dark energy began after the universe was already over 7.7 billion years old (5.4 billion years ago).Inflation theory was developed in the late 1970s and early 80s, with notable contributions by several theoretical physicists, including Alexei Starobinsky at Landau Institute for Theoretical Physics, Alan Guth at Cornell University, and Andrei Linde at Lebedev Physical Institute.", "Alexei Starobinsky, Alan Guth, and Andrei Linde won the 2014 Kavli Prize \"for pioneering the theory of cosmic inflation\".", "It was developed further in the early 1980s.", "It explains the origin of the large-scale structure of the cosmos.", "Quantum fluctuations in the microscopic inflationary region, magnified to cosmic size, become the seeds for the growth of structure in the Universe (see galaxy formation and evolution and structure formation).", "Many physicists also believe that inflation explains why the universe appears to be the same in all directions (isotropic), why the cosmic microwave background radiation is distributed evenly, why the universe is flat, and why no magnetic monopoles have been observed.The detailed particle physics mechanism responsible for inflation is unknown.", "The basic inflationary paradigm is accepted by most physicists, as a number of inflation model predictions have been confirmed by observation; however, a substantial minority of scientists dissent from this position.", "The hypothetical field thought to be responsible for inflation is called the inflaton.In 2002 three of the original architects of the theory were recognized for their major contributions; physicists Alan Guth of M.I.T., Andrei Linde of Stanford, and Paul Steinhardt of Princeton shared the prestigious Dirac Prize \"for development of the concept of inflation in cosmology\".", "In 2012 Guth and Linde were awarded the Breakthrough Prize in Fundamental Physics for their invention and development of inflationary cosmology." ], [ "Overview", "Around 1930, Edwin Hubble discovered that light from remote galaxies was redshifted; the more remote, the more shifted.", "This implies that the galaxies are receding from the Earth, with more distant galaxies receding more rapidly, such that galaxies also recede from each other.", "This expansion of the universe was previously predicted by Alexander Friedmann and Georges Lemaître from the theory of general relativity.", "It can be understood as a consequence of an initial impulse, which sent the contents of the universe flying apart at such a rate that their mutual gravitational attraction has not reversed their separation.Inflation may provide this initial impulse.", "According to the Friedmann equations that describe the dynamics of an expanding universe, a fluid with sufficiently negative pressure exerts gravitational repulsion in the cosmological context.", "A field in a positive-energy false vacuum state could represent such a fluid, and the resulting repulsion would set the universe into exponential expansion.", "This ''inflation'' phase was originally proposed by Alan Guth in 1979 because the exponential expansion could dilute exotic relics, such as magnetic monopoles, that were predicted by grand unified theories at the time.", "This would explain why such relics were not seen.", "It was quickly realized that such accelerated expansion would resolve the horizon problem and the flatness problem.", "These problems arise from the notion that to look like it does ''today'', the Universe must have started from very finely tuned, or \"special\", initial conditions at the Big Bang." ], [ "Theory", "An expanding universe generally has a cosmological horizon, which, by analogy with the more familiar horizon caused by the curvature of Earth's surface, marks the boundary of the part of the Universe that an observer can see.", "Light (or other radiation) emitted by objects beyond the cosmological horizon in an accelerating universe never reaches the observer, because the space in between the observer and the object is expanding too rapidly.History of the Universe – gravitational waves are hypothesized to arise from cosmic inflation, a phase of accelerated expansion just after the Big Bang.The observable universe is one ''causal patch'' of a much larger unobservable universe; other parts of the Universe cannot communicate with Earth yet.", "These parts of the Universe are outside our current cosmological horizon.", "In the standard hot big bang model, without inflation, the cosmological horizon moves out, bringing new regions into view.", "Yet as a local observer sees such a region for the first time, it looks no different from any other region of space the local observer has already seen: its background radiation is at nearly the same temperature as the background radiation of other regions, and its space-time curvature is evolving lock-step with the others.", "This presents a mystery: how did these new regions know what temperature and curvature they were supposed to have?", "They couldn't have learned it by getting signals, because they were not previously in communication with our past light cone.Inflation answers this question by postulating that all the regions come from an earlier era with a big vacuum energy, or cosmological constant.", "A space with a cosmological constant is qualitatively different: instead of moving outward, the cosmological horizon stays put.", "For any one observer, the distance to the cosmological horizon is constant.", "With exponentially expanding space, two nearby observers are separated very quickly; so much so, that the distance between them quickly exceeds the limits of communication.", "The spatial slices are expanding very fast to cover huge volumes.", "Things are constantly moving beyond the cosmological horizon, which is a fixed distance away, and everything becomes homogeneous.As the inflationary field slowly relaxes to the vacuum, the cosmological constant goes to zero and space begins to expand normally.", "The new regions that come into view during the normal expansion phase are exactly the same regions that were pushed out of the horizon during inflation, and so they are at nearly the same temperature and curvature, because they come from the same originally small patch of space.The theory of inflation thus explains why the temperatures and curvatures of different regions are so nearly equal.", "It also predicts that the total curvature of a space-slice at constant global time is zero.", "This prediction implies that the total ordinary matter, dark matter and residual vacuum energy in the Universe have to add up to the critical density, and the evidence supports this.", "More strikingly, inflation allows physicists to calculate the minute differences in temperature of different regions from quantum fluctuations during the inflationary era, and many of these quantitative predictions have been confirmed.===Space expands===In a space that expands exponentially (or nearly exponentially) with time, any pair of free-floating objects that are initially at rest will move apart from each other at an accelerating rate, at least as long as they are not bound together by any force.", "From the point of view of one such object, the spacetime is something like an inside-out Schwarzschild black hole—each object is surrounded by a spherical event horizon.", "Once the other object has fallen through this horizon it can never return, and even light signals it sends will never reach the first object (at least so long as the space continues to expand exponentially).In the approximation that the expansion is exactly exponential, the horizon is static and remains a fixed physical distance away.", "This patch of an inflating universe can be described by the following metric::This exponentially expanding spacetime is called a de Sitter space, and to sustain it there must be a cosmological constant, a vacuum energy density that is constant in space and time and proportional to Λ in the above metric.", "For the case of exactly exponential expansion, the vacuum energy has a negative pressure ''p'' equal in magnitude to its energy density ''ρ''; the equation of state is ''p=−ρ''.Inflation is typically not an exactly exponential expansion, but rather quasi- or near-exponential.", "In such a universe the horizon will slowly grow with time as the vacuum energy density gradually decreases.===Few inhomogeneities remain===Because the accelerating expansion of space stretches out any initial variations in density or temperature to very large length scales, an essential feature of inflation is that it smooths out inhomogeneities and anisotropies, and reduces the curvature of space.", "This pushes the Universe into a very simple state in which it is completely dominated by the inflaton field and the only significant inhomogeneities are tiny quantum fluctuations.", "Inflation also dilutes exotic heavy particles, such as the magnetic monopoles predicted by many extensions to the Standard Model of particle physics.", "If the Universe was only hot enough to form such particles ''before'' a period of inflation, they would not be observed in nature, as they would be so rare that it is quite likely that there are none in the observable universe.", "Together, these effects are called the inflationary \"no-hair theorem\" by analogy with the no hair theorem for black holes.The \"no-hair\" theorem works essentially because the cosmological horizon is no different from a black-hole horizon, except for not testable disagreements about what is on the other side.", "The interpretation of the no-hair theorem is that the Universe (observable and unobservable) expands by an enormous factor during inflation.", "In an expanding universe, energy densities generally fall, or get diluted, as the volume of the Universe increases.", "For example, the density of ordinary \"cold\" matter (dust) goes down as the inverse of the volume: when linear dimensions double, the energy density goes down by a factor of eight; the radiation energy density goes down even more rapidly as the Universe expands since the wavelength of each photon is stretched (redshifted), in addition to the photons being dispersed by the expansion.", "When linear dimensions are doubled, the energy density in radiation falls by a factor of sixteen (see the solution of the energy density continuity equation for an ultra-relativistic fluid).", "During inflation, the energy density in the inflaton field is roughly constant.", "However, the energy density in everything else, including inhomogeneities, curvature, anisotropies, exotic particles, and standard-model particles is falling, and through sufficient inflation these all become negligible.", "This leaves the Universe flat and symmetric, and (apart from the homogeneous inflaton field) mostly empty, at the moment inflation ends and reheating begins.===Duration===A key requirement is that inflation must continue long enough to produce the present observable universe from a single, small inflationary Hubble volume.", "This is necessary to ensure that the Universe appears flat, homogeneous and isotropic at the largest observable scales.", "This requirement is generally thought to be satisfied if the Universe expanded by a factor of at least during inflation.===Reheating===Inflation is a period of supercooled expansion, when the temperature drops by a factor of 100,000 or so.", "(The exact drop is model-dependent, but in the first models it was typically from  K down to  K.) This relatively low temperature is maintained during the inflationary phase.", "When inflation ends the temperature returns to the pre-inflationary temperature; this is called ''reheating'' or thermalization because the large potential energy of the inflaton field decays into particles and fills the Universe with Standard Model particles, including electromagnetic radiation, starting the radiation dominated phase of the Universe.", "Because the nature of the inflaton field is not known, this process is still poorly understood, although it is believed to take place through a parametric resonance." ], [ "Motivations", "Inflation resolves several problems in Big Bang cosmology that were discovered in the 1970s.", "Inflation was first proposed by Alan Guth in 1979 while investigating the problem of why no magnetic monopoles are seen today; he found that a positive-energy false vacuum would, according to general relativity, generate an exponential expansion of space.", "It was very quickly realised that such an expansion would resolve many other long-standing problems.", "These problems arise from the observation that to look like it does ''today'', the Universe would have to have started from very finely tuned, or \"special\" initial conditions at the Big Bang.", "Inflation attempts to resolve these problems by providing a dynamical mechanism that drives the Universe to this special state, thus making a universe like ours much more likely in the context of the Big Bang theory.===Horizon problem===The horizon problem is the problem of determining why the universe appears statistically homogeneous and isotropic in accordance with the cosmological principle.", "For example, molecules in a canister of gas are distributed homogeneously and isotropically because they are in thermal equilibrium: gas throughout the canister has had enough time to interact to dissipate inhomogeneities and anisotropies.", "The situation is quite different in the big bang model without inflation, because gravitational expansion does not give the early universe enough time to equilibrate.", "In a big bang with only the matter and radiation known in the Standard Model, two widely separated regions of the observable universe cannot have equilibrated because they move apart from each other faster than the speed of light and thus have never come into causal contact.", "In the early Universe, it was not possible to send a light signal between the two regions.", "Because they have had no interaction, it is difficult to explain why they have the same temperature (are thermally equilibrated).", "Historically, proposed solutions included the ''Phoenix universe'' of Georges Lemaître, the related oscillatory universe of Richard Chase Tolman, and the Mixmaster universe of Charles Misner.", "Lemaître and Tolman proposed that a universe undergoing a number of cycles of contraction and expansion could come into thermal equilibrium.", "Their models failed, however, because of the buildup of entropy over several cycles.", "Misner made the (ultimately incorrect) conjecture that the Mixmaster mechanism, which made the Universe ''more'' chaotic, could lead to statistical homogeneity and isotropy.===Flatness problem===The flatness problem is sometimes called one of the Dicke coincidences (along with the cosmological constant problem).It became known in the 1960s that the density of matter in the Universe was comparable to the critical density necessary for a flat universe (that is, a universe whose large scale geometry is the usual Euclidean geometry, rather than a non-Euclidean hyperbolic or spherical geometry).Therefore, regardless of the shape of the universe the contribution of spatial curvature to the expansion of the Universe could not be much greater than the contribution of matter.", "But as the Universe expands, the curvature redshifts away more slowly than matter and radiation.", "Extrapolated into the past, this presents a fine-tuning problem because the contribution of curvature to the Universe must be exponentially small (sixteen orders of magnitude less than the density of radiation at Big Bang nucleosynthesis, for example).", "This problem is exacerbated by recent observations of the cosmic microwave background that have demonstrated that the Universe is flat to within a few percent.===Magnetic-monopole problem===The magnetic monopole problem, sometimes called \"the exotic-relics problem\", says that if the early universe were very hot, a large number of very heavy, stable magnetic monopoles would have been produced.Stable magnetic monopoles are a problem for Grand Unified Theories, which propose that at high temperatures (such as in the early universe) the electromagnetic force, strong, and weak nuclear forces are not actually fundamental forces but arise due to spontaneous symmetry breaking from a single gauge theory.These theories predict a number of heavy, stable particles that have not been observed in nature.", "The most notorious is the magnetic monopole, a kind of stable, heavy \"charge\" of magnetic field.Monopoles are predicted to be copiously produced following Grand Unified Theories at high temperature,and they should have persisted to the present day, to such an extent that they would become the primary constituent of the Universe.Not only is that not the case, but all searches for them have failed, placing stringent limits on the density of relic magnetic monopoles in the Universe.A period of inflation that occurs below the temperature where magnetic monopoles can be produced would offer a possible resolution of this problem: Monopoles would be separated from each other as the Universe around them expands, potentially lowering their observed density by many orders of magnitude.", "Though, as cosmologist Martin Rees has written,: \"Skeptics about exotic physics might not be hugely impressed by a theoretical argument to explain the absence of particles that are themselves only hypothetical.", "Preventive medicine can readily seem 100 percent effective against a disease that doesn't exist!\"" ], [ "History", "===Precursors===In the early days of General Relativity, Albert Einstein introduced the cosmological constant to allow a static solution, which was a three-dimensional sphere with a uniform density of matter.", "Later, Willem de Sitter found a highly symmetric inflating universe, which described a universe with a cosmological constant that is otherwise empty.It was discovered that Einstein's universe is unstable, and that small fluctuations cause it to collapse or turn into a de Sitter universe.In 1965, Erast Gliner proposed a unique assumption regarding the early Universe's pressure in the context of the Einstein-Friedmann equations.", "According to his idea, the pressure was negatively proportional to the energy density.", "This relationship between pressure and energy density served as the initial theoretical prediction of dark energy.In the early 1970s, Zeldovich noticed the flatness and horizon problems of Big Bang cosmology; before his work, cosmology was presumed to be symmetrical on purely philosophical grounds.", "In the Soviet Union, this and other considerations led Belinski and Khalatnikov to analyze the chaotic BKL singularity in General Relativity.", "Misner's Mixmaster universe attempted to use this chaotic behavior to solve the cosmological problems, with limited success.====False vacuum====In the late 1970s, Sidney Coleman applied the instanton techniques developed by Alexander Polyakov and collaborators to study the fate of the false vacuum in quantum field theory.", "Like a metastable phase in statistical mechanics—water below the freezing temperature or above the boiling point—a quantum field would need to nucleate a large enough bubble of the new vacuum, the new phase, in order to make a transition.", "Coleman found the most likely decay pathway for vacuum decay and calculated the inverse lifetime per unit volume.", "He eventually noted that gravitational effects would be significant, but he did not calculate these effects and did not apply the results to cosmology.The universe could have been spontaneously created from nothing (no space, time, nor matter) by quantum fluctuations of metastable false vacuum causing an expanding bubble of true vacuum.====Starobinsky inflation====In the Soviet Union, Alexei Starobinsky noted that quantum corrections to general relativity should be important for the early universe.", "These generically lead to curvature-squared corrections to the Einstein–Hilbert action and a form of ''f''(''R'') modified gravity.", "The solution to Einstein's equations in the presence of curvature squared terms, when the curvatures are large, leads to an effective cosmological constant.", "Therefore, he proposed that the early universe went through an inflationary de Sitter era.This resolved the cosmology problems and led to specific predictions for the corrections to the microwave background radiation, corrections that were then calculated in detail.", "Starobinsky used the action :which corresponds to the potential:in the Einstein frame.", "This results in the observables:====Monopole problem====In 1978, Zeldovich noted the magnetic monopole problem, which was an unambiguous quantitative version of the horizon problem, this time in a subfield of particle physics, which led to several speculative attempts to resolve it.", "In 1980 Alan Guth realized that false vacuum decay in the early universe would solve the problem, leading him to propose a scalar-driven inflation.", "Starobinsky's and Guth's scenarios both predicted an initial de Sitter phase, differing only in mechanistic details.===Early inflationary models===The physical size of the Hubble radius (solid line) as a function of the linear expansion (scale factor) of the universe.", "During cosmological inflation, the Hubble radius is constant.", "The physical wavelength of a perturbation mode (dashed line) is also shown.", "The plot illustrates how the perturbation mode grows larger than the horizon during cosmological inflation before coming back inside the horizon, which grows rapidly during radiation domination.", "If cosmological inflation had never happened, and radiation domination continued back until a gravitational singularity, then the mode would never have been inside the horizon in the very early universe, and no causal mechanism could have ensured that the universe was homogeneous on the scale of the perturbation mode.Guth proposed inflation in January 1981 to explain the nonexistence of magnetic monopoles;it was Guth who coined the term \"inflation\".", "At the same time, Starobinsky argued that quantum corrections to gravity would replace the supposed initial singularity of the Universe with an exponentially expanding de Sitter phase.In October 1980, Demosthenes Kazanas suggested that exponential expansion could eliminate the particle horizon and perhaps solve the horizon problem,while Sato suggested that an exponential expansion could eliminate domain walls (another kind of exotic relic).", "In 1981 Einhorn and Sato published a model similar to Guth's and showed that it would resolve the puzzle of the magnetic monopole abundance in Grand Unified Theories.", "Like Guth, they concluded that such a model not only required fine tuning of the cosmological constant, but also would likely lead to a much too granular universe, i.e., to large density variations resulting from bubble wall collisions.Guth proposed that as the early universe cooled, it was trapped in a false vacuum with a high energy density, which is much like a cosmological constant.", "As the very early universe cooled it was trapped in a metastable state (it was supercooled), which it could only decay out of through the process of bubble nucleation via quantum tunneling.", "Bubbles of true vacuum spontaneously form in the sea of false vacuum and rapidly begin expanding at the speed of light.", "Guth recognized that this model was problematic because the model did not reheat properly: when the bubbles nucleated, they did not generate any radiation.", "Radiation could only be generated in collisions between bubble walls.", "But if inflation lasted long enough to solve the initial conditions problems, collisions between bubbles became exceedingly rare.", "In any one causal patch it is likely that only one bubble would nucleate.===Slow-roll inflation===The bubble collision problem was solved by Linde and independently by Andreas Albrecht and Paul Steinhardt in a model named ''new inflation'' or ''slow-roll inflation'' (Guth's model then became known as ''old inflation'').", "In this model, instead of tunneling out of a false vacuum state, inflation occurred by a scalar field rolling down a potential energy hill.", "When the field rolls very slowly compared to the expansion of the Universe, inflation occurs.", "However, when the hill becomes steeper, inflation ends and reheating can occur.===Effects of asymmetries===Eventually, it was shown that new inflation does not produce a perfectly symmetric universe, but that quantum fluctuations in the inflaton are created.", "These fluctuations form the primordial seeds for all structure created in the later universe.", "These fluctuations were first calculated by Viatcheslav Mukhanov and G. V. Chibisov in analyzing Starobinsky's similar model.", "In the context of inflation, they were worked out independently of the work of Mukhanov and Chibisov at the three-week 1982 Nuffield Workshop on the Very Early Universe at Cambridge University.", "The fluctuations were calculated by four groups working separately over the course of the workshop: Stephen Hawking; Starobinsky; Guth and So-Young Pi; and Bardeen, Steinhardt and Turner." ], [ "Observational status", "Inflation is a mechanism for realizing the cosmological principle, which is the basis of the standard model of physical cosmology: it accounts for the homogeneity and isotropy of the observable universe.", "In addition, it accounts for the observed flatness and absence of magnetic monopoles.", "Since Guth's early work, each of these observations has received further confirmation, most impressively by the detailed observations of the cosmic microwave background made by the Planck spacecraft.", "This analysis shows that the Universe is flat to within percent, and that it is homogeneous and isotropic to one part in 100,000.Inflation predicts that the structures visible in the Universe today formed through the gravitational collapse of perturbations that were formed as quantum mechanical fluctuations in the inflationary epoch.", "The detailed form of the spectrum of perturbations, called a nearly-scale-invariant Gaussian random field is very specific and has only two free parameters.", "One is the amplitude of the spectrum and the ''spectral index'', which measures the slight deviation from scale invariance predicted by inflation (perfect scale invariance corresponds to the idealized de Sitter universe).The other free parameter is the tensor to scalar ratio.", "The simplest inflation models, those without fine-tuning, predict a tensor to scalar ratio near 0.1 .Inflation predicts that the observed perturbations should be in thermal equilibrium with each other (these are called ''adiabatic'' or ''isentropic'' perturbations).", "This structure for the perturbations has been confirmed by the Planck spacecraft, WMAP spacecraft and other cosmic microwave background (CMB) experiments, and galaxy surveys, especially the ongoing Sloan Digital Sky Survey.", "These experiments have shown that the one part in 100,000 inhomogeneities observed have exactly the form predicted by theory.", "There is evidence for a slight deviation from scale invariance.", "The ''spectral index'', is one for a scale-invariant Harrison–Zel'dovich spectrum.", "The simplest inflation models predict that is between 0.92 and 0.98 .", "This is the range that is possible without fine-tuning of the parameters related to energy.", "From Planck data it can be inferred that =0.968 ± 0.006, and a tensor to scalar ratio that is less than 0.11 .", "These are considered an important confirmation of the theory of inflation.Various inflation theories have been proposed that make radically different predictions, but they generally have much more fine-tuning than should be necessary.", "As a physical model, however, inflation is most valuable in that it robustly predicts the initial conditions of the Universe based on only two adjustable parameters: the spectral index (that can only change in a small range) and the amplitude of the perturbations.", "Except in contrived models, this is true regardless of how inflation is realized in particle physics.Occasionally, effects are observed that appear to contradict the simplest models of inflation.", "The first-year WMAP data suggested that the spectrum might not be nearly scale-invariant, but might instead have a slight curvature.", "However, the third-year data revealed that the effect was a statistical anomaly.", "Another effect remarked upon since the first cosmic microwave background satellite, the Cosmic Background Explorer is that the amplitude of the quadrupole moment of the CMB is unexpectedly low and the other low multipoles appear to be preferentially aligned with the ecliptic plane.", "Some have claimed that this is a signature of non-Gaussianity and thus contradicts the simplest models of inflation.", "Others have suggested that the effect may be due to other new physics, foreground contamination, or even publication bias.An experimental program is underway to further test inflation with more precise CMB measurements.", "In particular, high precision measurements of the so-called \"B-modes\" of the polarization of the background radiation could provide evidence of the gravitational radiation produced by inflation, and could also show whether the energy scale of inflation predicted by the simplest models (~ GeV) is correct.", "In March 2014, the BICEP2 team announced B-mode CMB polarization confirming inflation had been demonstrated.", "The team announced the tensor-to-scalar power ratio was between 0.15 and 0.27 (rejecting the null hypothesis; is expected to be 0 in the absence of inflation).", "However, on 19 June 2014, lowered confidence in confirming the findings was reported; on 19 September 2014, a further reduction in confidence was reported and, on 30 January 2015, even less confidence yet was reported.", "By 2018, additional data suggested, with 95% confidence, that is 0.06 or lower: consistent with the null hypothesis, but still also consistent with many remaining models of inflation.Other potentially corroborating measurements are expected from the Planck spacecraft, although it is unclear if the signal will be visible, or if contamination from foreground sources will interfere.", "Other forthcoming measurements, such as those of 21 centimeter radiation (radiation emitted and absorbed from neutral hydrogen before the first stars formed), may measure the power spectrum with even greater resolution than the CMB and galaxy surveys, although it is not known if these measurements will be possible or if interference with radio sources on Earth and in the galaxy will be too great." ], [ "Theoretical status", "In Guth's early proposal, it was thought that the inflaton was the Higgs field, the field that explains the mass of the elementary particles.", "It is now believed by some that the inflaton cannot be the Higgs fieldalthough the recent discovery of the Higgs boson has increased the number of works considering the Higgs field as inflaton.One problem of this identification is the current tension with experimental data at the electroweak scale, which is currently under study at the Large Hadron Collider (LHC).", "Other models of inflation relied on the properties of Grand Unified Theories.", "Since the simplest models of grand unification have failed, it is now thought by many physicists that inflation will be included in a supersymmetric theory such as string theory or a supersymmetric grand unified theory.", "At present, while inflation is understood principally by its detailed predictions of the initial conditions for the hot early universe, the particle physics is largely ''ad hoc'' modelling.", "As such, although predictions of inflation have been consistent with the results of observational tests, many open questions remain.===Fine-tuning problem===One of the most severe challenges for inflation arises from the need for fine tuning.", "In new inflation, the ''slow-roll conditions'' must be satisfied for inflation to occur.", "The slow-roll conditions say that the inflaton potential must be flat (compared to the large vacuum energy) and that the inflaton particles must have a small mass.", "New inflation requires the Universe to have a scalar field with an especially flat potential and special initial conditions.", "However, explanations for these fine-tunings have been proposed.", "For example, classically scale invariant field theories, where scale invariance is broken by quantum effects, provide an explanation of the flatness of inflationary potentials, as long as the theory can be studied through perturbation theory.Linde proposed a theory known as ''chaotic inflation'' in which he suggested that the conditions for inflation were actually satisfied quite generically.", "Inflation will occur in virtually any universe that begins in a chaotic, high energy state that has a scalar field with unbounded potential energy.", "However, in his model the inflaton field necessarily takes values larger than one Planck unit: for this reason, these are often called ''large field'' models and the competing new inflation models are called ''small field'' models.", "In this situation, the predictions of effective field theory are thought to be invalid, as renormalization should cause large corrections that could prevent inflation.This problem has not yet been resolved and some cosmologists argue that the small field models, in which inflation can occur at a much lower energy scale, are better models.", "While inflation depends on quantum field theory (and the semiclassical approximation to quantum gravity) in an important way, it has not been completely reconciled with these theories.Brandenberger commented on fine-tuning in another situation.", "The amplitude of the primordial inhomogeneities produced in inflation is directly tied to the energy scale of inflation.", "This scale is suggested to be around GeV or times the Planck energy.", "The natural scale is naïvely the Planck scale so this small value could be seen as another form of fine-tuning (called a hierarchy problem): the energy density given by the scalar potential is down by compared to the Planck density.", "This is not usually considered to be a critical problem, however, because the scale of inflation corresponds naturally to the scale of gauge unification.===Eternal inflation===In many models, the inflationary phase of the Universe's expansion lasts forever in at least some regions of the Universe.", "This occurs because inflating regions expand very rapidly, reproducing themselves.", "Unless the rate of decay to the non-inflating phase is sufficiently fast, new inflating regions are produced more rapidly than non-inflating regions.", "In such models, most of the volume of the Universe is continuously inflating at any given time.All models of eternal inflation produce an infinite, hypothetical multiverse, typically a fractal.", "The multiverse theory has created significant dissension in the scientific community about the viability of the inflationary model.Paul Steinhardt, one of the original architects of the inflationary model, introduced the first example of eternal inflation in 1983.He showed that the inflation could proceed forever by producing bubbles of non-inflating space filled with hot matter and radiation surrounded by empty space that continues to inflate.", "The bubbles could not grow fast enough to keep up with the inflation.", "Later that same year, Alexander Vilenkin showed that eternal inflation is generic.Although new inflation is classically rolling down the potential, quantum fluctuations can sometimes lift it to previous levels.", "These regions in which the inflaton fluctuates upwards expand much faster than regions in which the inflaton has a lower potential energy, and tend to dominate in terms of physical volume.", "It has been shown that any inflationary theory with an unbounded potential is eternal.", "There are well-known theorems that this steady state cannot continue forever into the past.", "Inflationary spacetime, which is similar to de Sitter space, is incomplete without a contracting region.", "However, unlike de Sitter space, fluctuations in a contracting inflationary space collapse to form a gravitational singularity, a point where densities become infinite.", "Therefore, it is necessary to have a theory for the Universe's initial conditions.In eternal inflation, regions with inflation have an exponentially growing volume, while regions that are not inflating don't.", "This suggests that the volume of the inflating part of the Universe in the global picture is always unimaginably larger than the part that has stopped inflating, even though inflation eventually ends as seen by any single pre-inflationary observer.", "Scientists disagree about how to assign a probability distribution to this hypothetical anthropic landscape.", "If the probability of different regions is counted by volume, one should expect that inflation will never end or applying boundary conditions that a local observer exists to observe it, that inflation will end as late as possible.Some physicists believe this paradox can be resolved by weighting observers by their pre-inflationary volume.", "Others believe that there is no resolution to the paradox and that the multiverse is a critical flaw in the inflationary paradigm.", "Paul Steinhardt, who first introduced the eternal inflationary model, later became one of its most vocal critics for this reason.===Initial conditions===Some physicists have tried to avoid the initial conditions problem by proposing models for an eternally inflating universe with no origin.", "These models propose that while the Universe, on the largest scales, expands exponentially it was, is and always will be, spatially infinite and has existed, and will exist, forever.Other proposals attempt to describe the ex nihilo creation of the Universe based on quantum cosmology and the following inflation.", "Vilenkin put forth one such scenario.", "Hartle and Hawking offered the no-boundary proposal for the initial creation of the Universe in which inflation comes about naturally.Guth described the inflationary universe as the \"ultimate free lunch\": new universes, similar to our own, are continually produced in a vast inflating background.", "Gravitational interactions, in this case, circumvent (but do not violate) the first law of thermodynamics (energy conservation) and the second law of thermodynamics (entropy and the arrow of time problem).", "However, while there is consensus that this solves the initial conditions problem, some have disputed this, as it is much more likely that the Universe came about by a quantum fluctuation.", "Don Page was an outspoken critic of inflation because of this anomaly.", "He stressed that the thermodynamic arrow of time necessitates low entropy initial conditions, which would be highly unlikely.", "According to them, rather than solving this problem, the inflation theory aggravates it – the reheating at the end of the inflation era increases entropy, making it necessary for the initial state of the Universe to be even more orderly than in other Big Bang theories with no inflation phase.Hawking and Page later found ambiguous results when they attempted to compute the probability of inflation in the Hartle–Hawking initial state.", "Other authors have argued that, since inflation is eternal, the probability doesn't matter as long as it is not precisely zero: once it starts, inflation perpetuates itself and quickly dominates the Universe.", "However, Albrecht and Lorenzo Sorbo argued that the probability of an inflationary cosmos, consistent with today's observations, emerging by a random fluctuation from some pre-existent state is much higher than that of a non-inflationary cosmos.", "This is because the \"seed\" amount of non-gravitational energy required for the inflationary cosmos is so much less than that for a non-inflationary alternative, which outweighs any entropic considerations.Another problem that has occasionally been mentioned is the trans-Planckian problem or trans-Planckian effects.", "Since the energy scale of inflation and the Planck scale are relatively close, some of the quantum fluctuations that have made up the structure in our universe were smaller than the Planck length before inflation.", "Therefore, there ought to be corrections from Planck-scale physics, in particular the unknown quantum theory of gravity.", "Some disagreement remains about the magnitude of this effect: about whether it is just on the threshold of detectability or completely undetectable.===Hybrid inflation===Another kind of inflation, called ''hybrid inflation'', is an extension of new inflation.", "It introduces additional scalar fields, so that while one of the scalar fields is responsible for normal slow roll inflation, another triggers the end of inflation: when inflation has continued for sufficiently long, it becomes favorable to the second field to decay into a much lower energy state.In hybrid inflation, one scalar field is responsible for most of the energy density (thus determining the rate of expansion), while another is responsible for the slow roll (thus determining the period of inflation and its termination).", "Thus fluctuations in the former inflaton would not affect inflation termination, while fluctuations in the latter would not affect the rate of expansion.", "Therefore, hybrid inflation is not eternal.", "When the second (slow-rolling) inflaton reaches the bottom of its potential, it changes the location of the minimum of the first inflaton's potential, which leads to a fast roll of the inflaton down its potential, leading to termination of inflation.===Relation to dark energy===Dark energy is broadly similar to inflation and is thought to be causing the expansion of the present-day universe to accelerate.", "However, the energy scale of dark energy is much lower,  GeV, roughly 27 orders of magnitude less than the scale of inflation.===Inflation and string cosmology===The discovery of flux compactifications opened the way for reconciling inflation and string theory.", "''Brane inflation'' suggests that inflation arises from the motion of D-branes in the compactified geometry, usually towards a stack of anti-D-branes.", "This theory, governed by the ''Dirac–Born–Infeld action'', is different from ordinary inflation.", "The dynamics are not completely understood.", "It appears that special conditions are necessary since inflation occurs in tunneling between two vacua in the string landscape.", "The process of tunneling between two vacua is a form of old inflation, but new inflation must then occur by some other mechanism.===Inflation and loop quantum gravity===When investigating the effects the theory of loop quantum gravity would have on cosmology, a loop quantum cosmology model has evolved that provides a possible mechanism for cosmological inflation.", "Loop quantum gravity assumes a quantized spacetime.", "If the energy density is larger than can be held by the quantized spacetime, it is thought to bounce back." ], [ "Alternatives and adjuncts", "Other models have been advanced that are claimed to explain some or all of the observations addressed by inflation.=== Big bounce ===The big bounce hypothesis attempts to replace the cosmic singularity with a cosmic contraction and bounce, thereby explaining the initial conditions that led to the big bang.The flatness and horizon problems are naturally solved in the Einstein–Cartan–Sciama–Kibble theory of gravity, without needing an exotic form of matter or free parameters.This theory extends general relativity by removing a constraint of the symmetry of the affine connection and regarding its antisymmetric part, the torsion tensor, as a dynamical variable.", "The minimal coupling between torsion and Dirac spinors generates a spin-spin interaction that is significant in fermionic matter at extremely high densities.", "Such an interaction averts the unphysical Big Bang singularity, replacing it with a cusp-like bounce at a finite minimum scale factor, before which the Universe was contracting.", "The rapid expansion immediately after the Big Bounce explains why the present Universe at largest scales appears spatially flat, homogeneous and isotropic.", "As the density of the Universe decreases, the effects of torsion weaken and the Universe smoothly enters the radiation-dominated era.=== Ekpyrotic and cyclic models ===The ekpyrotic and cyclic models are also considered adjuncts to inflation.", "These models solve the horizon problem through an expanding epoch well ''before'' the Big Bang, and then generate the required spectrum of primordial density perturbations during a contracting phase leading to a Big Crunch.", "The Universe passes through the Big Crunch and emerges in a hot Big Bang phase.", "In this sense they are reminiscent of Richard Chace Tolman's oscillatory universe; in Tolman's model, however, the total age of the Universe is necessarily finite, while in these models this is not necessarily so.", "Whether the correct spectrum of density fluctuations can be produced, and whether the Universe can successfully navigate the Big Bang/Big Crunch transition, remains a topic of controversy and current research.", "Ekpyrotic models avoid the magnetic monopole problem as long as the temperature at the Big Crunch/Big Bang transition remains below the Grand Unified Scale, as this is the temperature required to produce magnetic monopoles in the first place.", "As things stand, there is no evidence of any 'slowing down' of the expansion, but this is not surprising as each cycle is expected to last on the order of a trillion years.=== String gas cosmology ===String theory requires that, in addition to the three observable spatial dimensions, additional dimensions exist that are curled up or compactified (see also Kaluza–Klein theory).", "Extra dimensions appear as a frequent component of supergravity models and other approaches to quantum gravity.", "This raised the contingent question of why four space-time dimensions became large and the rest became unobservably small.", "An attempt to address this question, called ''string gas cosmology'', was proposed by Robert Brandenberger and Cumrun Vafa.", "This model focuses on the dynamics of the early universe considered as a hot gas of strings.", "Brandenberger and Vafa show that a dimension of spacetime can only expand if the strings that wind around it can efficiently annihilate each other.", "Each string is a one-dimensional object, and the largest number of dimensions in which two strings will generically intersect (and, presumably, annihilate) is three.", "Therefore, the most likely number of non-compact (large) spatial dimensions is three.", "Current work on this model centers on whether it can succeed in stabilizing the size of the compactified dimensions and produce the correct spectrum of primordial density perturbations.", "The original model did not \"solve the entropy and flatness problems of standard cosmology\", although Brandenburger and coauthors later argued that these problems can be eliminated by implementing string gas cosmology in the context of a bouncing-universe scenario.=== Varying ''c'' ===Cosmological models employing a variable speed of light have been proposed to resolve the horizon problem of and provide an alternative to cosmic inflation.", "In the VSL models, the fundamental constant ''c'', denoting the speed of light in vacuum, is greater in the early universe than its present value, effectively increasing the particle horizon at the time of decoupling sufficiently to account for the observed isotropy of the CMB." ], [ "Criticisms", "Since its introduction by Alan Guth in 1980, the inflationary paradigm has become widely accepted.", "Nevertheless, many physicists, mathematicians, and philosophers of science have voiced criticisms, claiming untestable predictions and a lack of serious empirical support.", "In 1999, John Earman and Jesús Mosterín published a thorough critical review of inflationary cosmology, concluding,: \"we do not think that there are, as yet, good grounds for admitting any of the models of inflation into the standard core of cosmology.", "\"As pointed out by Roger Penrose from 1986 on, in order to work, inflation requires extremely specific initial conditions of its own, so that the problem (or pseudo-problem) of initial conditions is not solved:: \"There is something fundamentally misconceived about trying to explain the uniformity of the early universe as resulting from a thermalization process.", "... For, if the thermalization is actually doing anything ... then it represents a definite increasing of the entropy.", "Thus, the universe would have been even more special before the thermalization than after.", "\"The problem of specific or \"fine-tuned\" initial conditions would not have been solved; it would have gotten worse.", "At a conference in 2015, Penrose said that: \"inflation isn't falsifiable, it's falsified.", "... BICEP did a wonderful service by bringing all the Inflation-ists out of their shell, and giving them a black eye.", "\"A recurrent criticism of inflation is that the invoked inflaton field does not correspond to any known physical field, and that its potential energy curve seems to be an ad hoc contrivance to accommodate almost any data obtainable.", "Paul Steinhardt, one of the founding fathers of inflationary cosmology, has recently become one of its sharpest critics.", "He calls 'bad inflation' a period of accelerated expansion whose outcome conflicts with observations, and 'good inflation' one compatible with them:: \"Not only is bad inflation more likely than good inflation, but no inflation is more likely than either ... Roger Penrose considered all the possible configurations of the inflaton and gravitational fields.", "Some of these configurations lead to inflation ... Other configurations lead to a uniform, flat universe directly – without inflation.", "Obtaining a flat universe is unlikely overall.", "Penrose's shocking conclusion, though, was that obtaining a flat universe without inflation is much more likely than with inflation – by a factor of 10 to the googol power!", "\"Together with Anna Ijjas and Abraham Loeb, he wrote articles claiming that the inflationary paradigm is in trouble in view of the data from the Planck satellite.Counter-arguments were presented by Alan Guth, David Kaiser, and Yasunori Nomuraand by Andrei Linde,saying that: \"cosmic inflation is on a stronger footing than ever before\"." ], [ "See also" ], [ "Notes" ], [ "References" ], [ "Sources" ], [ "External links", "* Was Cosmic Inflation The 'Bang' Of The Big Bang?, by Alan Guth, 1997* * update 2004 by Andrew Liddle* * * The Growth of Inflation ''Symmetry'', December 2004* Guth's logbook showing the original idea* WMAP Bolsters Case for Cosmic Inflation, March 2006* NASA March 2006 WMAP press release * Max Tegmark's ''Our Mathematical Universe'' (2014), \"Chapter 5: Inflation\"" ] ]

[ [ "Candela" ], [ "Introduction", "The '''candela''' ( or ; symbol: '''cd''') is the unit of luminous intensity in the International System of Units (SI).", "It measures luminous power per unit solid angle emitted by a light source in a particular direction.", "Luminous intensity is analogous to radiant intensity, but instead of simply adding up the contributions of every wavelength of light in the source's spectrum, the contribution of each wavelength is weighted by the luminous efficiency function, the model of the sensitivity of the human eye to different wavelengths, standardized by the CIE and ISO.", "A common wax candle emits light with a luminous intensity of roughly one candela.", "If emission in some directions is blocked by an opaque barrier, the emission would still be approximately one candela in the directions that are not obscured.The word ''candela'' is Latin for ''candle''.", "The old name \"candle\" is still sometimes used, as in ''foot-candle'' and the modern definition of ''candlepower''." ], [ "Definition", "The 26th General Conference on Weights and Measures (CGPM) redefined the candela in 2018.The new definition, which took effect on 20 May 2019, is:The candela ... is defined by taking the fixed numerical value of the luminous efficacy of monochromatic radiation of frequency , ''K''cd, to be 683 when expressed in the unit lm W−1, which is equal to , or , where the kilogram, metre and second are defined in terms of ''h'', ''c'' and Δ''ν''Cs.===Explanation===upright=1.5The frequency chosen is in the visible spectrum near green, corresponding to a wavelength of about 555 nanometres.", "The human eye, when adapted for bright conditions, is most sensitive near this frequency.", "Under these conditions, photopic vision dominates the visual perception of our eyes over the scotopic vision.", "At other frequencies, more radiant intensity is required to achieve the same luminous intensity, according to the frequency response of the human eye.", "The luminous intensity for light of a particular wavelength ''λ'' is given bywhere is the luminous intensity, is the radiant intensity and is the photopic luminous efficiency function.", "If more than one wavelength is present (as is usually the case), one must integrate over the spectrum of wavelengths to get the total luminous intensity.===Examples===*A common candle emits light with roughly 1 cd luminous intensity.", "*A 25 W compact fluorescent light bulb puts out around 1700 lumens; if that light is radiated equally in all directions (i.e.", "over 4 steradians), it will have an intensity of *Focused into a 20° beam (0.095 steradians), the same light bulb would have an intensity of around 18,000 cd within the beam." ], [ "History", "Prior to 1948, various standards for luminous intensity were in use in a number of countries.", "These were typically based on the brightness of the flame from a \"standard candle\" of defined composition, or the brightness of an incandescent filament of specific design.", "One of the best-known of these was the English standard of candlepower.", "One candlepower was the light produced by a pure spermaceti candle weighing one sixth of a pound and burning at a rate of 120 grains per hour.", "Germany, Austria and Scandinavia used the Hefnerkerze, a unit based on the output of a Hefner lamp.A better standard for luminous intensity was needed.", "In 1884, Jules Violle had proposed a standard based on the light emitted by 1 cm2 of platinum at its melting point (or freezing point).", "The resulting unit of intensity, called the \"violle\", was roughly equal to 60 English candlepower.", "Platinum was convenient for this purpose because it had a high enough melting point, was not prone to oxidation, and could be obtained in pure form.", "Violle showed that the intensity emitted by pure platinum was strictly dependent on its temperature, and so platinum at its melting point should have a consistent luminous intensity.", "In practice, realizing a standard based on Violle's proposal turned out to be more difficult than expected.", "Impurities on the surface of the platinum could directly affect its emissivity, and in addition impurities could affect the luminous intensity by altering the melting point.", "Over the following half century various scientists tried to make a practical intensity standard based on incandescent platinum.", "The successful approach was to suspend a hollow shell of thorium dioxide with a small hole in it in a bath of molten platinum.", "The shell (cavity) serves as a black body, producing black-body radiation that depends on the temperature and is not sensitive to details of how the device is constructed.In 1937, the ''Commission Internationale de l'Éclairage'' (International Commission on Illumination) and the CIPM proposed a \"new candle\" based on this concept, with value chosen to make it similar to the earlier unit candlepower.", "The decision was promulgated by the CIPM in 1946:The value of the '''new candle''' is such that the brightness of the full radiator at the temperature of solidification of platinum is 60 new candles per square centimetre.It was then ratified in 1948 by the 9th CGPM which adopted a new name for this unit, the ''candela''.", "In 1967 the 13th CGPM removed the term \"new candle\" and gave an amended version of the candela definition, specifying the atmospheric pressure applied to the freezing platinum:The candela is the luminous intensity, in the perpendicular direction, of a surface of square metre of a black body at the temperature of freezing platinum under a pressure of  newtons per square metre.In 1979, because of the difficulties in realizing a Planck radiator at high temperatures and the new possibilities offered by radiometry, the 16th CGPM adopted a new definition of the candela:The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency and that has a radiant intensity in that direction of  watt per steradian.The definition describes how to produce a light source that (by definition) emits one candela, but does not specify the luminous efficiency function for weighting radiation at other frequencies.", "Such a source could then be used to calibrate instruments designed to measure luminous intensity with reference to a specified luminous efficiency function.", "An appendix to the SI Brochure makes it clear that the luminous efficiency function is not uniquely specified, but must be selected to fully define the candela.The arbitrary (1/683) term was chosen so that the new definition would precisely match the old definition.", "Although the candela is now defined in terms of the second (an SI base unit) and the watt (a derived SI unit), the candela remains a base unit of the SI system, by definition.The 26th CGPM approved the modern definition of the candela in 2018 as part of the 2019 redefinition of SI base units, which redefined the SI base units in terms of fundamental physical constants." ], [ "SI photometric light units", "===Relationships between luminous intensity, luminous flux, and illuminance===If a source emits a known luminous intensity (in candelas) in a well-defined cone, the total luminous flux in lumens is given bywhere is the ''radiation angle'' of the lamp—the full vertex angle of the emission cone.", "For example, a lamp that emits 590 cd with a radiation angle of 40° emits about 224 lumens.", "See MR16 for emission angles of some common lamps.If the source emits light uniformly in all directions, the flux can be found by multiplying the intensity by 4: a uniform 1 candela source emits 12.6 lumens.For the purpose of measuring illumination, the candela is not a practical unit, as it only applies to idealized point light sources, each approximated by a source small compared to the distance from which its luminous radiation is measured, also assuming that it is done so in the absence of other light sources.", "What gets directly measured by a light meter is incident light on a sensor of finite area, i.e.", "illuminance in lm/m2 (lux).", "However, if designing illumination from many point light sources, like light bulbs, of known approximate omnidirectionally uniform intensities, the contributions to illuminance from incoherent light being additive, it is mathematically estimated as follows.", "If is the position of the ''i''th source of uniform intensity , and is the unit vector normal to the illuminated elemental opaque area being measured, and provided that all light sources lie in the same half-space divided by the plane of this area,In the case of a single point light source of intensity ''Iv'', at a distance ''r'' and normally incident, this reduces to" ], [ "SI multiples", "Like other SI units, the candela can also be modified by adding a metric prefix that multiplies it by a power of 10, for example millicandela (mcd) for 10−3 candela." ], [ "References" ] ]

[ [ "Condensed matter physics" ], [ "Introduction", "'''Condensed matter physics''' is the field of physics that deals with the macroscopic and microscopic physical properties of matter, especially the solid and liquid phases that arise from electromagnetic forces between atoms and electrons.", "More generally, the subject deals with condensed phases of matter: systems of many constituents with strong interactions among them.", "More exotic condensed phases include the superconducting phase exhibited by certain materials at extremely low cryogenic temperatures, the ferromagnetic and antiferromagnetic phases of spins on crystal lattices of atoms, the Bose–Einstein condensates found in ultracold atomic systems, and liquid crystals.", "Condensed matter physicists seek to understand the behavior of these phases by experiments to measure various material properties, and by applying the physical laws of quantum mechanics, electromagnetism, statistical mechanics, and other physics theories to develop mathematical models and predict the properties of extremely large groups of atoms.The diversity of systems and phenomena available for study makes condensed matter physics the most active field of contemporary physics: one third of all American physicists self-identify as condensed matter physicists, and the Division of Condensed Matter Physics is the largest division of the American Physical Society.", "These include solid state and soft matter physicists, who study quantum and non-quantum physical properties of matter respectively.", "Both types study a great range of materials, providing many research, funding and employment opportunities.", "The field overlaps with chemistry, materials science, engineering and nanotechnology, and relates closely to atomic physics and biophysics.", "The theoretical physics of condensed matter shares important concepts and methods with that of particle physics and nuclear physics.A variety of topics in physics such as crystallography, metallurgy, elasticity, magnetism, etc., were treated as distinct areas until the 1940s, when they were grouped together as ''solid-state physics''.", "Around the 1960s, the study of physical properties of liquids was added to this list, forming the basis for the more comprehensive specialty of condensed matter physics.", "The Bell Telephone Laboratories was one of the first institutes to conduct a research program in condensed matter physics.", "According to the founding director of the Max Planck Institute for Solid State Research, physics professor Manuel Cardona, it was Albert Einstein who created the modern field of condensed matter physics starting with his seminal 1905 article on the photoelectric effect and photoluminescence which opened the fields of photoelectron spectroscopy and photoluminescence spectroscopy, and later his 1907 article on the specific heat of solids which introduced, for the first time, the effect of lattice vibrations on the thermodynamic properties of crystals, in particular the specific heat.", "Deputy Director of the Yale Quantum Institute A. Douglas Stone makes a similar priority case for Einstein in his work on the synthetic history of quantum mechanics." ], [ "Etymology", "According to physicist Philip Warren Anderson, the use of the term \"condensed matter\" to designate a field of study was coined by him and Volker Heine, when they changed the name of their group at the Cavendish Laboratories, Cambridge from ''Solid state theory'' to ''Theory of Condensed Matter'' in 1967, as they felt it better included their interest in liquids, nuclear matter, and so on.", "Although Anderson and Heine helped popularize the name \"condensed matter\", it had been used in Europe for some years, most prominently in the Springer-Verlag journal ''Physics of Condensed Matter'', launched in 1963.The name \"condensed matter physics\" emphasized the commonality of scientific problems encountered by physicists working on solids, liquids, plasmas, and other complex matter, whereas \"solid state physics\" was often associated with restricted industrial applications of metals and semiconductors.", "In the 1960s and 70s, some physicists felt the more comprehensive name better fit the funding environment and Cold War politics of the time.References to \"condensed\" states can be traced to earlier sources.", "For example, in the introduction to his 1947 book ''Kinetic Theory of Liquids'', Yakov Frenkel proposed that \"The kinetic theory of liquids must accordingly be developed as a generalization and extension of the kinetic theory of solid bodies.", "As a matter of fact, it would be more correct to unify them under the title of 'condensed bodies'\"." ], [ "History", "===Classical physics===Heike Kamerlingh Onnes and Johannes van der Waals with the helium ''liquefactor'' at Leiden in 1908One of the first studies of condensed states of matter was by English chemist Humphry Davy, in the first decades of the nineteenth century.", "Davy observed that of the forty chemical elements known at the time, twenty-six had metallic properties such as lustre, ductility and high electrical and thermal conductivity.", "This indicated that the atoms in John Dalton's atomic theory were not indivisible as Dalton claimed, but had inner structure.", "Davy further claimed that elements that were then believed to be gases, such as nitrogen and hydrogen could be liquefied under the right conditions and would then behave as metals.In 1823, Michael Faraday, then an assistant in Davy's lab, successfully liquefied chlorine and went on to liquefy all known gaseous elements, except for nitrogen, hydrogen, and oxygen.", "Shortly after, in 1869, Irish chemist Thomas Andrews studied the phase transition from a liquid to a gas and coined the term critical point to describe the condition where a gas and a liquid were indistinguishable as phases, and Dutch physicist Johannes van der Waals supplied the theoretical framework which allowed the prediction of critical behavior based on measurements at much higher temperatures.", "By 1908, James Dewar and Heike Kamerlingh Onnes were successfully able to liquefy hydrogen and then newly discovered helium, respectively.Paul Drude in 1900 proposed the first theoretical model for a classical electron moving through a metallic solid.", "Drude's model described properties of metals in terms of a gas of free electrons, and was the first microscopic model to explain empirical observations such as the Wiedemann–Franz law.", "However, despite the success of Drude's model, it had one notable problem: it was unable to correctly explain the electronic contribution to the specific heat and magnetic properties of metals, and the temperature dependence of resistivity at low temperatures.In 1911, three years after helium was first liquefied, Onnes working at University of Leiden discovered superconductivity in mercury, when he observed the electrical resistivity of mercury to vanish at temperatures below a certain value.", "The phenomenon completely surprised the best theoretical physicists of the time, and it remained unexplained for several decades.", "Albert Einstein, in 1922, said regarding contemporary theories of superconductivity that \"with our far-reaching ignorance of the quantum mechanics of composite systems we are very far from being able to compose a theory out of these vague ideas.", "\"===Advent of quantum mechanics===Drude's classical model was augmented by Wolfgang Pauli, Arnold Sommerfeld, Felix Bloch and other physicists.", "Pauli realized that the free electrons in metal must obey the Fermi–Dirac statistics.", "Using this idea, he developed the theory of paramagnetism in 1926.Shortly after, Sommerfeld incorporated the Fermi–Dirac statistics into the free electron model and made it better to explain the heat capacity.", "Two years later, Bloch used quantum mechanics to describe the motion of an electron in a periodic lattice.", "The mathematics of crystal structures developed by Auguste Bravais, Yevgraf Fyodorov and others was used to classify crystals by their symmetry group, and tables of crystal structures were the basis for the series ''International Tables of Crystallography'', first published in 1935.Band structure calculations was first used in 1930 to predict the properties of new materials, and in 1947 John Bardeen, Walter Brattain and William Shockley developed the first semiconductor-based transistor, heralding a revolution in electronics.A replica of the first point-contact transistor in Bell labsIn 1879, Edwin Herbert Hall working at the Johns Hopkins University discovered a voltage developed across conductors transverse to an electric current in the conductor and magnetic field perpendicular to the current.", "This phenomenon arising due to the nature of charge carriers in the conductor came to be termed the Hall effect, but it was not properly explained at the time, since the electron was not experimentally discovered until 18 years later.", "After the advent of quantum mechanics, Lev Landau in 1930 developed the theory of Landau quantization and laid the foundation for the theoretical explanation for the quantum Hall effect discovered half a century later.Magnetism as a property of matter has been known in China since 4000 BC.", "However, the first modern studies of magnetism only started with the development of electrodynamics by Faraday, Maxwell and others in the nineteenth century, which included classifying materials as ferromagnetic, paramagnetic and diamagnetic based on their response to magnetization.", "Pierre Curie studied the dependence of magnetization on temperature and discovered the Curie point phase transition in ferromagnetic materials.", "In 1906, Pierre Weiss introduced the concept of magnetic domains to explain the main properties of ferromagnets.", "The first attempt at a microscopic description of magnetism was by Wilhelm Lenz and Ernst Ising through the Ising model that described magnetic materials as consisting of a periodic lattice of spins that collectively acquired magnetization.", "The Ising model was solved exactly to show that spontaneous magnetization can occur in one dimension and it is possible in higher-dimensional lattices.", "Further research such as by Bloch on spin waves and Néel on antiferromagnetism led to developing new magnetic materials with applications to magnetic storage devices.===Modern many-body physics===A magnet levitating above a high-temperature superconductor.", "Today some physicists are working to understand high-temperature superconductivity using the AdS/CFT correspondence.The Sommerfeld model and spin models for ferromagnetism illustrated the successful application of quantum mechanics to condensed matter problems in the 1930s.", "However, there still were several unsolved problems, most notably the description of superconductivity and the Kondo effect.", "After World War II, several ideas from quantum field theory were applied to condensed matter problems.", "These included recognition of collective excitation modes of solids and the important notion of a quasiparticle.", "Russian physicist Lev Landau used the idea for the Fermi liquid theory wherein low energy properties of interacting fermion systems were given in terms of what are now termed Landau-quasiparticles.", "Landau also developed a mean-field theory for continuous phase transitions, which described ordered phases as spontaneous breakdown of symmetry.", "The theory also introduced the notion of an order parameter to distinguish between ordered phases.", "Eventually in 1956, John Bardeen, Leon Cooper and Robert Schrieffer developed the so-called BCS theory of superconductivity, based on the discovery that arbitrarily small attraction between two electrons of opposite spin mediated by phonons in the lattice can give rise to a bound state called a Cooper pair.The quantum Hall effect: Components of the Hall resistivity as a function of the external magnetic fieldThe study of phase transitions and the critical behavior of observables, termed critical phenomena, was a major field of interest in the 1960s.", "Leo Kadanoff, Benjamin Widom and Michael Fisher developed the ideas of critical exponents and widom scaling.", "These ideas were unified by Kenneth G. Wilson in 1972, under the formalism of the renormalization group in the context of quantum field theory.The quantum Hall effect was discovered by Klaus von Klitzing, Dorda and Pepper in 1980 when they observed the Hall conductance to be integer multiples of a fundamental constant .", "(see figure) The effect was observed to be independent of parameters such as system size and impurities.", "In 1981, theorist Robert Laughlin proposed a theory explaining the unanticipated precision of the integral plateau.", "It also implied that the Hall conductance is proportional to a topological invariant, called Chern number, whose relevance for the band structure of solids was formulated by David J. Thouless and collaborators.", "Shortly after, in 1982, Horst Störmer and Daniel Tsui observed the fractional quantum Hall effect where the conductance was now a rational multiple of the constant .", "Laughlin, in 1983, realized that this was a consequence of quasiparticle interaction in the Hall states and formulated a variational method solution, named the Laughlin wavefunction.", "The study of topological properties of the fractional Hall effect remains an active field of research.", "Decades later, the aforementioned topological band theory advanced by David J. Thouless and collaborators was further expanded leading to the discovery of topological insulators.", "In 1986, Karl Müller and Johannes Bednorz discovered the first high temperature superconductor, La2-xBaxCuO4, which is superconducting at temperatures as high as 39 kelvin.", "It was realized that the high temperature superconductors are examples of strongly correlated materials where the electron–electron interactions play an important role.", "A satisfactory theoretical description of high-temperature superconductors is still not known and the field of strongly correlated materials continues to be an active research topic.In 2012, several groups released preprints which suggest that samarium hexaboride has the properties of a topological insulator in accord with the earlier theoretical predictions.", "Since samarium hexaboride is an established Kondo insulator, i.e.", "a strongly correlated electron material, it is expected that the existence of a topological Dirac surface state in this material would lead to a topological insulator with strong electronic correlations." ], [ "Theoretical", "Theoretical condensed matter physics involves the use of theoretical models to understand properties of states of matter.", "These include models to study the electronic properties of solids, such as the Drude model, the band structure and the density functional theory.", "Theoretical models have also been developed to study the physics of phase transitions, such as the Ginzburg–Landau theory, critical exponents and the use of mathematical methods of quantum field theory and the renormalization group.", "Modern theoretical studies involve the use of numerical computation of electronic structure and mathematical tools to understand phenomena such as high-temperature superconductivity, topological phases, and gauge symmetries.===Emergence===Theoretical understanding of condensed matter physics is closely related to the notion of emergence, wherein complex assemblies of particles behave in ways dramatically different from their individual constituents.", "For example, a range of phenomena related to high temperature superconductivity are understood poorly, although the microscopic physics of individual electrons and lattices is well known.", "Similarly, models of condensed matter systems have been studied where collective excitations behave like photons and electrons, thereby describing electromagnetism as an emergent phenomenon.", "Emergent properties can also occur at the interface between materials: one example is the lanthanum aluminate-strontium titanate interface, where two band-insulators are joined to create conductivity and superconductivity.===Electronic theory of solids===The metallic state has historically been an important building block for studying properties of solids.", "The first theoretical description of metals was given by Paul Drude in 1900 with the Drude model, which explained electrical and thermal properties by describing a metal as an ideal gas of then-newly discovered electrons.", "He was able to derive the empirical Wiedemann-Franz law and get results in close agreement with the experiments.", "This classical model was then improved by Arnold Sommerfeld who incorporated the Fermi–Dirac statistics of electrons and was able to explain the anomalous behavior of the specific heat of metals in the Wiedemann–Franz law.", "In 1912, The structure of crystalline solids was studied by Max von Laue and Paul Knipping, when they observed the X-ray diffraction pattern of crystals, and concluded that crystals get their structure from periodic lattices of atoms.", "In 1928, Swiss physicist Felix Bloch provided a wave function solution to the Schrödinger equation with a periodic potential, known as Bloch's theorem.Calculating electronic properties of metals by solving the many-body wavefunction is often computationally hard, and hence, approximation methods are needed to obtain meaningful predictions.", "The Thomas–Fermi theory, developed in the 1920s, was used to estimate system energy and electronic density by treating the local electron density as a variational parameter.", "Later in the 1930s, Douglas Hartree, Vladimir Fock and John Slater developed the so-called Hartree–Fock wavefunction as an improvement over the Thomas–Fermi model.", "The Hartree–Fock method accounted for exchange statistics of single particle electron wavefunctions.", "In general, it is very difficult to solve the Hartree–Fock equation.", "Only the free electron gas case can be solved exactly.", "Finally in 1964–65, Walter Kohn, Pierre Hohenberg and Lu Jeu Sham proposed the density functional theory (DFT) which gave realistic descriptions for bulk and surface properties of metals.", "The density functional theory has been widely used since the 1970s for band structure calculations of variety of solids.===Symmetry breaking===Some states of matter exhibit ''symmetry breaking'', where the relevant laws of physics possess some form of symmetry that is broken.", "A common example is crystalline solids, which break continuous translational symmetry.", "Other examples include magnetized ferromagnets, which break rotational symmetry, and more exotic states such as the ground state of a BCS superconductor, that breaks U(1) phase rotational symmetry.Goldstone's theorem in quantum field theory states that in a system with broken continuous symmetry, there may exist excitations with arbitrarily low energy, called the Goldstone bosons.", "For example, in crystalline solids, these correspond to phonons, which are quantized versions of lattice vibrations.===Phase transition===Phase transition refers to the change of phase of a system, which is brought about by change in an external parameter such as temperature, pressure, or molar composition.", "In a single-component system, a classical phase transition occurs at a temperature (at a specific pressure) where there is an abrupt change in the order of the system For example, when ice melts and becomes water, the ordered hexagonal crystal structure of ice is modified to a hydrogen bonded, mobile arrangement of water molecules.In quantum phase transitions, the temperature is set to absolute zero, and the non-thermal control parameter, such as pressure or magnetic field, causes the phase transitions when order is destroyed by quantum fluctuations originating from the Heisenberg uncertainty principle.", "Here, the different quantum phases of the system refer to distinct ground states of the Hamiltonian matrix.", "Understanding the behavior of quantum phase transition is important in the difficult tasks of explaining the properties of rare-earth magnetic insulators, high-temperature superconductors, and other substances.Two classes of phase transitions occur: ''first-order transitions'' and ''second-order'' or ''continuous transitions''.", "For the latter, the two phases involved do not co-exist at the transition temperature, also called the critical point.", "Near the critical point, systems undergo critical behavior, wherein several of their properties such as correlation length, specific heat, and magnetic susceptibility diverge exponentially.", "These critical phenomena present serious challenges to physicists because normal macroscopic laws are no longer valid in the region, and novel ideas and methods must be invented to find the new laws that can describe the system.The simplest theory that can describe continuous phase transitions is the Ginzburg–Landau theory, which works in the so-called mean-field approximation.", "However, it can only roughly explain continuous phase transition for ferroelectrics and type I superconductors which involves long range microscopic interactions.", "For other types of systems that involves short range interactions near the critical point, a better theory is needed.Near the critical point, the fluctuations happen over broad range of size scales while the feature of the whole system is scale invariant.", "Renormalization group methods successively average out the shortest wavelength fluctuations in stages while retaining their effects into the next stage.", "Thus, the changes of a physical system as viewed at different size scales can be investigated systematically.", "The methods, together with powerful computer simulation, contribute greatly to the explanation of the critical phenomena associated with continuous phase transition." ], [ "Experimental", "Experimental condensed matter physics involves the use of experimental probes to try to discover new properties of materials.", "Such probes include effects of electric and magnetic fields, measuring response functions, transport properties and thermometry.", "Commonly used experimental methods include spectroscopy, with probes such as X-rays, infrared light and inelastic neutron scattering; study of thermal response, such as specific heat and measuring transport via thermal and heat conduction.Image of X-ray diffraction pattern from a protein crystal.===Scattering===Several condensed matter experiments involve scattering of an experimental probe, such as X-ray, optical photons, neutrons, etc., on constituents of a material.", "The choice of scattering probe depends on the observation energy scale of interest.", "Visible light has energy on the scale of 1 electron volt (eV) and is used as a scattering probe to measure variations in material properties such as the dielectric constant and refractive index.", "X-rays have energies of the order of 10 keV and hence are able to probe atomic length scales, and are used to measure variations in electron charge density and crystal structure.Neutrons can also probe atomic length scales and are used to study the scattering off nuclei and electron spins and magnetization (as neutrons have spin but no charge).", "Coulomb and Mott scattering measurements can be made by using electron beams as scattering probes.", "Similarly, positron annihilation can be used as an indirect measurement of local electron density.", "Laser spectroscopy is an excellent tool for studying the microscopic properties of a medium, for example, to study forbidden transitions in media with nonlinear optical spectroscopy.", "===External magnetic fields===In experimental condensed matter physics, external magnetic fields act as thermodynamic variables that control the state, phase transitions and properties of material systems.", "Nuclear magnetic resonance (NMR) is a method by which external magnetic fields are used to find resonance modes of individual nuclei, thus giving information about the atomic, molecular, and bond structure of their environment.", "NMR experiments can be made in magnetic fields with strengths up to 60 tesla.", "Higher magnetic fields can improve the quality of NMR measurement data.", "Quantum oscillations is another experimental method where high magnetic fields are used to study material properties such as the geometry of the Fermi surface.", "High magnetic fields will be useful in experimental testing of the various theoretical predictions such as the quantized magnetoelectric effect, image magnetic monopole, and the half-integer quantum Hall effect.===Magnetic resonance spectroscopy===The local structure, as well as the structure of the nearest neighbour atoms, can be investigated in condensed matter with magnetic resonance methods, such as electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR), which are very sensitive to the details of the surrounding of nuclei and electrons by means of the hyperfine coupling.", "Both localized electrons and specific stable or unstable isotopes of the nuclei become the probe of these hyperfine interactions), which couple the electron or nuclear spin to the local electric and magnetic fields.", "These methods are suitable to study defects, diffusion, phase transitions and magnetic order.", "Common experimental methods include NMR, nuclear quadrupole resonance (NQR), implanted radioactive probes as in the case of muon spin spectroscopy (SR), Mössbauer spectroscopy, NMR and perturbed angular correlation (PAC).", "PAC is especially ideal for the study of phase changes at extreme temperatures above 2000 °C due to the temperature independence of the method.===Cold atomic gases===The first Bose–Einstein condensate observed in a gas of ultracold rubidium atoms.", "The blue and white areas represent higher density.Ultracold atom trapping in optical lattices is an experimental tool commonly used in condensed matter physics, and in atomic, molecular, and optical physics.", "The method involves using optical lasers to form an interference pattern, which acts as a ''lattice'', in which ions or atoms can be placed at very low temperatures.", "Cold atoms in optical lattices are used as ''quantum simulators'', that is, they act as controllable systems that can model behavior of more complicated systems, such as frustrated magnets.", "In particular, they are used to engineer one-, two- and three-dimensional lattices for a Hubbard model with pre-specified parameters, and to study phase transitions for antiferromagnetic and spin liquid ordering.In 1995, a gas of rubidium atoms cooled down to a temperature of 170 nK was used to experimentally realize the Bose–Einstein condensate, a novel state of matter originally predicted by S. N. Bose and Albert Einstein, wherein a large number of atoms occupy one quantum state." ], [ "Applications", "Computer simulation of ''nanogears'' made of fullerene molecules.", "It is hoped that advances in nanoscience will lead to machines working on the molecular scale.Research in condensed matter physics has given rise to several device applications, such as the development of the semiconductor transistor, laser technology, magnetic storage, liquid crystals, optical fibres and several phenomena studied in the context of nanotechnology.", "Methods such as scanning-tunneling microscopy can be used to control processes at the nanometer scale, and have given rise to the study of nanofabrication.", "Such molecular machines were developed for example by Nobel laurates in chemistry Ben Feringa, Jean-Pierre Sauvage and Fraser Stoddart.", "Feringa and his team developed multiple molecular machines such as the molecular car, molecular windmill and many more.In quantum computation, information is represented by quantum bits, or qubits.", "The qubits may decohere quickly before useful computation is completed.", "This serious problem must be solved before quantum computing may be realized.", "To solve this problem, several promising approaches are proposed in condensed matter physics, including Josephson junction qubits, spintronic qubits using the spin orientation of magnetic materials, or the topological non-Abelian anyons from fractional quantum Hall effect states.Condensed matter physics also has important uses for biomedicine, for example, the experimental method of magnetic resonance imaging, which is widely used in medical diagnosis." ], [ "See also", "* * * * * * * * * *" ], [ "Notes" ], [ "References" ], [ "Further reading", "* Anderson, Philip W. (2018-03-09).", "''Basic Notions Of Condensed Matter Physics''.", "CRC Press.", ".", "*Girvin, Steven M.; Yang, Kun (2019-02-28).", "''Modern Condensed Matter Physics''.", "Cambridge University Press.", ".", "*Coleman, Piers (2015). ''", "Introduction to Many-Body Physics'', Cambridge University Press, .", "*P.", "M. Chaikin and T. C. Lubensky (2000).", "''Principles of Condensed Matter Physics'', Cambridge University Press; 1st edition, * Alexander Altland and Ben Simons (2006).", "''Condensed Matter Field Theory'', Cambridge University Press, .", "* Michael P. Marder (2010).", "''Condensed Matter Physics, second edition'', John Wiley and Sons, .", "*Lillian Hoddeson, Ernest Braun, Jürgen Teichmann and Spencer Weart, eds.", "(1992).", "''Out of the Crystal Maze: Chapters from the History of Solid State Physics'', Oxford University Press, ." ], [ "External links", "*" ] ]

[ [ "Cultural anthropology" ], [ "Introduction", "'''Cultural anthropology''' is a branch of anthropology focused on the study of cultural variation among humans.", "It is in contrast to social anthropology, which perceives cultural variation as a subset of a posited anthropological constant.", "The term sociocultural anthropology includes both cultural and social anthropology traditions.Edward Burnett Tylor, founder of cultural anthropologyAnthropologists have pointed out that through culture, people can adapt to their environment in non-genetic ways, so people living in different environments will often have different cultures.", "Much of anthropological theory has originated in an appreciation of and interest in the tension between the local (particular cultures) and the global (a universal human nature, or the web of connections between people in distinct places/circumstances).Cultural anthropology has a rich methodology, including participant observation (often called fieldwork because it requires the anthropologist spending an extended period of time at the research location), interviews, and surveys." ], [ "History", "The rise of cultural anthropology took place within the context of the late 19th century, when questions regarding which cultures were \"primitive\" and which were \"civilized\" occupied the mind of not only Freud, but many others.", "Colonialism and its processes increasingly brought European thinkers into direct or indirect contact with \"primitive others\".", "The first generation of cultural anthropologists were interested in the relative status of various humans, some of whom had modern advanced technologies, while others lacked anything but face-to-face communication techniques and still lived a Paleolithic lifestyle." ], [ "Theoretical foundations", "===The concept of culture===One of the earliest articulations of the anthropological meaning of the term \"culture\" came from Sir Edward Tylor: \"Culture, or civilization, taken in its broad, ethnographic sense, is that complex whole which includes knowledge, belief, art, morals, law, custom, and any other capabilities and habits acquired by man as a member of society.\"", "The term \"civilization\" later gave way to definitions given by V. Gordon Childe, with culture forming an umbrella term and civilization becoming a particular kind of culture.According to Kay Milton, former director of anthropology research at Queens University Belfast, culture can be general or specific.", "This means culture can be something applied to all human beings or it can be specific to a certain group of people such as African American culture or Irish American culture.", "Specific cultures are structured systems which means they are organized very specifically and adding or taking away any element from that system may disrupt it.===The critique of evolutionism===Anthropology is concerned with the lives of people in different parts of the world, particularly in relation to the discourse of beliefs and practices.", "In addressing this question, ethnologists in the 19th century divided into two schools of thought.", "Some, like Grafton Elliot Smith, argued that different groups must have learned from one another somehow, however indirectly; in other words, they argued that cultural traits spread from one place to another, or \"diffused\".In the unilineal evolution model at left, all cultures progress through set stages, while in the multilineal evolution model at right, distinctive culture histories are emphasized.Other ethnologists argued that different groups had the capability of creating similar beliefs and practices independently.", "Some of those who advocated \"independent invention\", like Lewis Henry Morgan, additionally supposed that similarities meant that different groups had passed through the same stages of cultural evolution (See also classical social evolutionism).", "Morgan, in particular, acknowledged that certain forms of society and culture could not possibly have arisen before others.", "For example, industrial farming could not have been invented before simple farming, and metallurgy could not have developed without previous non-smelting processes involving metals (such as simple ground collection or mining).", "Morgan, like other 19th century social evolutionists, believed there was a more or less orderly progression from the primitive to the civilized.20th-century anthropologists largely reject the notion that all human societies must pass through the same stages in the same order, on the grounds that such a notion does not fit the empirical facts.", "Some 20th-century ethnologists, like Julian Steward, have instead argued that such similarities reflected similar adaptations to similar environments.", "Although 19th-century ethnologists saw \"diffusion\" and \"independent invention\" as mutually exclusive and competing theories, most ethnographers quickly reached a consensus that both processes occur, and that both can plausibly account for cross-cultural similarities.", "But these ethnographers also pointed out the superficiality of many such similarities.", "They noted that even traits that spread through diffusion often were given different meanings and function from one society to another.", "Analyses of large human concentrations in big cities, in multidisciplinary studies by Ronald Daus, show how new methods may be applied to the understanding of man living in a global world and how it was caused by the action of extra-European nations, so highlighting the role of Ethics in modern anthropology.Accordingly, most of these anthropologists showed less interest in comparing cultures, generalizing about human nature, or discovering universal laws of cultural development, than in understanding particular cultures in those cultures' own terms.", "Such ethnographers and their students promoted the idea of \"cultural relativism\", the view that one can only understand another person's beliefs and behaviors in the context of the culture in which they live or lived.Others, such as Claude Lévi-Strauss (who was influenced both by American cultural anthropology and by French Durkheimian sociology), have argued that apparently similar patterns of development reflect fundamental similarities in the structure of human thought (see structuralism).", "By the mid-20th century, the number of examples of people skipping stages, such as going from hunter-gatherers to post-industrial service occupations in one generation, were so numerous that 19th-century evolutionism was effectively disproved.===Cultural relativism===Cultural relativism is a principle that was established as axiomatic in anthropological research by Franz Boas and later popularized by his students.", "Boas first articulated the idea in 1887: \"...civilization is not something absolute, but ... is relative, and ... our ideas and conceptions are true only so far as our civilization goes.\"", "Although Boas did not coin the term, it became common among anthropologists after Boas' death in 1942, to express their synthesis of a number of ideas Boas had developed.", "Boas believed that the sweep of cultures, to be found in connection with any sub-species, is so vast and pervasive that there cannot be a relationship between culture and race.", "Cultural relativism involves specific epistemological and methodological claims.", "Whether or not these claims require a specific ethical stance is a matter of debate.", "This principle should not be confused with moral relativism.Cultural relativism was in part a response to Western ethnocentrism.", "Ethnocentrism may take obvious forms, in which one consciously believes that one's people's arts are the most beautiful, values the most virtuous, and beliefs the most truthful.", "Boas, originally trained in physics and geography, and heavily influenced by the thought of Kant, Herder, and von Humboldt, argued that one's culture may mediate and thus limit one's perceptions in less obvious ways.", "This understanding of culture confronts anthropologists with two problems: first, how to escape the unconscious bonds of one's own culture, which inevitably bias our perceptions of and reactions to the world, and second, how to make sense of an unfamiliar culture.", "The principle of cultural relativism thus forced anthropologists to develop innovative methods and heuristic strategies.Boas and his students realized that if they were to conduct scientific research in other cultures, they would need to employ methods that would help them escape the limits of their own ethnocentrism.", "One such method is that of ethnography.", "This method advocates living with people of another culture for an extended period of time to learn the local language and be enculturated, at least partially, into that culture.", "In this context, cultural relativism is of fundamental methodological importance, because it calls attention to the importance of the local context in understanding the meaning of particular human beliefs and activities.", "Thus, in 1948 Virginia Heyer wrote, \"Cultural relativity, to phrase it in starkest abstraction, states the relativity of the part to the whole.", "The part gains its cultural significance by its place in the whole, and cannot retain its integrity in a different situation.", "\"===Theoretical approaches===* Actor–network theory* Cultural materialism* Culture theory* Feminist anthropology* Functionalism* Symbolic and interpretive anthropology* Political economy in anthropology* Practice theory* Structuralism* Post-structuralism* Systems theory in anthropology===Comparison with social anthropology===The rubric ''cultural'' anthropology is generally applied to ethnographic works that are holistic in approach, are oriented to the ways in which culture affects individual experience or aim to provide a rounded view of the knowledge, customs, and institutions of a people.", "''Social'' anthropology is a term applied to ethnographic works that attempt to isolate a particular system of social relations such as those that comprise domestic life, economy, law, politics, or religion, give analytical priority to the organizational bases of social life, and attend to cultural phenomena as somewhat secondary to the main issues of social scientific inquiry.Parallel with the rise of cultural anthropology in the United States, social anthropology developed as an academic discipline in Britain and in France." ], [ "Foundational thinkers", "===Lewis Henry Morgan===Lewis Henry Morgan (1818–1881), a lawyer from Rochester, New York, became an advocate for and ethnological scholar of the Iroquois.", "His comparative analyses of religion, government, material culture, and especially kinship patterns proved to be influential contributions to the field of anthropology.", "Like other scholars of his day (such as Edward Tylor), Morgan argued that human societies could be classified into categories of cultural evolution on a scale of progression that ranged from ''savagery'', to ''barbarism'', to ''civilization''.", "Generally, Morgan used technology (such as bowmaking or pottery) as an indicator of position on this scale.=== Franz Boas, founder of the modern discipline === Franz Boas (1858–1942), one of the pioneers of modern anthropology, often called the \"Father of American Anthropology\"Franz Boas (1858–1942) established academic anthropology in the United States in opposition to Morgan's evolutionary perspective.", "His approach was empirical, skeptical of overgeneralizations, and eschewed attempts to establish universal laws.", "For example, Boas studied immigrant children to demonstrate that biological race was not immutable, and that human conduct and behavior resulted from nurture, rather than nature.Influenced by the German tradition, Boas argued that the world was full of distinct ''cultures,'' rather than societies whose evolution could be measured by the extent of \"civilization\" they had.", "He believed that each culture has to be studied in its particularity, and argued that cross-cultural generalizations, like those made in the natural sciences, were not possible.In doing so, he fought discrimination against immigrants, blacks, and indigenous peoples of the Americas.", "Many American anthropologists adopted his agenda for social reform, and theories of race continue to be popular subjects for anthropologists today.", "The so-called \"Four Field Approach\" has its origins in Boasian Anthropology, dividing the discipline in the four crucial and interrelated fields of sociocultural, biological, linguistic, and archaic anthropology (e.g.", "archaeology).", "Anthropology in the United States continues to be deeply influenced by the Boasian tradition, especially its emphasis on culture.Margaret Mead (1901–1978)Ruth Benedict in 1937===Kroeber, Mead, and Benedict===Boas used his positions at Columbia University and the American Museum of Natural History (AMNH) to train and develop multiple generations of students.", "His first generation of students included Alfred Kroeber, Robert Lowie, Edward Sapir, and Ruth Benedict, who each produced richly detailed studies of indigenous North American cultures.", "They provided a wealth of details used to attack the theory of a single evolutionary process.", "Kroeber and Sapir's focus on Native American languages helped establish linguistics as a truly general science and free it from its historical focus on Indo-European languages.The publication of Alfred Kroeber's textbook ''Anthropology'' (1923) marked a turning point in American anthropology.", "After three decades of amassing material, Boasians felt a growing urge to generalize.", "This was most obvious in the 'Culture and Personality' studies carried out by younger Boasians such as Margaret Mead and Ruth Benedict.", "Influenced by psychoanalytic psychologists including Sigmund Freud and Carl Jung, these authors sought to understand the way that individual personalities were shaped by the wider cultural and social forces in which they grew up.Though such works as Mead's ''Coming of Age in Samoa'' (1928) and Benedict's ''The Chrysanthemum and the Sword'' (1946) remain popular with the American public, Mead and Benedict never had the impact on the discipline of anthropology that some expected.", "Boas had planned for Ruth Benedict to succeed him as chair of Columbia's anthropology department, but she was sidelined in favor of Ralph Linton, and Mead was limited to her offices at the AMNH.===Wolf, Sahlins, Mintz, and political economy===In the 1950s and mid-1960s anthropology tended increasingly to model itself after the natural sciences.", "Some anthropologists, such as Lloyd Fallers and Clifford Geertz, focused on processes of modernization by which newly independent states could develop.", "Others, such as Julian Steward and Leslie White, focused on how societies evolve and fit their ecological niche—an approach popularized by Marvin Harris.Economic anthropology as influenced by Karl Polanyi and practiced by Marshall Sahlins and George Dalton challenged standard neoclassical economics to take account of cultural and social factors and employed Marxian analysis into anthropological study.", "In England, British Social Anthropology's paradigm began to fragment as Max Gluckman and Peter Worsley experimented with Marxism and authors such as Rodney Needham and Edmund Leach incorporated Lévi-Strauss's structuralism into their work.", "Structuralism also influenced a number of developments in the 1960s and 1970s, including cognitive anthropology and componential analysis.In keeping with the times, much of anthropology became politicized through the Algerian War of Independence and opposition to the Vietnam War; Marxism became an increasingly popular theoretical approach in the discipline.", "By the 1970s the authors of volumes such as ''Reinventing Anthropology'' worried about anthropology's relevance.Since the 1980s issues of power, such as those examined in Eric Wolf's ''Europe and the People Without History'', have been central to the discipline.", "In the 1980s books like ''Anthropology and the Colonial Encounter'' pondered anthropology's ties to colonial inequality, while the immense popularity of theorists such as Antonio Gramsci and Michel Foucault moved issues of power and hegemony into the spotlight.", "Gender and sexuality became popular topics, as did the relationship between history and anthropology, influenced by Marshall Sahlins, who drew on Lévi-Strauss and Fernand Braudel to examine the relationship between symbolic meaning, sociocultural structure, and individual agency in the processes of historical transformation.", "Jean and John Comaroff produced a whole generation of anthropologists at the University of Chicago that focused on these themes.", "Also influential in these issues were Nietzsche, Heidegger, the critical theory of the Frankfurt School, Derrida and Lacan.===Geertz, Schneider, and interpretive anthropology===Many anthropologists reacted against the renewed emphasis on materialism and scientific modelling derived from Marx by emphasizing the importance of the concept of culture.", "Authors such as David Schneider, Clifford Geertz, and Marshall Sahlins developed a more fleshed-out concept of culture as a web of meaning or signification, which proved very popular within and beyond the discipline.", "Geertz was to state:Geertz's interpretive method involved what he called \"thick description\".", "The cultural symbols of rituals, political and economic action, and of kinship, are \"read\" by the anthropologist as if they are a document in a foreign language.", "The interpretation of those symbols must be re-framed for their anthropological audience, i.e.", "transformed from the \"experience-near\" but foreign concepts of the other culture, into the \"experience-distant\" theoretical concepts of the anthropologist.", "These interpretations must then be reflected back to its originators, and its adequacy as a translation fine-tuned in a repeated way, a process called the hermeneutic circle.", "Geertz applied his method in a number of areas, creating programs of study that were very productive.", "His analysis of \"religion as a cultural system\" was particularly influential outside of anthropology.", "David Schnieder's cultural analysis of American kinship has proven equally influential.", "Schneider demonstrated that the American folk-cultural emphasis on \"blood connections\" had an undue influence on anthropological kinship theories, and that kinship is not a biological characteristic, but a cultural relationship established on very different terms in different societies.Prominent British symbolic anthropologists include Victor Turner and Mary Douglas.===The post-modern turn===In the late 1980s and 1990s authors such as James Clifford pondered ethnographic authority, in particular how and why anthropological knowledge was possible and authoritative.", "They were reflecting trends in research and discourse initiated by feminists in the academy, although they excused themselves from commenting specifically on those pioneering critics.", "Nevertheless, key aspects of feminist theory and methods became ''de rigueur'' as part of the 'post-modern moment' in anthropology: Ethnographies became more interpretative and reflexive, explicitly addressing the author's methodology; cultural, gendered, and racial positioning; and their influence on the ethnographic analysis.", "This was part of a more general trend of postmodernism that was popular contemporaneously.", "Currently anthropologists pay attention to a wide variety of issues pertaining to the contemporary world, including globalization, medicine and biotechnology, indigenous rights, virtual communities, and the anthropology of industrialized societies.===Socio-cultural anthropology subfields===* Anthropology of art* Cognitive anthropology* Anthropology of development* Disability anthropology* Ecological anthropology* Economic anthropology* Feminist anthropology and anthropology of gender and sexuality* Ethnohistory and historical anthropology* Kinship and family* Legal anthropology* Multimodal anthropology* Media anthropology* Medical anthropology* Political anthropology* Political economy in anthropology* Psychological anthropology* Public anthropology* Anthropology of religion* Cyborg anthropology* Transpersonal anthropology* Urban anthropology* Visual anthropology" ], [ "Methods", "Modern cultural anthropology has its origins in, and developed in reaction to, 19th century ethnology, which involves the organized comparison of human societies.", "Scholars like E.B.", "Tylor and J.G.", "Frazer in England worked mostly with materials collected by others—usually missionaries, traders, explorers, or colonial officials—earning them the moniker of \"arm-chair anthropologists\".===Participant observation===Participant observation is one of the principal research methods of cultural anthropology.", "It relies on the assumption that the best way to understand a group of people is to interact with them closely over a long period of time.", "The method originated in the field research of social anthropologists, especially Bronislaw Malinowski in Britain, the students of Franz Boas in the United States, and in the later urban research of the Chicago School of Sociology.", "Historically, the group of people being studied was a small, non-Western society.", "However, today it may be a specific corporation, a church group, a sports team, or a small town.", "There are no restrictions as to what the subject of participant observation can be, as long as the group of people is studied intimately by the observing anthropologist over a long period of time.", "This allows the anthropologist to develop trusting relationships with the subjects of study and receive an inside perspective on the culture, which helps him or her to give a richer description when writing about the culture later.", "Observable details (like daily time allotment) and more hidden details (like taboo behavior) are more easily observed and interpreted over a longer period of time, and researchers can discover discrepancies between what participants say—and often believe—should happen (the formal system) and what actually does happen, or between different aspects of the formal system; in contrast, a one-time survey of people's answers to a set of questions might be quite consistent, but is less likely to show conflicts between different aspects of the social system or between conscious representations and behavior.Interactions between an ethnographer and a cultural informant must go both ways.", "Just as an ethnographer may be naive or curious about a culture, the members of that culture may be curious about the ethnographer.", "To establish connections that will eventually lead to a better understanding of the cultural context of a situation, an anthropologist must be open to becoming part of the group, and willing to develop meaningful relationships with its members.", "One way to do this is to find a small area of common experience between an anthropologist and their subjects, and then to expand from this common ground into the larger area of difference.", "Once a single connection has been established, it becomes easier to integrate into the community, and more likely that accurate and complete information is being shared with the anthropologist.Before participant observation can begin, an anthropologist must choose both a location and a focus of study.", "This focus may change once the anthropologist is actively observing the chosen group of people, but having an idea of what one wants to study before beginning fieldwork allows an anthropologist to spend time researching background information on their topic.", "It can also be helpful to know what previous research has been conducted in one's chosen location or on similar topics, and if the participant observation takes place in a location where the spoken language is not one the anthropologist is familiar with, they will usually also learn that language.", "This allows the anthropologist to become better established in the community.", "The lack of need for a translator makes communication more direct, and allows the anthropologist to give a richer, more contextualized representation of what they witness.", "In addition, participant observation often requires permits from governments and research institutions in the area of study, and always needs some form of funding.The majority of participant observation is based on conversation.", "This can take the form of casual, friendly dialogue, or can also be a series of more structured interviews.", "A combination of the two is often used, sometimes along with photography, mapping, artifact collection, and various other methods.", "In some cases, ethnographers also turn to structured observation, in which an anthropologist's observations are directed by a specific set of questions they are trying to answer.", "In the case of structured observation, an observer might be required to record the order of a series of events, or describe a certain part of the surrounding environment.", "While the anthropologist still makes an effort to become integrated into the group they are studying, and still participates in the events as they observe, structured observation is more directed and specific than participant observation in general.", "This helps to standardize the method of study when ethnographic data is being compared across several groups or is needed to fulfill a specific purpose, such as research for a governmental policy decision.One common criticism of participant observation is its lack of objectivity.", "Because each anthropologist has their own background and set of experiences, each individual is likely to interpret the same culture in a different way.", "Who the ethnographer is has a lot to do with what they will eventually write about a culture, because each researcher is influenced by their own perspective.", "This is considered a problem especially when anthropologists write in the ethnographic present, a present tense which makes a culture seem stuck in time, and ignores the fact that it may have interacted with other cultures or gradually evolved since the anthropologist made observations.", "To avoid this, past ethnographers have advocated for strict training, or for anthropologists working in teams.", "However, these approaches have not generally been successful, and modern ethnographers often choose to include their personal experiences and possible biases in their writing instead.Participant observation has also raised ethical questions, since an anthropologist is in control of what they report about a culture.", "In terms of representation, an anthropologist has greater power than their subjects of study, and this has drawn criticism of participant observation in general.", "Additionally, anthropologists have struggled with the effect their presence has on a culture.", "Simply by being present, a researcher causes changes in a culture, and anthropologists continue to question whether or not it is appropriate to influence the cultures they study, or possible to avoid having influence.===Ethnography===In the 20th century, most cultural and social anthropologists turned to the crafting of ethnographies.", "An ethnography is a piece of writing about a people, at a particular place and time.", "Typically, the anthropologist lives among people in another society for a period of time, simultaneously participating in and observing the social and cultural life of the group.Numerous other ethnographic techniques have resulted in ethnographic writing or details being preserved, as cultural anthropologists also curate materials, spend long hours in libraries, churches and schools poring over records, investigate graveyards, and decipher ancient scripts.", "A typical ethnography will also include information about physical geography, climate and habitat.", "It is meant to be a holistic piece of writing about the people in question, and today often includes the longest possible timeline of past events that the ethnographer can obtain through primary and secondary research.Bronisław Malinowski developed the ethnographic method, and Franz Boas taught it in the United States.", "Boas' students such as Alfred L. Kroeber, Ruth Benedict and Margaret Mead drew on his conception of culture and cultural relativism to develop cultural anthropology in the United States.", "Simultaneously, Malinowski and A.R.", "Radcliffe Brown's students were developing social anthropology in the United Kingdom.", "Whereas cultural anthropology focused on symbols and values, social anthropology focused on social groups and institutions.", "Today socio-cultural anthropologists attend to all these elements.In the early 20th century, socio-cultural anthropology developed in different forms in Europe and in the United States.", "European \"social anthropologists\" focused on observed social behaviors and on \"social structure\", that is, on relationships among social roles (for example, husband and wife, or parent and child) and social institutions (for example, religion, economy, and politics).American \"cultural anthropologists\" focused on the ways people expressed their view of themselves and their world, especially in symbolic forms, such as art and myths.", "These two approaches frequently converged and generally complemented one another.", "For example, kinship and leadership function both as symbolic systems and as social institutions.", "Today almost all socio-cultural anthropologists refer to the work of both sets of predecessors and have an equal interest in what people do and in what people say.===Cross-cultural comparison===One means by which anthropologists combat ethnocentrism is to engage in the process of cross-cultural comparison.", "It is important to test so-called \"human universals\" against the ethnographic record.", "Monogamy, for example, is frequently touted as a universal human trait, yet comparative study shows that it is not.", "The Human Relations Area Files, Inc. (HRAF) is a research agency based at Yale University.", "Since 1949, its mission has been to encourage and facilitate worldwide comparative studies of human culture, society, and behavior in the past and present.", "The name came from the Institute of Human Relations, an interdisciplinary program/building at Yale at the time.", "The Institute of Human Relations had sponsored HRAF's precursor, the ''Cross-Cultural Survey'' (see George Peter Murdock), as part of an effort to develop an integrated science of human behavior and culture.", "The two eHRAF databases on the Web are expanded and updated annually.", "''eHRAF World Cultures'' includes materials on cultures, past and present, and covers nearly 400 cultures.", "The second database, ''eHRAF Archaeology'', covers major archaeological traditions and many more sub-traditions and sites around the world.Comparison across cultures includes the industrialized (or de-industrialized) West.", "Cultures in the more traditional standard cross-cultural sample of small-scale societies are: Africa * Nama (Hottentot)* Kung (San)* Thonga* Lozi* Mbundu* Suku* Bemba* Nyakyusa (Ngonde)* Hadza* Luguru* Kikuyu* Ganda* Mbuti (Pygmies)* Nkundo (Mongo)* Banen* Tiv* Igbo* Fon* Ashanti (Twi)* Mende* Bambara* Tallensi* Massa* Azande* Otoro Nuba* Shilluk* Mao* Maasai * Wolof* Songhai* Wodaabe Fulani* Hausa* Fur* Kaffa* Konso* Somali* Amhara* Bogo* Kenuzi Nubian* Teda* Tuareg* Riffians* Egyptians (Fellah)* Hebrews* Babylonians* Rwala Bedouin* Turks* Gheg (Albanians)* Romans* Basques* Irish* Sami (Lapps)* Russians* Abkhaz* Armenians* Kurd East Eurasia * Yurak (Samoyed)* Basseri* West Punjabi* Gond* Toda* Santal* Uttar Pradesh* Burusho* Kazak* Khalka Mongols* Lolo* Lepcha* Garo* Hajong* Lakher* Burmese* Lamet* Vietnamese* Rhade* Khmer* Siamese* Semang* Nicobarese* Andamanese* Vedda* Tanala* Negeri Sembilan* Atayal* Chinese* Manchu* Koreans* Japanese* Ainu* Gilyak* Yukaghir* Chukchi Insular Pacific * Javanese (Miao)* Balinese* Iban* Badjau* Toraja* Tobelorese* Alorese* Tiwi* Aranda* Orokaiva* Kimam* Kapauku* Kwoma* Manus* New Ireland* Trobrianders* Siuai* Tikopia* Pentecost* Mbau Fijians* Ajie* Maori* Marquesans* Western Samoans* Gilbertese* Marshallese* Chuukese* Yapese* Palauans* Ifugao North America * Ingalik* Aleut* Copper Eskimo* Montagnais* Mi'kmaq* Saulteaux (Ojibwa)* Slave* Kaska (Nahane)* Eyak* Haida* Bellacoola* Twana* Yurok* Pomo* Yokuts* Northern Paiute* Klamath* Kutenai* Gros Ventres* Hidatsa* Pawnee* Omaha (Dhegiha)* Huron* Creek* Natchez* Comanche* Chiricahua* Zuni* Havasupai* Tohono O'odham* Huichol* Aztec* Popoluca South America * Quiché* Miskito (Mosquito)* Bribri (Talamanca)* Cuna* Goajiro* Haitians* Calinago* Warrau (Warao)* Yanomamo* Kalina (Caribs)* Saramacca* Munduruku* Cubeo (Tucano)* Cayapa* Jivaro* Amahuaca* Inca* Aymara* Siriono* Nambikwara* Trumai* Timbira* Tupinamba* Botocudo* Shavante* Aweikoma* Cayua (Guarani)* Lengua* Abipon* Mapuche* Tehuelche* Yaghan===Multi-sited ethnography===Ethnography dominates socio-cultural anthropology.", "Nevertheless, many contemporary socio-cultural anthropologists have rejected earlier models of ethnography as treating local cultures as bounded and isolated.", "These anthropologists continue to concern themselves with the distinct ways people in different locales experience and understand their lives, but they often argue that one cannot understand these particular ways of life solely from a local perspective; they instead combine a focus on the local with an effort to grasp larger political, economic, and cultural frameworks that impact local lived realities.", "Notable proponents of this approach include Arjun Appadurai, James Clifford, George Marcus, Sidney Mintz, Michael Taussig, Eric Wolf and Ronald Daus.A growing trend in anthropological research and analysis is the use of multi-sited ethnography, discussed in George Marcus' article, \"Ethnography In/Of the World System: the Emergence of Multi-Sited Ethnography\".", "Looking at culture as embedded in macro-constructions of a global social order, multi-sited ethnography uses traditional methodology in various locations both spatially and temporally.", "Through this methodology, greater insight can be gained when examining the impact of world-systems on local and global communities.Also emerging in multi-sited ethnography are greater interdisciplinary approaches to fieldwork, bringing in methods from cultural studies, media studies, science and technology studies, and others.", "In multi-sited ethnography, research tracks a subject across spatial and temporal boundaries.", "For example, a multi-sited ethnography may follow a \"thing\", such as a particular commodity, as it is transported through the networks of global capitalism.Multi-sited ethnography may also follow ethnic groups in diaspora, stories or rumours that appear in multiple locations and in multiple time periods, metaphors that appear in multiple ethnographic locations, or the biographies of individual people or groups as they move through space and time.", "It may also follow conflicts that transcend boundaries.", "An example of multi-sited ethnography is Nancy Scheper-Hughes' work on the international black market for the trade of human organs.", "In this research, she follows organs as they are transferred through various legal and illegal networks of capitalism, as well as the rumours and urban legends that circulate in impoverished communities about child kidnapping and organ theft.Sociocultural anthropologists have increasingly turned their investigative eye on to \"Western\" culture.", "For example, Philippe Bourgois won the Margaret Mead Award in 1997 for ''In Search of Respect'', a study of the entrepreneurs in a Harlem crack-den.", "Also growing more popular are ethnographies of professional communities, such as laboratory researchers, Wall Street investors, law firms, or information technology (IT) computer employees." ], [ "Topics", "===Kinship and family===Kinship refers to the anthropological study of the ways in which humans form and maintain relationships with one another and how those relationships operate within and define social organization.Research in kinship studies often crosses over into different anthropological subfields including medical, feminist, and public anthropology.", "This is likely due to its fundamental concepts, as articulated by linguistic anthropologist Patrick McConvell: Throughout history, kinship studies have primarily focused on the topics of marriage, descent, and procreation.", "Anthropologists have written extensively on the variations within marriage across cultures and its legitimacy as a human institution.", "There are stark differences between communities in terms of marital practice and value, leaving much room for anthropological fieldwork.", "For instance, the Nuer of Sudan and the Brahmans of Nepal practice polygyny, where one man has several marriages to two or more women.", "The Nyar of India and Nyimba of Tibet and Nepal practice polyandry, where one woman is often married to two or more men.", "The marital practice found in most cultures, however, is monogamy, where one woman is married to one man.", "Anthropologists also study different marital taboos across cultures, most commonly the incest taboo of marriage within sibling and parent-child relationships.", "It has been found that all cultures have an incest taboo to some degree, but the taboo shifts between cultures when the marriage extends beyond the nuclear family unit.There are similar foundational differences where the act of procreation is concerned.", "Although anthropologists have found that biology is acknowledged in every cultural relationship to procreation, there are differences in the ways in which cultures assess the constructs of parenthood.", "For example, in the Nuyoo municipality of Oaxaca, Mexico, it is believed that a child can have partible maternity and partible paternity.", "In this case, a child would have multiple biological mothers in the case that it is born of one woman and then breastfed by another.", "A child would have multiple biological fathers in the case that the mother had sex with multiple men, following the commonplace belief in Nuyoo culture that pregnancy must be preceded by sex with multiple men in order have the necessary accumulation of semen.====Late twentieth-century shifts in interest====In the twenty-first century, Western ideas of kinship have evolved beyond the traditional assumptions of the nuclear family, raising anthropological questions of consanguinity, lineage, and normative marital expectation.", "The shift can be traced back to the 1960s, with the reassessment of kinship's basic principles offered by Edmund Leach, Rodney Neeham, David Schneider, and others.", "Instead of relying on narrow ideas of Western normalcy, kinship studies increasingly catered to \"more ethnographic voices, human agency, intersecting power structures, and historical context\".", "The study of kinship evolved to accommodate for the fact that it cannot be separated from its institutional roots and must pay respect to the society in which it lives, including that society's contradictions, hierarchies, and individual experiences of those within it.", "This shift was progressed further by the emergence of second-wave feminism in the early 1970s, which introduced ideas of marital oppression, sexual autonomy, and domestic subordination.", "Other themes that emerged during this time included the frequent comparisons between Eastern and Western kinship systems and the increasing amount of attention paid to anthropologists' own societies, a swift turn from the focus that had traditionally been paid to largely \"foreign\", non-Western communities.Kinship studies began to gain mainstream recognition in the late 1990s with the surging popularity of feminist anthropology, particularly with its work related to biological anthropology and the intersectional critique of gender relations.", "At this time, there was the arrival of \"Third World feminism\", a movement that argued kinship studies could not examine the gender relations of developing countries in isolation and must pay respect to racial and economic nuance as well.", "This critique became relevant, for instance, in the anthropological study of Jamaica: race and class were seen as the primary obstacles to Jamaican liberation from economic imperialism, and gender as an identity was largely ignored.", "Third World feminism aimed to combat this in the early twenty-first century by promoting these categories as coexisting factors.", "In Jamaica, marriage as an institution is often substituted for a series of partners, as poor women cannot rely on regular financial contributions in a climate of economic instability.", "In addition, there is a common practice of Jamaican women artificially lightening their skin tones in order to secure economic survival.", "These anthropological findings, according to Third World feminism, cannot see gender, racial, or class differences as separate entities, and instead must acknowledge that they interact together to produce unique individual experiences.====Rise of reproductive anthropology====Kinship studies have also experienced a rise in the interest of reproductive anthropology with the advancement of assisted reproductive technologies (ARTs), including in vitro fertilization (IVF).", "These advancements have led to new dimensions of anthropological research, as they challenge the Western standard of biogenetically based kinship, relatedness, and parenthood.", "According to anthropologists Maria C. Inhorn and Daphna Birenbaum-Carmeli, \"ARTs have pluralized notions of relatedness and led to a more dynamic notion of \"kinning\" namely, kinship as a process, as something under construction, rather than a natural given\".", "With this technology, questions of kinship have emerged over the difference between biological and genetic relatedness, as gestational surrogates can provide a biological environment for the embryo while the genetic ties remain with a third party.", "If genetic, surrogate, and adoptive maternities are involved, anthropologists have acknowledged that there can be the possibility for three \"biological\" mothers to a single child.", "With ARTs, there are also anthropological questions concerning the intersections between wealth and fertility: ARTs are generally only available to those in the highest income bracket, meaning the infertile poor are inherently devalued in the system.", "There have also been issues of reproductive tourism and bodily commodification, as individuals seek economic security through hormonal stimulation and egg harvesting, which are potentially harmful procedures.", "With IVF, specifically, there have been many questions of embryotic value and the status of life, particularly as it relates to the manufacturing of stem cells, testing, and research.Current issues in kinship studies, such as adoption, have revealed and challenged the Western cultural disposition towards the genetic, \"blood\" tie.", "Western biases against single parent homes have also been explored through similar anthropological research, uncovering that a household with a single parent experiences \"greater levels of scrutiny and is routinely seen as the 'other' of the nuclear, patriarchal family\".", "The power dynamics in reproduction, when explored through a comparative analysis of \"conventional\" and \"unconventional\" families, have been used to dissect the Western assumptions of child bearing and child rearing in contemporary kinship studies.==== Critiques of kinship studies ====Kinship, as an anthropological field of inquiry, has been heavily criticized across the discipline.", "One critique is that, as its inception, the framework of kinship studies was far too structured and formulaic, relying on dense language and stringent rules.", "Another critique, explored at length by American anthropologist David Schneider, argues that kinship has been limited by its inherent Western ethnocentrism.", "Schneider proposes that kinship is not a field that can be applied cross-culturally, as the theory itself relies on European assumptions of normalcy.", "He states in the widely circulated 1984 book ''A critique of the study of kinship'' that \"Kinship has been defined by European social scientists, and European social scientists use their own folk culture as the source of many, if not all of their ways of formulating and understanding the world about them\".", "However, this critique has been challenged by the argument that it is linguistics, not cultural divergence, that has allowed for a European bias, and that the bias can be lifted by centering the methodology on fundamental human concepts.", "Polish anthropologist Anna Wierzbicka argues that \"mother\" and \"father\" are examples of such fundamental human concepts and can only be Westernized when conflated with English concepts such as \"parent\" and \"sibling\".A more recent critique of kinship studies is its solipsistic focus on privileged, Western human relations and its promotion of normative ideals of human exceptionalism.", "In ''Critical Kinship Studies'', social psychologists Elizabeth Peel and Damien Riggs argue for a move beyond this human-centered framework, opting instead to explore kinship through a \"posthumanist\" vantage point where anthropologists focus on the intersecting relationships of human animals, non-human animals, technologies and practices.===Institutional anthropology===The role of anthropology in institutions has expanded significantly since the end of the 20th century.", "Much of this development can be attributed to the rise in anthropologists working outside of academia and the increasing importance of globalization in both institutions and the field of anthropology.", "Anthropologists can be employed by institutions such as for-profit business, nonprofit organizations, and governments.", "For instance, cultural anthropologists are commonly employed by the United States federal government.The two types of institutions defined in the field of anthropology are total institutions and social institutions.", "Total institutions are places that comprehensively coordinate the actions of people within them, and examples of total institutions include prisons, convents, and hospitals.", "Social institutions, on the other hand, are constructs that regulate individuals' day-to-day lives, such as kinship, religion, and economics.", "Anthropology of institutions may analyze labor unions, businesses ranging from small enterprises to corporations, government, medical organizations, education, prisons, and financial institutions.", "Nongovernmental organizations have garnered particular interest in the field of institutional anthropology because they are capable of fulfilling roles previously ignored by governments, or previously realized by families or local groups, in an attempt to mitigate social problems.The types and methods of scholarship performed in the anthropology of institutions can take a number of forms.", "Institutional anthropologists may study the relationship between organizations or between an organization and other parts of society.", "Institutional anthropology may also focus on the inner workings of an institution, such as the relationships, hierarchies and cultures formed, and the ways that these elements are transmitted and maintained, transformed, or abandoned over time.", "Additionally, some anthropology of institutions examines the specific design of institutions and their corresponding strength.", "More specifically, anthropologists may analyze specific events within an institution, perform semiotic investigations, or analyze the mechanisms by which knowledge and culture are organized and dispersed.In all manifestations of institutional anthropology, participant observation is critical to understanding the intricacies of the way an institution works and the consequences of actions taken by individuals within it.", "Simultaneously, anthropology of institutions extends beyond examination of the commonplace involvement of individuals in institutions to discover how and why the organizational principles evolved in the manner that they did.Common considerations taken by anthropologists in studying institutions include the physical location at which a researcher places themselves, as important interactions often take place in private, and the fact that the members of an institution are often being examined in their workplace and may not have much idle time to discuss the details of their everyday endeavors.", "The ability of individuals to present the workings of an institution in a particular light or frame must additionally be taken into account when using interviews and document analysis to understand an institution, as the involvement of an anthropologist may be met with distrust when information being released to the public is not directly controlled by the institution and could potentially be damaging." ], [ "See also", "* * * * * * * * * * * * * * * * * * * * * * *" ], [ "References" ], [ "External links", "* Official website of Human Relations Area Files (HRAF) based at Yale University** A Basic Guide to Cross-Cultural Research from HRAF" ] ]

[ [ "Conversion of units" ], [ "Introduction", " '''Conversion of units''' is the conversion of the unit of measurement in which a quantity is expressed, typically through a multiplicative '''conversion factor''' that changes the unit without changing the quantity.", "This is also often loosely taken to include replacement of a quantity with a corresponding quantity that describes the same physical property.Unit conversion is often easier within a metric system such as the SI than in others, due to the system's coherence and its metric prefixes that act as power-of-10 multipliers." ], [ "Overview", "The definition and choice of units in which to express a quantity may depend on the specific situation and the intended purpose.", "This may be governed by regulation, contract, technical specifications or other published standards.", "Engineering judgment may include such factors as:* the precision and accuracy of measurement and the associated uncertainty of measurement* the statistical confidence interval or tolerance interval of the initial measurement* the number of significant figures of the measurement* the intended use of the measurement, including the engineering tolerances* historical definitions of the units and their derivatives used in old measurements; e.g., international foot vs.", "US survey foot.For some purposes, conversions from one system of units to another are needed to be exact, without increasing or decreasing the precision of the expressed quantity.", "An ''adaptive conversion'' may not produce an exactly equivalent expression.", "Nominal values are sometimes allowed and used." ], [ "Factor–label method", "The '''factor–label method''', also known as the '''unit–factor method''' or the '''unity bracket method''', is a widely used technique for unit conversions that uses the rules of algebra.The factor–label method is the sequential application of conversion factors expressed as fractions and arranged so that any dimensional unit appearing in both the numerator and denominator of any of the fractions can be cancelled out until only the desired set of dimensional units is obtained.", "For example, 10 miles per hour can be converted to metres per second by using a sequence of conversion factors as shown below:Each conversion factor is chosen based on the relationship between one of the original units and one of the desired units (or some intermediary unit), before being rearranged to create a factor that cancels out the original unit.", "For example, as \"mile\" is the numerator in the original fraction and , \"mile\" will need to be the denominator in the conversion factor.", "Dividing both sides of the equation by 1 mile yields , which when simplified results in the dimensionless .", "Because of the identity property of multiplication, multiplying any quantity (physical or not) by the dimensionless 1 does not change that quantity.", "Once this and the conversion factor for seconds per hour have been multiplied by the original fraction to cancel out the units ''mile'' and ''hour'', 10 miles per hour converts to 4.4704 metres per second.As a more complex example, the concentration of nitrogen oxides (NO''x'') in the flue gas from an industrial furnace can be converted to a mass flow rate expressed in grams per hour (g/h) of NO''x'' by using the following information as shown below:; NO''x'' concentration := 10 parts per million by volume = 10 ppmv = 10 volumes/106 volumes; NO''x'' molar mass := 46 kg/kmol = 46 g/mol; Flow rate of flue gas := 20 cubic metres per minute = 20 m3/min: The flue gas exits the furnace at 0 °C temperature and 101.325 kPa absolute pressure.", ": The molar volume of a gas at 0 °C temperature and 101.325 kPa is 22.414 m3/kmol.", ": After cancelling any dimensional units that appear both in the numerators and the denominators of the fractions in the above equation, the NO''x'' concentration of 10 ppmv converts to mass flow rate of 24.63 grams per hour.=== Checking equations that involve dimensions ===The factor–label method can also be used on any mathematical equation to check whether or not the dimensional units on the left hand side of the equation are the same as the dimensional units on the right hand side of the equation.", "Having the same units on both sides of an equation does not ensure that the equation is correct, but having different units on the two sides (when expressed in terms of base units) of an equation implies that the equation is wrong.For example, check the universal gas law equation of , when:* the pressure ''P'' is in pascals (Pa)* the volume ''V'' is in cubic metres (m3)* the amount of substance ''n'' is in moles (mol)* the universal gas constant ''R'' is 8.3145 Pa⋅m3/(mol⋅K)* the temperature ''T'' is in kelvins (K)As can be seen, when the dimensional units appearing in the numerator and denominator of the equation's right hand side are cancelled out, both sides of the equation have the same dimensional units.", "Dimensional analysis can be used as a tool to construct equations that relate non-associated physico-chemical properties.", "The equations may reveal undiscovered or overlooked properties of matter, in the form of left-over dimensions – dimensional adjusters – that can then be assigned physical significance.", "It is important to point out that such 'mathematical manipulation' is neither without prior precedent, nor without considerable scientific significance.", "Indeed, the Planck constant, a fundamental physical constant, was 'discovered' as a purely mathematical abstraction or representation that built on the Rayleigh–Jeans law for preventing the ultraviolet catastrophe.", "It was assigned and ascended to its quantum physical significance either in tandem or post mathematical dimensional adjustment – not earlier.=== Limitations ===The factor–label method can convert only unit quantities for which the units are in a linear relationship intersecting at 0 (ratio scale in Stevens's typology).", "Most conversions fit this paradigm.", "An example for which it cannot be used is the conversion between the Celsius scale and the Kelvin scale (or the Fahrenheit scale).", "Between degrees Celsius and kelvins, there is a constant difference rather than a constant ratio, while between degrees Celsius and degrees Fahrenheit there is neither a constant difference nor a constant ratio.", "There is, however, an affine transform (, rather than a linear transform ) between them.For example, the freezing point of water is 0 °C and 32 °F, and a 5 °C change is the same as a 9 °F change.", "Thus, to convert from units of Fahrenheit to units of Celsius, one subtracts 32 °F (the offset from the point of reference), divides by 9 °F and multiplies by 5 °C (scales by the ratio of units), and adds 0 °C (the offset from the point of reference).", "Reversing this yields the formula for obtaining a quantity in units of Celsius from units of Fahrenheit; one could have started with the equivalence between 100 °C and 212 °F, which yields the same formula.Hence, to convert the numerical quantity value of a temperature ''T''F in degrees Fahrenheit to a numerical quantity value ''T''C in degrees Celsius, this formula may be used:: ''T''C = (''T''F − 32) × 5/9.To convert ''T''C in degrees Celsius to ''T''F in degrees Fahrenheit, this formula may be used:: ''T''F = (''T''C × 9/5) + 32.=== Example ===Starting with:: replace the original unit with its meaning in terms of the desired unit , e.g.", "if , then:: Now and are both numerical values, so just calculate their product.Or, which is just mathematically the same thing, multiply ''Z'' by unity, the product is still ''Z'':: For example, you have an expression for a physical value ''Z'' involving the unit ''feet per second'' () and you want it in terms of the unit ''miles per hour'' ():Or as an example using the metric system, you have a value of fuel economy in the unit ''litres per 100 kilometres'' and you want it in terms of the unit ''microlitres per metre''::" ], [ "Calculation involving non-SI Units", "In the cases where non-SI units are used, the numerical calculation of a formula can be done by first working out the factor, and then plug in the numerical values of the given/known quantities.For example, in the study of Bose–Einstein condensate, atomic mass is usually given in daltons, instead of kilograms, and chemical potential is often given in the Boltzmann constant times nanokelvin.", "The condensate's healing length is given by:For a 23Na condensate with chemical potential of (the Boltzmann constant times) 128 nK, the calculation of healing length (in micrometres) can be done in two steps:=== Calculate the factor ===Assume that , this giveswhich is our factor.=== Calculate the numbers ===Now, make use of the fact that .", "With , .This method is especially useful for programming and/or making a worksheet, where input quantities are taking multiple different values; For example, with the factor calculated above, it is very easy to see that the healing length of 174Yb with chemical potential 20.3 nK is ." ], [ "Software tools", "There are many conversion tools.", "They are found in the function libraries of applications such as spreadsheets databases, in calculators, and in macro packages and plugins for many other applications such as the mathematical, scientific and technical applications.There are many standalone applications that offer the thousands of the various units with conversions.", "For example, the free software movement offers a command line utility GNU units for Linux and Windows.", "The Unified Code for Units of Measure is also a popular option." ], [ "See also", "* Conversion of units of temperature* Dimensional analysis* English units* Imperial units* International System of Units* List of conversion factors* List of metric units* Mesures usuelles* Metric prefix* Metric system* Metrication* Natural units* United States customary units* Unit of length* Units of measurement" ], [ "Notes and references", "; Notes" ], [ "External links", "* * * NIST Guide to SI Units Many conversion factors listed.", "* The Unified Code for Units of Measure* Units, Symbols, and Conversions XML Dictionary * * * \"Instruction sur les poids et mesures républicaines – déduites de la grandeur de la terre, uniformes pour toute la République, et sur les calculs relatifs à leur division décimale\" * Unicalc Live web calculator doing units conversion by dimensional analysis* Math Skills Review* A Discussion of Units* Short Guide to Unit Conversions* Canceling Units Lesson* Chapter 11: Behavior of Gases ''Chemistry: Concepts and Applications'', Denton independent school District* Air Dispersion Modeling Conversions and Formulas* www.gnu.org/software/units free program, very practical" ] ]

[ [ "City" ], [ "Introduction", "Number of people living in urban and rural areas from 1960 to 2021A '''city''' is a human settlement of a notable size.", "The term \"city\" has different meanings around the world and in some places the settlement can be very small.", "Even where the term is limited to larger settlements, there is no fixed definition of the lower boundary for their size.", "In a more narrow sense, a city can be defined as a permanent and densely settled place with administratively defined boundaries whose members work primarily on non-agricultural tasks.", "Cities generally have extensive systems for housing, transportation, sanitation, utilities, land use, production of goods, and communication.", "Their density facilitates interaction between people, government organizations, and businesses, sometimes benefiting different parties in the process, such as improving the efficiency of goods and service distribution.Historically, city dwellers have been a small proportion of humanity overall, but following two centuries of unprecedented and rapid urbanization, more than half of the world population now lives in cities, which has had profound consequences for global sustainability.", "Present-day cities usually form the core of larger metropolitan areas and urban areas—creating numerous commuters traveling toward city centres for employment, entertainment, and education.", "However, in a world of intensifying globalization, all cities are to varying degrees also connected globally beyond these regions.", "This increased influence means that cities also have significant influences on global issues, such as sustainable development, climate change, and global health.", "Because of these major influences on global issues, the international community has prioritized investment in sustainable cities through Sustainable Development Goal 11.Due to the efficiency of transportation and the smaller land consumption, dense cities hold the potential to have a smaller ecological footprint per inhabitant than more sparsely populated areas.", "Therefore, compact cities are often referred to as a crucial element in fighting climate change.", "However, this concentration can also have significant negative consequences, such as forming urban heat islands, concentrating pollution, and stressing water supplies and other resources.Other important traits of cities besides population include the capital status and relative continued occupation of the city.", "For example, country capitals such as Beijing, Jakarta, Kuala Lumpur, London, Manila, Mexico City, Moscow, Nairobi, New Delhi, Paris, Rome, Seoul, Singapore, Tokyo, and Washington, D.C. reflect the identity and apex of their respective nations.", "Some historic capitals, such as Istanbul, Yogyakarta, and Xi'an, maintain their reflection of cultural identity even without modern capital status.", "Religious holy sites offer another example of capital status within a religion; examples include Jerusalem, Mecca, Varanasi, Ayodhya, Haridwar, and Prayagraj." ], [ "Meaning", "Palitana represents the city's symbolic role of devotion to the Jain temples.A city can be distinguished from other human settlements by its relatively great size, but also by its functions and its special symbolic status, which may be conferred by a central authority.", "The term can also refer either to the physical streets and buildings of the city or to the collection of people who dwell there and can be used in a general sense to mean urban rather than rural territory.National censuses use a variety of definitions – invoking factors such as population, population density, number of dwellings, economic function, and infrastructure – to classify populations as urban.", "Typical working definitions for small-city populations start at around 100,000 people.", "Common population definitions for an urban area (city or town) range between 1,500 and 50,000 people, with most U.S. states using a minimum between 1,500 and 5,000 inhabitants.", "Some jurisdictions set no such minima.", "In the United Kingdom, city status is awarded by the Crown and then remains permanent.", "(Historically, the qualifying factor was the presence of a cathedral, resulting in some very small cities such as Wells, with a population of 12,000 , and St Davids, with a population of 1,841 .)", "According to the \"functional definition\", a city is not distinguished by size alone, but also by the role it plays within a larger political context.", "Cities serve as administrative, commercial, religious, and cultural hubs for their larger surrounding areas.The presence of a literate elite is often associated with cities because of the cultural diversities present in a city.", "A typical city has professional administrators, regulations, and some form of taxation (food and other necessities or means to trade for them) to support the government workers.", "(This arrangement contrasts with the more typically horizontal relationships in a tribe or village accomplishing common goals through informal agreements between neighbors, or the leadership of a chief.)", "The governments may be based on heredity, religion, military power, work systems such as canal-building, food distribution, land-ownership, agriculture, commerce, manufacturing, finance, or a combination of these.", "Societies that live in cities are often called civilizations.The ''degree of urbanization'' is a modern metric to help define what comprises a city: \"a population of at least 50,000 inhabitants in contiguous dense grid cells (>1,500 inhabitants per square kilometer)\".", "This metric was \"devised over years by the European Commission, OECD, World Bank and others, and endorsed in March 2021 by the United Nations ... largely for the purpose of international statistical comparison\"." ], [ "Etymology", "The word ''city'' and the related ''civilization'' come from the Latin root ''civitas'', originally meaning 'citizenship' or 'community member' and eventually coming to correspond with ''urbs'', meaning 'city' in a more physical sense.", "The Roman ''civitas'' was closely linked with the Greek ''polis''—another common root appearing in English words such as ''metropolis''.In toponymic terminology, names of individual cities and towns are called ''astionyms'' (from Ancient Greek ἄστυ 'city or town' and ὄνομα 'name')." ], [ "Geography", "Urban geography deals both with cities in their larger context and with their internal structure.", "Cities are estimated to cover about 3% of the land surface of the Earth.=== Site ===Downtown Pittsburgh at the confluence of the Monongahela and Allegheny rivers, which flow into the Ohio RiverTown siting has varied through history according to natural, technological, economic, and military contexts.", "Access to water has long been a major factor in city placement and growth, and despite exceptions enabled by the advent of rail transport in the nineteenth century, through the present most of the world's urban population lives near the coast or on a river.Urban areas as a rule cannot produce their own food and therefore must develop some relationship with a hinterland that sustains them.", "Only in special cases such as mining towns which play a vital role in long-distance trade, are cities disconnected from the countryside which feeds them.", "Thus, centrality within a productive region influences siting, as economic forces would, in theory, favor the creation of marketplaces in optimal mutually reachable locations.=== Center ===Kluuvi, a city centre in Helsinki, FinlandThe vast majority of cities have a central area containing buildings with special economic, political, and religious significance.", "Archaeologists refer to this area by the Greek term temenos or if fortified as a citadel.", "These spaces historically reflect and amplify the city's centrality and importance to its wider sphere of influence.", "Today cities have a city center or downtown, sometimes coincident with a central business district.=== Public space ===Trafalgar Square, a public meeting place in central London Cities typically have public spaces where anyone can go.", "These include privately owned spaces open to the public as well as forms of public land such as public domain and the commons.", "Western philosophy since the time of the Greek agora has considered physical public space as the substrate of the symbolic public sphere.", "Public art adorns (or disfigures) public spaces.", "Parks and other natural sites within cities provide residents with relief from the hardness and regularity of typical built environments.", "Urban green spaces are another component of public space that provides the benefit of mitigating the urban heat island effect, especially in cities that are in warmer climates.", "These spaces prevent carbon imbalances, extreme habitat losses, electricity and water consumption, and human health risks.=== Internal structure ===The L'Enfant Plan for Washington, D.C. combines a utilitarian grid pattern with diagonal avenues and a symbolic focus on monumental architectureThe urban structure generally follows one or more basic patterns: geomorphic, radial, concentric, rectilinear, and curvilinear.", "The physical environment generally constrains the form in which a city is built.", "If located on a mountainside, urban structures may rely on terraces and winding roads.", "It may be adapted to its means of subsistence (e.g.", "agriculture or fishing).", "And it may be set up for optimal defense given the surrounding landscape.", "Beyond these \"geomorphic\" features, cities can develop internal patterns, due to natural growth or to city planning.In a radial structure, main roads converge on a central point.", "This form could evolve from successive growth over a long time, with concentric traces of town walls and citadels marking older city boundaries.", "In more recent history, such forms were supplemented by ring roads moving traffic around the outskirts of a town.", "Dutch cities such as Amsterdam and Haarlem are structured as a central square surrounded by concentric canals marking every expansion.", "In cities such as Moscow, this pattern is still clearly visible.A system of rectilinear city streets and land plots, known as the grid plan, has been used for millennia in Asia, Europe, and the Americas.", "The Indus Valley civilization built Mohenjo-Daro, Harappa, and other cities on a grid pattern, using ancient principles described by Kautilya, and aligned with the compass points.", "The ancient Greek city of Priene exemplifies a grid plan with specialized districts used across the Hellenistic Mediterranean.=== Urban areas ===Aerial view of the Gush Dan metropolitan area in Israel, showing the geometrically planned city of Tel Aviv (upper left), Givatayim to the east, and some of Bat Yam to the southThe urban-type settlement extends far beyond the traditional boundaries of the city proper in a form of development sometimes described critically as urban sprawl.", "Decentralization and dispersal of city functions (commercial, industrial, residential, cultural, political) has transformed the very meaning of the term and has challenged geographers seeking to classify territories according to an urban-rural binary.Metropolitan areas include suburbs and exurbs organized around the needs of commuters, and sometimes edge cities characterized by a degree of economic and political independence.", "(In the US these are grouped into metropolitan statistical areas for purposes of demography and marketing.)", "Some cities are now part of a continuous urban landscape called urban agglomeration, conurbation, or megalopolis (exemplified by the BosWash corridor of the Northeastern United States.)" ], [ "History", "An arch from the ancient Sumerian city Ur, which flourished in the third millennium BC, can be seen at present-day Tell el-Mukayyar in Iraq.Mohenjo-daro, a city of the Indus Valley civilization in Pakistan, which was rebuilt six or more times, using bricks of standard size, and adhering to the same grid layout—also in the third millennium BCAerial view of what was once downtown Teotihuacan showing the Pyramid of the Sun, Pyramid of the Moon, and the processional avenue serving as the spine of the city's street systemThe emergence of cities from proto-urban settlements, such as Çatalhöyük, is a non-linear development that demonstrates the varied experiences of early urbanization.The cities of Jericho, Aleppo, Faiyum, Yerevan, Athens, Matera, Damascus, and Argos are among those laying claim to the longest continual inhabitation.Cities, characterized by population density, symbolic function, and urban planning, have existed for thousands of years.", "In the conventional view, civilization and the city were both followed by the development of agriculture, which enabled the production of surplus food and thus a social division of labor (with concomitant social stratification) and trade.", "Early cities often featured granaries, sometimes within a temple.", "A minority viewpoint considers that cities may have arisen without agriculture, due to alternative means of subsistence (fishing), to use as communal seasonal shelters, to their value as bases for defensive and offensive military organization, or to their inherent economic function.", "Cities played a crucial role in the establishment of political power over an area, and ancient leaders such as Alexander the Great founded and created them with zeal.=== Ancient times ===A recreation of Ancient Rome, the first city in the world to reach one million inhabitantsJericho and Çatalhöyük, dated to the eighth millennium BC, are among the earliest proto-cities known to archaeologists.", "However, the Mesopotamian city of Uruk from the mid-fourth millennium BC (ancient Iraq) is considered by most archaeologists to be the first true city, innovating many characteristics for cities to follow, with its name attributed to the Uruk period.In the fourth and third millennium BC, complex civilizations flourished in the river valleys of Mesopotamia, India, China, and Egypt.", "Excavations in these areas have found the ruins of cities geared variously towards trade, politics, or religion.", "Some had large, dense populations, but others carried out urban activities in the realms of politics or religion without having large associated populations.Among the early Old World cities, Mohenjo-Daro of the Indus Valley civilization in present-day Pakistan, existing from about 2600 BC, was one of the largest, with a population of 50,000 or more and a sophisticated sanitation system.", "China's planned cities were constructed according to sacred principles to act as celestial microcosms.The Ancient Egyptian cities known physically by archaeologists are not extensive.", "They include (known by their Arab names) El Lahun, a workers' town associated with the pyramid of Senusret II, and the religious city Amarna built by Akhenaten and abandoned.", "These sites appear planned in a highly regimented and stratified fashion, with a minimalistic grid of rooms for the workers and increasingly more elaborate housing available for higher classes.In Mesopotamia, the civilization of Sumer, followed by Assyria and Babylon, gave rise to numerous cities, governed by kings and fostered multiple languages written in cuneiform.", "The Phoenician trading empire, flourishing around the turn of the first millennium BC, encompassed numerous cities extending from Tyre, Cydon, and Byblos to Carthage and Cádiz.In the following centuries, independent city-states of Greece, especially Athens, developed the ''polis'', an association of male landowning citizens who collectively constituted the city.", "The agora, meaning \"gathering place\" or \"assembly\", was the center of the athletic, artistic, spiritual, and political life of the polis.", "Rome was the first city that surpassed one million inhabitants.", "Under the authority of its empire, Rome transformed and founded many cities (), and with them brought its principles of urban architecture, design, and society.In the ancient Americas, early urban traditions developed in the Andes and Mesoamerica.", "In the Andes, the first urban centers developed in the Norte Chico civilization, Chavin and Moche cultures, followed by major cities in the Huari, Chimu, and Inca cultures.", "The Norte Chico civilization included as many as 30 major population centers in what is now the Norte Chico region of north-central coastal Peru.", "It is the oldest known civilization in the Americas, flourishing between the 30th and 18th centuries BC.", "Mesoamerica saw the rise of early urbanism in several cultural regions, beginning with the Olmec and spreading to the Preclassic Maya, the Zapotec of Oaxaca, and Teotihuacan in central Mexico.", "Later cultures such as the Aztec, Andean civilizations, Mayan, Mississippians, and Pueblo peoples drew on these earlier urban traditions.", "Many of their ancient cities continue to be inhabited, including major metropolitan cities such as Mexico City, in the same location as Tenochtitlan; while ancient continuously inhabited Pueblos are near modern urban areas in New Mexico, such as Acoma Pueblo near the Albuquerque metropolitan area and Taos Pueblo near Taos; while others like Lima are located nearby ancient Peruvian sites such as Pachacamac.Jenné-Jeno, located in present-day Mali and dating to the third century BC, lacked monumental architecture and a distinctive elite social class—but nevertheless had specialized production and relations with a hinterland.", "Pre-Arabic trade contacts probably existed between Jenné-Jeno and North Africa.", "Other early urban centers in sub-Saharan Africa, dated to around 500 AD, include Awdaghust, Kumbi-Saleh the ancient capital of Ghana, and Maranda a center located on a trade route between Egypt and Gao.===Middle Ages===Vyborg in Leningrad Oblast has existed since the 13th century.Old town of Utrecht, NetherlandsFree imperial cities of the Holy Roman Empire in 1648A map of Haarlem in the Netherlands, created around 1550, shows the city completely surrounded by a city wall and defensive canal, with its square shape inspired by the shape of Jerusalem.In the remnants of the Roman Empire, cities of late antiquity gained independence but soon lost population and importance.", "The locus of power in the West shifted to Constantinople and to the ascendant Islamic civilization with its major cities Baghdad, Cairo, and Córdoba.", "From the 9th through the end of the 12th century, Constantinople, the capital of the Eastern Roman Empire, was the largest and wealthiest city in Europe, with a population approaching 1 million.", "The Ottoman Empire gradually gained control over many cities in the Mediterranean area, including Constantinople in 1453.In the Holy Roman Empire, beginning in the 12th century, free imperial cities such as Nuremberg, Strasbourg, Frankfurt, Basel, Zürich, and Nijmegen became a privileged elite among towns having won self-governance from their local lord or having been granted self-governance by the emperor and being placed under his immediate protection.", "By 1480, these cities, as far as still part of the empire, became part of the Imperial Estates governing the empire with the emperor through the Imperial Diet.By the 13th and 14th centuries, some cities become powerful states, taking surrounding areas under their control or establishing extensive maritime empires.", "In Italy, medieval communes developed into city-states including the Republic of Venice and the Republic of Genoa.", "In Northern Europe, cities including Lübeck and Bruges formed the Hanseatic League for collective defense and commerce.", "Their power was later challenged and eclipsed by the Dutch commercial cities of Ghent, Ypres, and Amsterdam.", "Similar phenomena existed elsewhere, as in the case of Sakai, which enjoyed considerable autonomy in late medieval Japan.In the first millennium AD, the Khmer capital of Angkor in Cambodia grew into the most extensive preindustrial settlement in the world by area, covering over 1,000 km2 and possibly supporting up to one million people.===Early modern===In the West, nation-states became the dominant unit of political organization following the Peace of Westphalia in the seventeenth century.", "Western Europe's larger capitals (London and Paris) benefited from the growth of commerce following the emergence of an Atlantic trade.", "However, most towns remained small.During the Spanish colonization of the Americas, the old Roman city concept was extensively used.", "Cities were founded in the middle of the newly conquered territories and were bound to several laws regarding administration, finances, and urbanism.===Industrial age===The growth of the modern industry from the late 18th century onward led to massive urbanization and the rise of new great cities, first in Europe and then in other regions, as new opportunities brought huge numbers of migrants from rural communities into urban areas.", "England led the way as London became the capital of a world empire and cities across the country grew in locations strategic for manufacturing.", "In the United States from 1860 to 1910, the introduction of railroads reduced transportation costs, and large manufacturing centers began to emerge, fueling migration from rural to city areas.Some industrialized cities were confronted with health challenges associated with overcrowding, occupational hazards of industry, contaminated water and air, poor sanitation, and communicable diseases such as typhoid and cholera.", "Factories and slums emerged as regular features of the urban landscape.===Post-industrial age===In the second half of the 20th century, deindustrialization (or \"economic restructuring\") in the West led to poverty, homelessness, and urban decay in formerly prosperous cities.", "America's \"Steel Belt\" became a \"Rust Belt\" and cities such as Detroit, Michigan, and Gary, Indiana began to shrink, contrary to the global trend of massive urban expansion.", "Such cities have shifted with varying success into the service economy and public-private partnerships, with concomitant gentrification, uneven revitalization efforts, and selective cultural development.", "Under the Great Leap Forward and subsequent five-year plans continuing today, China has undergone concomitant urbanization and industrialization and become the world's leading manufacturer.Amidst these economic changes, high technology and instantaneous telecommunication enable select cities to become centers of the knowledge economy.", "A new smart city paradigm, supported by institutions such as the RAND Corporation and IBM, is bringing computerized surveillance, data analysis, and governance to bear on cities and city dwellers.", "Some companies are building brand-new master-planned cities from scratch on greenfield sites." ], [ "Urbanization", "Graph showing urbanization from 1950 projected to 2050Map showing urban areas with at least one million inhabitants in 2006Urbanization is the process of migration from rural to urban areas, driven by various political, economic, and cultural factors.", "Until the 18th century, an equilibrium existed between the rural agricultural population and towns featuring markets and small-scale manufacturing.", "With the agricultural and industrial revolutions urban population began its unprecedented growth, both through migration and demographic expansion.", "In England, the proportion of the population living in cities jumped from 17% in 1801 to 72% in 1891.In 1900, 15% of the world's population lived in cities.", "The cultural appeal of cities also plays a role in attracting residents.Urbanization rapidly spread across Europe and the Americas and since the 1950s has taken hold in Asia and Africa as well.", "The Population Division of the United Nations Department of Economic and Social Affairs reported in 2014 that for the first time, more than half of the world population lives in cities.Latin America is the most urban continent, with four-fifths` of its population living in cities, including one-fifth of the population said to live in shantytowns (favelas, poblaciones callampas, etc.).", "Batam, Indonesia, Mogadishu, Somalia, Xiamen, China, and Niamey, Niger, are considered among the world's fastest-growing cities, with annual growth rates of 5–8%.", "In general, the more developed countries of the \"Global North\" remain more urbanized than the less developed countries of the \"Global South\"—but the difference continues to shrink because urbanization is happening faster in the latter group.", "Asia is home to by far the greatest absolute number of city-dwellers: over two billion and counting.", "The UN predicts an additional 2.5 billion city dwellers (and 300 million fewer country dwellers) worldwide by 2050, with 90% of urban population expansion occurring in Asia and Africa.Megacities, cities with populations in the multi-millions, have proliferated into the dozens, arising especially in Asia, Africa, and Latin America.", "Economic globalization fuels the growth of these cities, as new torrents of foreign capital arrange for rapid industrialization, as well as the relocation of major businesses from Europe and North America, attracting immigrants from near and far.", "A deep gulf divides the rich and poor in these cities, with usually contain a super-wealthy elite living in gated communities and large masses of people living in substandard housing with inadequate infrastructure and otherwise poor conditions.Cities around the world have expanded physically as they grow in population, with increases in their surface extent, with the creation of high-rise buildings for residential and commercial use, and with development underground.Urbanization can create rapid demand for water resources management, as formerly good sources of freshwater become overused and polluted, and the volume of sewage begins to exceed manageable levels." ], [ "Government", "The city council of Tehran meets in September 2015The local government of cities takes different forms including prominently the municipality (especially in England, in the United States, India, and other British colonies; legally, the municipal corporation; ''municipio'' in Spain and Portugal, and, along with ''municipalidad'', in most former parts of the Spanish and Portuguese empires) and the ''commune'' (in France and Chile; or ''comune'' in Italy).The chief official of the city has the title of mayor.", "Whatever their true degree of political authority, the mayor typically acts as the figurehead or personification of their city.Legal conflicts and issues arise more frequently in cities than elsewhere due to the bare fact of their greater density.", "Modern city governments thoroughly regulate everyday life in many dimensions, including public and personal health, transport, burial, resource use and extraction, recreation, and the nature and use of buildings.", "Technologies, techniques, and laws governing these areas—developed in cities—have become ubiquitous in many areas.Municipal officials may be appointed from a higher level of government or elected locally.=== Municipal services ===The Dublin Fire Brigade in Dublin, Ireland, extinguishing a severe fire at a hardware store in 1970Cities typically provide municipal services such as education, through school systems; policing, through police departments; and firefighting, through fire departments; as well as the city's basic infrastructure.", "These are provided more or less routinely, in a more or less equal fashion.", "Responsibility for administration usually falls on the city government, but some services may be operated by a higher level of government, while others may be privately run.", "Armies may assume responsibility for policing cities in states of domestic turmoil such as America's King assassination riots of 1968.=== Finance ===The traditional basis for municipal finance is local property tax levied on real estate within the city.", "Local government can also collect revenue for services, or by leasing land that it owns.", "However, financing municipal services, as well as urban renewal and other development projects, is a perennial problem, which cities address through appeals to higher governments, arrangements with the private sector, and techniques such as privatization (selling services into the private sector), corporatization (formation of quasi-private municipally-owned corporations), and financialization (packaging city assets into tradeable financial public contracts and other related rights).", "This situation has become acute in deindustrialized cities and in cases where businesses and wealthier citizens have moved outside of city limits and therefore beyond the reach of taxation.", "Cities in search of ready cash increasingly resort to the municipal bond, essentially a loan with interest and a repayment date.", "City governments have also begun to use tax increment financing, in which a development project is financed by loans based on future tax revenues which it is expected to yield.", "Under these circumstances, creditors and consequently city governments place a high importance on city credit ratings.=== Governance ===The Ripon Building, the headquarters of Greater Chennai Corporation in Chennai, is one of the oldest city governing corporations in Asia.", "Governance includes government but refers to a wider domain of social control functions implemented by many actors including non-governmental organizations.", "The impact of globalization and the role of multinational corporations in local governments worldwide, has led to a shift in perspective on urban governance, away from the \"urban regime theory\" in which a coalition of local interests functionally govern, toward a theory of outside economic control, widely associated in academics with the philosophy of neoliberalism.", "In the neoliberal model of governance, public utilities are privatized, the industry is deregulated, and corporations gain the status of governing actors—as indicated by the power they wield in public-private partnerships and over business improvement districts, and in the expectation of self-regulation through corporate social responsibility.", "The biggest investors and real estate developers act as the city's de facto urban planners.The related concept of good governance places more emphasis on the state, with the purpose of assessing urban governments for their suitability for development assistance.", "The concepts of governance and good governance are especially invoked in emergent megacities, where international organizations consider existing governments inadequate for their large populations.=== Urban planning ===La Plata in Argentina is based on a perfect square with 5196-meter sides, and was designed in the 1880s as the new capital of Buenos Aires Province.Urban planning, the application of forethought to city design, involves optimizing land use, transportation, utilities, and other basic systems, in order to achieve certain objectives.", "Urban planners and scholars have proposed overlapping theories as ideals for how plans should be formed.", "Planning tools, beyond the original design of the city itself, include public capital investment in infrastructure and land-use controls such as zoning.", "The continuous process of comprehensive planning involves identifying general objectives as well as collecting data to evaluate progress and inform future decisions.Government is legally the final authority on planning but in practice, the process involves both public and private elements.", "The legal principle of eminent domain is used by the government to divest citizens of their property in cases where its use is required for a project.", "Planning often involves tradeoffs—decisions in which some stand to gain and some to lose—and thus is closely connected to the prevailing political situation.The history of urban planning dates to some of the earliest known cities, especially in the Indus Valley and Mesoamerican civilizations, which built their cities on grids and apparently zoned different areas for different purposes.", "The effects of planning, ubiquitous in today's world, can be seen most clearly in the layout of planned communities, fully designed prior to construction, often with consideration for interlocking physical, economic, and cultural systems." ], [ "Society", "=== Social structure ===Urban society is typically stratified.", "Spatially, cities are formally or informally segregated along ethnic, economic, and racial lines.", "People living relatively close together may live, work, and play in separate areas, and associate with different people, forming ethnic or lifestyle enclaves or, in areas of concentrated poverty, ghettoes.", "While in the US and elsewhere poverty became associated with the inner city, in France it has become associated with the ''banlieues'', areas of urban development that surround the city proper.", "Meanwhile, across Europe and North America, the racially white majority is empirically the most segregated group.", "Suburbs in the West, and, increasingly, gated communities and other forms of \"privatopia\" around the world, allow local elites to self-segregate into secure and exclusive neighborhoods.Landless urban workers, contrasted with peasants and known as the proletariat, form a growing stratum of society in the age of urbanization.", "In Marxist doctrine, the proletariat will inevitably revolt against the bourgeoisie as their ranks swell with disenfranchised and disaffected people lacking all stake in the status quo.", "The global urban proletariat of today, however, generally lacks the status of factory workers which in the nineteenth century provided access to the means of production.=== Economics ===Clusters of skyscrapers in Xinyi Planning District, the centre of commerce and finance of Taipei, the capital of TaiwanHistorically, cities rely on rural areas for intensive farming to yield surplus crops, in exchange for which they provide money, political administration, manufactured goods, and culture.", "Urban economics tends to analyze larger agglomerations, stretching beyond city limits, in order to reach a more complete understanding of the local labor market.As hubs of trade, cities have long been home to retail commerce and consumption through the interface of shopping.", "In the 20th century, department stores using new techniques of advertising, public relations, decoration, and design, transformed urban shopping areas into fantasy worlds encouraging self-expression and escape through consumerism.In general, the density of cities expedites commerce and facilitates knowledge spillovers, helping people and firms exchange information and generate new ideas.", "A thicker labor market allows for better skill matching between firms and individuals.", "Population density enables also sharing of common infrastructure and production facilities; however, in very dense cities, increased crowding and waiting times may lead to some negative effects.Although manufacturing fueled the growth of cities, many now rely on a tertiary or service economy.", "The services in question range from tourism, hospitality, entertainment, and housekeeping to grey-collar work in law, financial consulting, and administration.According to a scientific model of cities by Professor Geoffrey West, with the doubling of a city's size, salaries per capita will generally increase by 15%.=== Culture and communications ===Paris is one of the best-known cities in the world.Nepalese dancers at Edmonton Heritage Festival, in Alberta, Canada, an example of the cultural diversity of a cityCities are typically hubs for education and the arts, supporting universities, museums, temples, and other cultural institutions.", "They feature impressive displays of architecture ranging from small to enormous and ornate to brutal; skyscrapers, providing thousands of offices or homes within a small footprint, and visible from miles away, have become iconic urban features.", "Cultural elites tend to live in cities, bound together by shared cultural capital, and themselves play some role in governance.", "By virtue of their status as centers of culture and literacy, cities can be described as the locus of civilization, human history, and social change.Density makes for effective mass communication and transmission of news, through heralds, printed proclamations, newspapers, and digital media.", "These communication networks, though still using cities as hubs, penetrate extensively into all populated areas.", "In the age of rapid communication and transportation, commentators have described urban culture as nearly ubiquitous or as no longer meaningful.Today, a city's promotion of its cultural activities dovetails with place branding and city marketing, public diplomacy techniques used to inform development strategy; attract businesses, investors, residents, and tourists; and to create shared identity and sense of place within the metropolitan area.", "Physical inscriptions, plaques, and monuments on display physically transmit a historical context for urban places.", "Some cities, such as Jerusalem, Mecca, and Rome have indelible religious status and for hundreds of years have attracted pilgrims.", "Patriotic tourists visit Agra to see the Taj Mahal, or New York City to visit the World Trade Center.", "Elvis lovers visit Memphis to pay their respects at Graceland.", "Place brands (which include place satisfaction and place loyalty) have great economic value (comparable to the value of commodity brands) because of their influence on the decision-making process of people thinking about doing business in—\"purchasing\" (the brand of)—a city.Bread and circuses among other forms of cultural appeal, attract and entertain the masses.", "Sports also play a major role in city branding and local identity formation.", "Cities go to considerable lengths in competing to host the Olympic Games, which bring global attention and tourism.", "Paris, a city known for its cultural history, is the site of the next Olympics in the summer of 2024.=== Warfare ===atomic bombing of Hiroshima on 6 August 1945 devastated the city and led to Imperial Japan's surrender and the end of World War II.Cities play a crucial strategic role in warfare due to their economic, demographic, symbolic, and political centrality.", "For the same reasons, they are targets in asymmetric warfare.", "Many cities throughout history were founded under military auspices, a great many have incorporated fortifications, and military principles continue to influence urban design.", "Indeed, war may have served as the social rationale and economic basis for the very earliest cities.Powers engaged in geopolitical conflict have established fortified settlements as part of military strategies, as in the case of garrison towns, America's Strategic Hamlet Program during the Vietnam War, and Israeli settlements in Palestine.", "While occupying the Philippines, the US Army ordered local people to concentrate in cities and towns, in order to isolate committed insurgents and battle freely against them in the countryside.During World War II, national governments on occasion declared certain cities open, effectively surrendering them to an advancing enemy in order to avoid damage and bloodshed.", "Urban warfare proved decisive, however, in the Battle of Stalingrad, where Soviet forces repulsed German occupiers, with extreme casualties and destruction.", "In an era of low-intensity conflict and rapid urbanization, cities have become sites of long-term conflict waged both by foreign occupiers and by local governments against insurgency.", "Such warfare, known as counterinsurgency, involves techniques of surveillance and psychological warfare as well as close combat, and functionally extends modern urban crime prevention, which already uses concepts such as defensible space.Although capture is the more common objective, warfare has in some cases spelled complete destruction for a city.", "Mesopotamian tablets and ruins attest to such destruction, as does the Latin motto ''Carthago delenda est''.", "Since the atomic bombings of Hiroshima and Nagasaki and throughout the Cold War, nuclear strategists continued to contemplate the use of \"counter-value\" targeting: crippling an enemy by annihilating its valuable cities, rather than aiming primarily at its military forces.=== Climate change ===" ], [ "Infrastructure", "Traffic congestion in Bandung in IndonesiaUrban infrastructure involves various physical networks and spaces necessary for transportation, water use, energy, recreation, and public functions.", "Infrastructure carries a high initial cost in fixed capital but lower marginal costs and thus positive economies of scale.", "Because of the higher barriers to entry, these networks have been classified as natural monopolies, meaning that economic logic favors control of each network by a single organization, public or private.Infrastructure in general plays a vital role in a city's capacity for economic activity and expansion, underpinning the very survival of the city's inhabitants, as well as technological, commercial, industrial, and social activities.", "Structurally, many infrastructure systems take the form of networks with redundant links and multiple pathways, so that the system as a whole continue to operate even if parts of it fail.", "The particulars of a city's infrastructure systems have historical path dependence because new development must build from what exists already.Megaprojects such as the construction of airports, power plants, and railways require large upfront investments and thus tend to require funding from the national government or the private sector.", "Privatization may also extend to all levels of infrastructure construction and maintenance.Urban infrastructure ideally serves all residents equally but in practice may prove uneven—with, in some cities, clear first-class and second-class alternatives.=== Utilities ===Aqueduct of Segovia in Segovia, SpainPublic utilities (literally, useful things with general availability) include basic and essential infrastructure networks, chiefly concerned with the supply of water, electricity, and telecommunications capability to the populace.Sanitation, necessary for good health in crowded conditions, requires water supply and waste management as well as individual hygiene.", "Urban water systems include principally a water supply network and a network (sewerage system) for sewage and stormwater.", "Historically, either local governments or private companies have administered urban water supply, with a tendency toward government water supply in the 20th century and a tendency toward private operation at the turn of the twenty-first.", "The market for private water services is dominated by two French companies, Veolia Water (formerly Vivendi) and Engie (formerly Suez), said to hold 70% of all water contracts worldwide.Modern urban life relies heavily on the energy transmitted through electricity for the operation of electric machines (from household appliances to industrial machines to now-ubiquitous electronic systems used in communications, business, and government) and for traffic lights, street lights, and indoor lighting.", "Cities rely to a lesser extent on hydrocarbon fuels such as gasoline and natural gas for transportation, heating, and cooking.", "Telecommunications infrastructure such as telephone lines and coaxial cables also traverse cities, forming dense networks for mass and point-to-point communications.=== Transportation ===Gautrain at O. R. Tambo International Airport in JohannesburgTransJakarta in Indonesia is the longest bus rapid transit system in the world.Baana, a shared-path rail trail in HelsinkiBecause cities rely on specialization and an economic system based on wage labor, their inhabitants must have the ability to regularly travel between home, work, commerce, and entertainment.", "City dwellers travel by foot or by wheel on roads and walkways, or use special rapid transit systems based on underground, overground, and elevated rail.", "Cities also rely on long-distance transportation (truck, rail, and airplane) for economic connections with other cities and rural areas.City streets historically were the domain of horses and their riders and pedestrians, who only sometimes had sidewalks and special walking areas reserved for them.", "In the West, bicycles or (velocipedes), efficient human-powered machines for short- and medium-distance travel, enjoyed a period of popularity at the beginning of the twentieth century before the rise of automobiles.", "Soon after, they gained a more lasting foothold in Asian and African cities under European influence.", "In Western cities, industrializing, expanding, and electrifying public transit systems, and especially streetcars enabled urban expansion as new residential neighborhoods sprung up along transit lines and workers rode to and from work downtown.Since the mid-20th century, cities have relied heavily on motor vehicle transportation, with major implications for their layout, environment, and aesthetics.", "(This transformation occurred most dramatically in the US—where corporate and governmental policies favored automobile transport systems—and to a lesser extent in Europe.)", "The rise of personal cars accompanied the expansion of urban economic areas into much larger metropolises, subsequently creating ubiquitous traffic issues with the accompanying construction of new highways, wider streets, and alternative walkways for pedestrians.", "However, severe traffic jams still occur regularly in cities around the world, as private car ownership and urbanization continue to increase, overwhelming existing urban street networks.The urban bus system, the world's most common form of public transport, uses a network of scheduled routes to move people through the city, alongside cars, on the roads.", "The economic function itself also became more decentralized as concentration became impractical and employers relocated to more car-friendly locations (including edge cities).", "Some cities have introduced bus rapid transit systems which include exclusive bus lanes and other methods for prioritizing bus traffic over private cars.", "Many big American cities still operate conventional public transit by rail, as exemplified by the ever-popular New York City Subway system.", "Rapid transit is widely used in Europe and has increased in Latin America and Asia.Walking and cycling (\"non-motorized transport\") enjoy increasing favor (more pedestrian zones and bike lanes) in American and Asian urban transportation planning, under the influence of such trends as the Healthy Cities movement, the drive for sustainable development, and the idea of a carfree city.", "Techniques such as road space rationing and road use charges have been introduced to limit urban car traffic." ], [ "Housing", "terrace housing in Sydney, The housing of residents presents one of the major challenges every city must face.", "Adequate housing entails not only physical shelters but also the physical systems necessary to sustain life and economic activity.Homeownership represents status and a modicum of economic security, compared to renting which may consume much of the income of low-wage urban workers.", "Homelessness, or lack of housing, is a challenge currently faced by millions of people in countries rich and poor.", "Because cities generally have higher population densities than rural areas, city dwellers are more likely to reside in apartments and less likely to live in a single-family home." ], [ "Ecology", "An urban scene in Paramaribo featuring a few plants growing amidst solid waste and rubble behind some housesAn urban heat islandSt Stephen's Green, an urban park in Dublin, IrelandUrban ecosystems, influenced as they are by the density of human buildings and activities, differ considerably from those of their rural surroundings.", "Anthropogenic buildings and waste, as well as cultivation in gardens, create physical and chemical environments which have no equivalents in the wilderness, in some cases enabling exceptional biodiversity.", "They provide homes not only for immigrant humans but also for immigrant plants, bringing about interactions between species that never previously encountered each other.", "They introduce frequent disturbances (construction, walking) to plant and animal habitats, creating opportunities for recolonization and thus favoring young ecosystems with r-selected species dominant.", "On the whole, urban ecosystems are less complex and productive than others, due to the diminished absolute amount of biological interactions.Typical urban fauna includes insects (especially ants), rodents (mice, rats), and birds, as well as cats and dogs (domesticated and feral).", "Large predators are scarce.", "However, in North America, large predators such as coyotes and other large animals like white-tailed deer persist.", "Cities generate considerable ecological footprints, locally and at longer distances, due to concentrated populations and technological activities.", "From one perspective, cities are not ecologically sustainable due to their resource needs.", "From another, proper management may be able to ameliorate a city's ill effects.", "Air pollution arises from various forms of combustion, including fireplaces, wood or coal-burning stoves, other heating systems, and internal combustion engines.", "Industrialized cities, and today third-world megacities, are notorious for veils of smog (industrial haze) that envelop them, posing a chronic threat to the health of their millions of inhabitants.", "Urban soil contains higher concentrations of heavy metals (especially lead, copper, and nickel) and has lower pH than soil in the comparable wilderness.Modern cities are known for creating their own microclimates, due to concrete, asphalt, and other artificial surfaces, which heat up in sunlight and channel rainwater into underground ducts.", "The temperature in New York City exceeds nearby rural temperatures by an average of 2–3 °C and at times 5–10 °C differences have been recorded.", "This effect varies nonlinearly with population changes (independently of the city's physical size).", "Aerial particulates increase rainfall by 5–10%.", "Thus, urban areas experience unique climates, with earlier flowering and later leaf dropping than in nearby countries.Poor and working-class people face disproportionate exposure to environmental risks (known as environmental racism when intersecting also with racial segregation).", "For example, within the urban microclimate, less-vegetated poor neighborhoods bear more of the heat (but have fewer means of coping with it).One of the main methods of improving the urban ecology is including in the cities more urban green spaces: parks, gardens, lawns, and trees.", "These areas improve the health and well-being of the human, animal, and plant populations of the cities.", "Well-maintained urban trees can provide many social, ecological, and physical benefits to the residents of the city.A study published in ''Nature's Scientific Reports'' journal in 2019 found that people who spent at least two hours per week in nature were 23 percent more likely to be satisfied with their life and were 59 percent more likely to be in good health than those who had zero exposure.", "The study used data from almost 20,000 people in the UK.", "Benefits increased for up to 300 minutes of exposure.", "The benefits are applied to men and women of all ages, as well as across different ethnicities, socioeconomic statuses, and even those with long-term illnesses and disabilities.", "People who did not get at least two hours – even if they surpassed an hour per week – did not get the benefits.", "The study is the latest addition to a compelling body of evidence for the health benefits of nature.", "Many doctors already give nature prescriptions to their patients.", "The study didn't count time spent in a person's own yard or garden as time in nature, but the majority of nature visits in the study took place within two miles of home.", "\"Even visiting local urban green spaces seems to be a good thing,\" Dr. White said in a press release.", "\"Two hours a week is hopefully a realistic target for many people, especially given that it can be spread over an entire week to get the benefit.\"" ], [ "World city system", "As the world becomes more closely linked through economics, politics, technology, and culture (a process called globalization), cities have come to play a leading role in transnational affairs, exceeding the limitations of international relations conducted by national governments.", "This phenomenon, resurgent today, can be traced back to the Silk Road, Phoenicia, and the Greek city-states, through the Hanseatic League and other alliances of cities.", "Today the information economy based on high-speed internet infrastructure enables instantaneous telecommunication around the world, effectively eliminating the distance between cities for the purposes of the international markets and other high-level elements of the world economy, as well as personal communications and mass media.=== Global city ===Stock exchanges, characteristic features of the top global cities, are interconnected hubs for capital.", "Here, a delegation from Australia visits the London Stock Exchange.A global city, also known as a world city, is a prominent centre of trade, banking, finance, innovation, and markets.", "Saskia Sassen used the term \"global city\" in her 1991 work, ''The Global City: New York, London, Tokyo'' to refer to a city's power, status, and cosmopolitanism, rather than to its size.", "Following this view of cities, it is possible to rank the world's cities hierarchically.", "Global cities form the capstone of the global hierarchy, exerting command and control through their economic and political influence.", "Global cities may have reached their status due to early transition to post-industrialism or through inertia which has enabled them to maintain their dominance from the industrial era.", "This type of ranking exemplifies an emerging discourse in which cities, considered variations on the same ideal type, ''must'' compete with each other globally to achieve prosperity.Critics of the notion point to the different realms of power and interchange.", "The term \"global city\" is heavily influenced by economic factors and, thus, may not account for places that are otherwise significant.", "Paul James, for example argues that the term is \"reductive and skewed\" in its focus on financial systems.Multinational corporations and banks make their headquarters in global cities and conduct much of their business within this context.", "American firms dominate the international markets for law and engineering and maintain branches in the biggest foreign global cities.Large cities have a great divide between populations of both ends of the financial spectrum.", "Regulations on immigration promote the exploitation of low- and high-skilled immigrant workers from poor areas.", "During employment, migrant workers may be subject to unfair working conditions, including working overtime, low wages, and lack of safety in workplaces.=== Transnational activity ===Cities increasingly participate in world political activities independently of their enclosing nation-states.", "Early examples of this phenomenon are the sister city relationship and the promotion of multi-level governance within the European Union as a technique for European integration.", "Cities including Hamburg, Prague, Amsterdam, The Hague, and City of London maintain their own embassies to the European Union at Brussels.New urban dwellers are increasingly transmigrants, keeping one foot each (through telecommunications if not travel) in their old and their new homes.=== Global governance ===Cities participate in global governance by various means including membership in global networks which transmit norms and regulations.", "At the general, global level, United Cities and Local Governments (UCLG) is a significant umbrella organization for cities; regionally and nationally, Eurocities, Asian Network of Major Cities 21, the Federation of Canadian Municipalities the National League of Cities, and the United States Conference of Mayors play similar roles.", "UCLG took responsibility for creating Agenda 21 for culture, a program for cultural policies promoting sustainable development, and has organized various conferences and reports for its furtherance.Networks have become especially prevalent in the arena of environmentalism and specifically climate change following the adoption of Agenda 21.Environmental city networks include the C40 Cities Climate Leadership Group, the United Nations Global Compact Cities Programme, the Carbon Neutral Cities Alliance (CNCA), the Covenant of Mayors and the Compact of Mayors, ICLEI – Local Governments for Sustainability, and the Transition Towns network.Cities with world political status as meeting places for advocacy groups, non-governmental organizations, lobbyists, educational institutions, intelligence agencies, military contractors, information technology firms, and other groups with a stake in world policymaking.", "They are consequently also sites for symbolic protest.", "South Africa has one of the highest rate of protests in the world.", "Pretoria, a city in South Africa had a rally where 5 thousand people took part in order to advocate for increasing wages to afford living costs.=== United Nations System ===The World Bank headquarters in Washington, D.C.The World Assembly of Mayors at the Habitat III conference in QuitoThe United Nations System has been involved in a series of events and declarations dealing with the development of cities during this period of rapid urbanization.", "* The Habitat I conference in 1976 adopted the \"Vancouver Declaration on Human Settlements\" which identifies urban management as a fundamental aspect of development and establishes various principles for maintaining urban habitats.", "* Citing the Vancouver Declaration, the UN General Assembly in December 1977 authorized the United Nations Commission Human Settlements and the HABITAT Centre for Human Settlements, intended to coordinate UN activities related to housing and settlements.", "* The 1992 Earth Summit in Rio de Janeiro resulted in a set of international agreements including Agenda 21 which establishes principles and plans for sustainable development.", "* The Habitat II conference in 1996 called for cities to play a leading role in this program, which subsequently advanced the Millennium Development Goals and Sustainable Development Goals.", "* In January 2002 the UN Commission on Human Settlements became an umbrella agency called the United Nations Human Settlements Programme or UN-Habitat, a member of the United Nations Development Group.", "* The Habitat III conference of 2016 focused on implementing these goals under the banner of a \"New Urban Agenda\".", "The four mechanisms envisioned for effecting the New Urban Agenda are (1) national policies promoting integrated sustainable development, (2) stronger urban governance, (3) long-term integrated urban and territorial planning, and (4) effective financing frameworks.", "Just before this conference, the European Union concurrently approved an \"Urban Agenda for the European Union\" known as the Pact of Amsterdam.UN-Habitat coordinates the U.N. urban agenda, working with the UN Environmental Programme, the UN Development Programme, the Office of the High Commissioner for Human Rights, the World Health Organization, and the World Bank.The World Bank, a U.N. specialized agency, has been a primary force in promoting the Habitat conferences, and since the first Habitat conference has used their declarations as a framework for issuing loans for urban infrastructure.", "The bank's structural adjustment programs contributed to urbanization in the Third World by creating incentives to move to cities.", "The World Bank and UN-Habitat in 1999 jointly established the Cities Alliance (based at the World Bank headquarters in Washington, D.C.) to guide policymaking, knowledge sharing, and grant distribution around the issue of urban poverty.", "(UN-Habitat plays an advisory role in evaluating the quality of a locality's governance.)", "The Bank's policies have tended to focus on bolstering real estate markets through credit and technical assistance.The United Nations Educational, Scientific and Cultural Organization, UNESCO has increasingly focused on cities as key sites for influencing cultural governance.", "It has developed various city networks including the International Coalition of Cities against Racism and the Creative Cities Network.", "UNESCO's capacity to select World Heritage Sites gives the organization significant influence over cultural capital, tourism, and historic preservation funding." ], [ "Representation in culture", "John Martin, depicts chaos with the Persian army occupying Babylon, symbolizing the ruin of a decadent civilization.", "The lightning striking the Babylonian ziggurat represents the Tower of Babel and God's judgment against Babylon.Cities figure prominently in traditional Western culture, appearing in the Bible in both evil and holy forms, symbolized by Babylon and Jerusalem.", "Cain and Nimrod are the first city builders in the Book of Genesis.", "In Sumerian mythology Gilgamesh built the walls of Uruk.Cities can be perceived in terms of extremes or opposites: at once liberating and oppressive, wealthy and poor, organized and chaotic.", "The name anti-urbanism refers to various types of ideological opposition to cities, whether because of their culture or their political relationship with the country.", "Such opposition may result from identification of cities with oppression and the ruling elite.", "This and other political ideologies strongly influence narratives and themes in discourse about cities.", "In turn, cities symbolize their home societies.Writers, painters, and filmmakers have produced innumerable works of art concerning the urban experience.", "Classical and medieval literature includes a genre of ''descriptiones'' which treat of city features and history.", "Modern authors such as Charles Dickens and James Joyce are famous for evocative descriptions of their home cities.", "Fritz Lang conceived the idea for his influential 1927 film ''Metropolis'' while visiting Times Square and marveling at the nighttime neon lighting.", "Other early cinematic representations of cities in the twentieth century generally depicted them as technologically efficient spaces with smoothly functioning systems of automobile transport.", "By the 1960s, however, traffic congestion began to appear in such films as ''The Fast Lady'' (1962) and ''Playtime'' (1967).Literature, film, and other forms of popular culture have supplied visions of future cities both utopian and dystopian.", "The prospect of expanding, communicating, and increasingly interdependent world cities has given rise to images such as Nylonkong (New York, London, Hong Kong) and visions of a single world-encompassing ecumenopolis." ], [ "Gallery" ], [ "See also", "* Lists of cities* List of adjectivals and demonyms for cities* Lost city* Metropolis* Compact city* Megacity* Settlement hierarchy* Urbanization* ''''''''''" ], [ "Notes" ], [ "References", "===Bibliography===* Abrahamson, Mark (2004).", "''Global Cities''.", "Oxford University Press.", "* Ashworth, G.J.", "''War and the City''.", "London & New York: Routledge, 1991..* * Bridge, Gary, and Sophie Watson, eds.", "(2000).", "''A Companion to the City''.", "Malden, MA: Blackwell, 2000/2003.", "* Brighenti, Andrea Mubi, ed.", "(2013).", "''Urban Interstices: The Aesthetics and the Politics of the In-between.''", "Farnham: Ashgate Publishing.", ".", "* Carter, Harold (1995).", "''The Study of Urban Geography''.", "4th ed.", "London: Arnold.", "* Clark, Peter (ed.)", "(2013).", "''The Oxford Handbook of Cities in World History''.", "Oxford University Press.", "* Curtis, Simon (2016).", "''Global Cities and Global Order''.", "Oxford University Press.", "* Ellul, Jacques (1970).", "''The Meaning of the City''.", "Translated by Dennis Pardee.", "Grand Rapids, Michigan: Eerdmans, 1970.; French original (written earlier, published later as): Sans feu ni lieu : Signification biblique de la Grande Ville; Paris: Gallimard, 1975.Republished 2003 with * Gupta, Joyetta, Karin Pfeffer, Hebe Verrest, & Mirjam Ros-Tonen, eds.", "(2015).", "''Geographies of Urban Governance: Advanced Theories, Methods and Practices''.", "Springer, 2015..* Hahn, Harlan, & Charles Levine (1980).", "''Urban Politics: Past, Present, & Future''.", "New York & London: Longman.", "* Hanson, Royce (ed.). ''", "Perspectives on Urban Infrastructure''.", "Committee on National Urban Policy, Commission on Behavioral and Social Sciences and Education, National Research Council.", "Washington: National Academy Press, 1984.", "* Herrschel, Tassilo & Peter Newman (2017).", "''Cities as International Actors: Urban and Regional Governance Beyond the Nation State''.", "Palgrave Macmillan (Springer Nature).", "* * Grava, Sigurd (2003).", "''Urban Transportation Systems: Choices for Communities''.", "McGraw Hill, e-book.", "* * Kaplan, David H.; James O. Wheeler; Steven R. Holloway; & Thomas W. Hodler, cartographer (2004).", "''Urban Geography''.", "John Wiley & Sons, Inc. * Kavaratzis, Mihalis, Gary Warnaby, & Gregory J. Ashworth, eds.", "(2015).", "''Rethinking Place Branding: Comprehensive Brand Development for Cities and Regions''.", "Springer.", ".", "* Kraas, Frauke, Surinder Aggarwal, Martin Coy, & Günter Mertins, eds.", "(2014).", "''Megacities: Our Global Urban Future''.", "United Nations \"International Year of Planet Earth\" book series.", "Springer.", ".", "* Latham, Alan, Derek McCormack, Kim McNamara, & Donald McNeil (2009).", "''Key Concepts in Urban Geography''.", "London: SAGE.", ".", "* Leach, William (1993).", "''Land of Desire: Merchants, Power, and the Rise of a New American Culture''.", "New York: Vintage Books (Random House), 1994..* Levy, John M. (2017).", "''Contemporary Urban Planning''.", "11th ed.", "New York: Routledge (Taylor & Francis).", "* Magnusson, Warren.", "''Politics of Urbanism: Seeing like a city''.", "London & New York: Routledge, 2011..* Marshall, John U.", "(1989).", "''The Structure of Urban Systems''.", "University of Toronto Press.", ".", "* Marzluff, John M., Eric Schulenberger, Wilfried Endlicher, Marina Alberti, Gordon Bradley, Clre Ryan, Craig ZumBrunne, & Ute Simon (2008).", "''Urban Ecology: An International Perspective on the Interaction Between Humans and Nature''.", "New York: Springer Science+Business Media.", ".", "* McQuillan, Eugene.", "''The Law of Municipal Corporations'', 3rd ed.", "1987 revised volume by Charles R.P.", "Keating, Esq.", "Wilmette, Illinois: Callaghan & Company.", "* Moholy-Nagy, Sibyl (1968).", "''Matrix of Man: An Illustrated History of Urban Environment.''", "New York: Frederick A Praeger.", "* Mumford, Lewis (1961).", "''The City in History: Its Origins, Its Transformations, and Its Prospects''.", "New York: Harcourt, Brace & World.", "* * * Paddison, Ronan, ed.", "(2001).", "''Handbook of Urban Studies''.", "London; Thousand Oaks, California; and New Delhi: Sage Publications.", ".", "* * * Rybczynski, W., ''City Life: Urban Expectations in a New World'', (1995)* Smith, Michael E. (2002) ''The Earliest Cities.", "In Urban Life: Readings in Urban Anthropology, edited by George Gmelch and Walter Zenner'', pp.", "3–19.4th ed.", "Waveland Press, Prospect Heights, IL.", "* Southall, Aidan (1998).", "''The City in Time and Space''.", "Cambridge University Press.", "* Wellman, Kath & Marcus Spiller, eds.", "(2012).", "''Urban Infrastructure: Finance and Management''.", "Chichester, UK: Wiley-Blackwell.", ".===Further reading===* Berger, Alan S., ''The City: Urban Communities and Their Problems'', Dubuque, Iowa : William C. Brown, 1978.", "* Chandler, T. ''Four Thousand Years of Urban Growth: An Historical Census''.", "Lewiston, NY: Edwin Mellen Press, 1987.", "* Geddes, Patrick, ''City Development'' (1904)* * Kemp, Roger L. '' Managing America's Cities: A Handbook for Local Government Productivity'', McFarland and Company, Inc., Publisher, Jefferson, North Carolina and London, 2007.().", "* Kemp, Roger L. ''How American Governments Work: A Handbook of City, County, Regional, State, and Federal Operations'', McFarland and Company, Inc., Publisher, Jefferson, North Carolina and London.", "().", "* Kemp, Roger L. \"City and Gown Relations: A Handbook of Best Practices\", McFarland and Company, Inc., Publisher, Jefferson, North Carolina, US, and London, (2013).", "().", "* Monti, Daniel J. Jr., ''The American City: A Social and Cultural History''.", "Oxford, England and Malden, Massachusetts: Blackwell Publishers, 1999.391 pp. .", "* Reader, John (2005) Cities.", "Vintage, New York.", "* Robson, W.A., and Regan, D.E., ed., ''Great Cities of the World'', (3d ed., 2 vol., 1972)* Smethurst, Paul (2015).", "''The Bicycle – Towards a Global History''.", "Palgrave Macmillan.", ".", "* Smith, L. Monica (2020) ''Cities: The First 6,000 Years''.", "Penguin Books.", "* Thernstrom, S., and Sennett, R., ed., ''Nineteenth-Century Cities'' (1969)* Toynbee, Arnold J.", "(ed), ''Cities of Destiny'', New York: McGraw-Hill, 1967.Pan historical/geographical essays, many images.", "Starts with \"Athens\", ends with \"The Coming World City-Ecumenopolis\".", "* Weber, Max, ''The City'', 1921.(tr.", "1958)" ], [ "External links", "* World Urbanization Prospects, Website of the United Nations Population Division (archived 10 July 2017)* Urban population (% of total) – World Bank website based on UN data.", "* Degree of urbanization (percentage of urban population in total population) by continent in 2016 – Statista, based on Population Reference Bureau data.", "* *" ] ]

[ [ "Chervil" ], [ "Introduction", "'''Chervil''' (; '''''Anthriscus cerefolium'''''), sometimes called '''French parsley''' or '''garden chervil''' (to distinguish it from similar plants also called chervil), is a delicate annual herb related to parsley.", "It was formerly called myrhis due to its volatile oil with an aroma similar to the resinous substance myrrh.", "It is commonly used to season mild-flavoured dishes and is a constituent of the French herb mixture ." ], [ "Name", "The name ''chervil'' is from Anglo-Norman, from Latin or , meaning \"leaves of joy\"; the Latin is formed, as from an Ancient Greek word ()." ], [ "Biology", "Fresh chervilA member of the Apiaceae, chervil is native to the Caucasus but was spread by the Romans through most of Europe, where it is now naturalised.", "It is also grown frequently in the United States, where it sometimes escapes cultivation.", "Such escape can be recognized, however, as garden chervil is distinguished from all other Anthriscus species growing in North America (i.e., A. caucalis and A. sylvestris) by its having lanceolate-linear bracteoles and a fruit with a relatively long beak.The plants grow to , with tripinnate leaves that may be curly.", "The small white flowers form small umbels, across.", "The fruit is about 1 cm long, oblong-ovoid with a slender, ridged beak." ], [ "Uses and impact", "===Culinary arts===Chervil is used, particularly in France, to season poultry, seafood, young spring vegetables (such as carrots), soups, and sauces.", "More delicate than parsley, it has a faint taste of liquorice or aniseed.Chervil is one of the four traditional French , along with tarragon, chives, and parsley, which are essential to French cooking.", "Unlike the more pungent, robust herbs such as thyme and rosemary, which can take prolonged cooking, the are added at the last minute, to salads, omelettes, and soups.===Chemistry===Essential oil obtained via water distillation of wild Turkish Anthriscus cerefolium was analyzed by gas chromatography - mass spectrometry identifying 4 compounds: methyl chavicol (83.10%), 1-allyl-2,4-dimethoxybenzene (15.15%), undecane (1.75%) and β-pinene (<0.01%).===Horticulture===According to some, slugs are attracted to chervil and the plant is sometimes used to bait them.===Health===Seed of chervilChervil has had various uses in folk medicine.", "It was claimed to be useful as a digestive aid, for lowering high blood pressure, and, infused with vinegar, for curing hiccups.", "Besides its digestive properties, it is used as a mild stimulant.Chervil has also been implicated in \"strimmer dermatitis\", another name for phytophotodermatitis, due to spray from weed trimmers and similar forms of contact.", "Other plants in the family Apiaceae can have similar effects." ], [ "Cultivation", "Transplanting chervil can be difficult, due to the long taproot.", "It prefers a cool and moist location; otherwise, it rapidly goes to seed (also known as bolting).", "It is usually grown as a cool-season crop, like lettuce, and should be planted in early spring and late fall or in a winter greenhouse.", "Regular harvesting of leaves also helps to prevent bolting.", "If plants bolt despite precautions, the plant can be periodically re-sown throughout the growing season, thus producing fresh plants as older plants bolt and go out of production.Chervil grows to a height of , and a width of ." ], [ "References" ], [ "Further reading", "* ****" ] ]

[ [ "Chives" ], [ "Introduction", "Chive seedsChive seedlings sprouting'''Chives''', scientific name '''''Allium schoenoprasum''''', is a species of flowering plant in the family Amaryllidaceae that produces edible leaves and flowers.", "Their close relatives include the common onions, garlic, shallot, leek, scallion, and Chinese onion.A perennial plant, it is widespread in nature across much of Europe, Asia, and North America.''A.", "schoenoprasum'' is the only species of ''Allium'' native to both the New and the Old Worlds.Chives are a commonly used herb and can be found in grocery stores or grown in home gardens.", "In culinary use, the green stalks (scapes) and the unopened, immature flower buds are diced and used as an ingredient for omelettes, fish, potatoes, soups, and many other dishes.", "The edible flowers can be used in salads.", "Chives have insect-repelling properties that can be used in gardens to control pests.The plant provides a great deal of nectar for pollinators.", "It was rated in the top 10 for most nectar production (nectar per unit cover per year) in a UK plants survey conducted by the AgriLand project which is supported by the UK Insect Pollinators Initiative." ], [ "Description", "Chives are a bulb-forming herbaceous perennial plant, growing to tall.", "The bulbs are slender, conical, long and broad, and grow in dense clusters from the roots.", "The scapes (or stems) are hollow and tubular, up to long and across, with a soft texture, although, prior to the emergence of a flower, they may appear stiffer than usual.", "The grass-like leaves, which are shorter than the scapes, are also hollow and tubular, or terete, (round in cross-section) which distinguishes it at a glance from garlic chives (''Allium tuberosum'').", "The flowers are pale purple, and star-shaped with six petals, wide, and produced in a dense inflorescence of 10–30 together; before opening, the inflorescence is surrounded by a papery bract.", "The seeds are produced in a small, three-valved capsule, maturing in summer.", "The herb flowers from April to May in the southern parts of its habitat zones and in June in the northern parts.Chives are the only species of ''Allium'' native to both the New and the Old Worlds.", "Sometimes, the plants found in North America are classified as ''A.", "schoenoprasum'' var.", "''sibiricum'', although this is disputed.", "Differences between specimens are significant.", "One example was found in northern Maine growing solitary, instead of in clumps, also exhibiting dingy grey flowers.Although chives are repulsive to insects in general, due to their sulfur compounds, their flowers attract bees, and they are at times kept to increase desired insect life." ], [ "Taxonomy", "It was formally described by the Swedish botanist Carl Linnaeus in his seminal publication ''Species Plantarum'' in 1753.The name of the species derives from the Greek σχοίνος, ''skhoínos'' (sedge or rush) and πράσον, ''práson'' (leek).", "Its English name, chives, derives from the French word ''cive'', from ''cepa'', the Latin word for onion.", "In the Middle Ages, it was known as 'rush leek'.Some subspecies have been proposed, but are not accepted by Plants of the World Online, , which sinks them into the species:*''Allium schoenoprasum'' subsp.", "''gredense'' (Rivas Goday) Rivas Mart., Fern.Gonz.", "& Sánchez Mata*''Allium schoenoprasum'' subsp.", "''latiorifolium'' (Pau) Rivas Mart., Fern.Gonz.", "& Sánchez MataVarieties have also been proposed, including ''A.", "schoenoprasum'' var.", "''sibiricum''.", "The Flora of North America notes that the species is very variable, and considers recognition of varieties as \"unsound\"." ], [ "Distribution and habitat", "Chives are native to temperate areas of Europe, Asia and North America.===Range===Illustration from the Japanese agricultural encyclopedia ''Seikei Zusetsu'' (1804)It is found in Asia within the Caucasus (in Armenia, Azerbaijan and Georgia), also in China, Iran, Iraq, Japan (within the islands of Hokkaido and Honshu), Kazakhstan, Kyrgyzstan, Mongolia, Pakistan, Russian Federation (within the krais of Kamchatka, Khabarovsk, and Primorye) Siberia and Turkey.In middle Europe, it is found within Austria, the Czech Republic, Germany, the Netherlands, Poland and Switzerland.", "In northern Europe, in Denmark, Finland, Norway, Sweden and the United Kingdom.", "In southeastern Europe, within Bulgaria, Greece, Italy and Romania.", "It is also found in southwestern Europe, in France, Portugal and Spain.In North America, it is found in Canada (within the provinces and territories of Alberta, British Columbia, Manitoba, Northwest Territories, Nova Scotia, New Brunswick, Newfoundland, Nunavut, Ontario, Prince Edward Island, Quebec, Saskatchewan and Yukon), and the United States (within the states of Alaska, Colorado, Connecticut, Idaho, Maine, Maryland, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, New Jersey, New York, Ohio, Oregon, Pennsylvania, Rhode Island, Vermont, Washington, West Virginia, Wisconsin and Wyoming)." ], [ "Uses", "=== Culinary arts ===Chives are grown for their scapes and leaves, which are used for culinary purposes as a flavoring herb, and provide a somewhat milder onion-like flavor than those of other ''Allium'' species.Chives have a wide variety of culinary uses, such as in traditional dishes in France, Sweden, and elsewhere.", "In his 1806 book ''Attempt at a Flora'' (''Försök til en flora''), Anders Jahan Retzius describes how chives are used with pancakes, soups, fish, and sandwiches.", "They are also an ingredient of the ''gräddfil'' sauce with the traditional herring dish served at Swedish midsummer celebrations.", "The flowers may also be used to garnish dishes.", "In Poland and Germany, chives are served with quark.", "Chives are one of the ''fines herbes'' of French cuisine, the others being tarragon, chervil and parsley.", "Chives can be found fresh at most markets year-round, making them readily available; they can also be dry-frozen without much impairment to the taste, giving home growers the opportunity to store large quantities harvested from their own gardens.=== Uses in plant cultivation ===Retzius also describes how farmers would plant chives between the rocks making up the borders of their flowerbeds, to keep the plants free from pests (such as Japanese beetles).", "The growing plant repels unwanted insect life, and the juice of the leaves can be used for the same purpose, as well as fighting fungal infections, mildew, and scab." ], [ "Cultivation", "Chives are cultivated both for their culinary uses and for their ornamental value; the violet flowers are often used in ornamental dry bouquets.", "The flowers are also edible and are used in salads, or used to make blossom vinegars.Chives thrive in well-drained soil, rich in organic matter, with a pH of 6–7 and full sun.", "They can be grown from seed and mature in summer, or early the following spring.", "Typically, chives need to be germinated at a temperature of 15 to 20 °C (60 to 70 °F) and kept moist.", "They can also be planted under a cloche or germinated indoors in cooler climates, then planted out later.", "After at least four weeks, the young shoots should be ready to be planted out.", "They are also easily propagated by division.In cold regions, chives die back to the underground bulbs in winter, with the new leaves appearing in early spring.", "Chives starting to look old can be cut back to about 2–5 cm.", "When harvesting, the needed number of stalks should be cut to the base.", "During the growing season, the plant continually regrows leaves, allowing for a continuous harvest.Chives are susceptible to damage by leek moth larvae, which bore into the leaves or bulbs of the plant." ], [ "History and cultural importance", "Chives have been cultivated in Europe since the Middle Ages (from the fifth until the 15th centuries), although their usage dates back 5,000 years.", "They were sometimes referred to as \"rush leeks\".It was mentioned in 80 A.D. by Marcus Valerius Martialis in his \"Epigrams\".The Romans believed chives could relieve the pain from sunburn or a sore throat.", "They believed eating chives could increase blood pressure and act as a diuretic.Romani have used chives in fortune telling.", "Bunches of dried chives hung around a house were believed to ward off disease and evil.In the 19th century, Dutch farmers fed cattle on the herb to give a different taste to their milk." ], [ "References" ], [ "External links", "* * Nutritional Information* * Mrs. Grieve's \"A Modern Herbal\" @ Botanical.com*" ] ]

[ [ "Chris Morris (satirist)" ], [ "Introduction", "'''Christopher J. Morris''' (born 15 June 1962) is an English comedian, radio presenter, actor, and filmmaker.", "Known for his deadpan, dark humour, surrealism, and controversial subject matter, he has been praised by the British Film Institute for his \"uncompromising, moralistic drive\".In the early 1990s, Morris teamed up with his radio producer Armando Iannucci to create ''On the Hour'', a satire of news programmes.", "This was expanded into a television spin off, ''The Day Today'', which launched the career of comedian Steve Coogan and has since been hailed as one of the most important satirical shows of the 1990s.", "Morris further developed the satirical news format with ''Brass Eye'', which lampooned celebrities whilst focusing on themes such as crime and drugs.", "For many, the apotheosis of Morris' career was a ''Brass Eye'' special, which dealt with the moral panic surrounding paedophilia.", "It quickly became one of the most complained-about programmes in British television history, leading the ''Daily Mail'' to describe him as \"the most loathed man on TV\".Meanwhile, Morris' postmodern sketch comedy and ambient music radio show ''Blue Jam'', which had seen controversy similar to ''Brass Eye'', helped him to gain a cult following.", "''Blue Jam'' was adapted into the TV series ''Jam'', which some hailed as \"the most radical and original television programme broadcast in years\", and he went on to win the BAFTA Award for Best Short Film after expanding a ''Blue Jam'' sketch into ''My Wrongs 8245–8249 & 117'', which starred Paddy Considine.", "This was followed by ''Nathan Barley'', a sitcom written in collaboration with a then little-known Charlie Brooker that satirised hipsters, which had low ratings but found success upon its DVD release.", "Morris followed this by joining the cast of the sitcom ''The IT Crowd'', his first project in which he did not have writing or producing input.In 2010, Morris directed his first feature-length film, ''Four Lions'', which satirised Islamic terrorism through a group of inept British Muslims.", "Reception of the film was largely positive, earning Morris his second BAFTA Film Award, this time for Outstanding Debut.", "Since 2012, he has directed four episodes of Iannucci's political comedy ''Veep'' and appeared onscreen in ''The Double'' and ''Stewart Lee's Comedy Vehicle''.", "His second feature-length film, ''The Day Shall Come'', was released in 2019." ], [ "Early life", "Christopher J. Morris was born on 15 June 1962 in Colchester, Essex, the son of Rosemary Parrington and Paul Michael Morris.", "His father was a GP.", "Morris has a large red birthmark almost completely covering the left side of his face and neck, which he disguises with makeup when acting.", "He grew up in a Victorian farmhouse in the village of Buckden, Cambridgeshire, which he described as \"very dull\".", "He has two younger brothers, including theatre director Tom Morris.", "From an early age, he was a prankster and had a passion for radio.", "From the age of 10, he was educated at the independent Jesuit boarding school Stonyhurst College in Stonyhurst, Lancashire.", "He went to study zoology at the University of Bristol, where he gained a 2:1." ], [ "Career", "===Radio===On graduating, Morris pursued a career as a musician in various bands, for which he played the bass guitar.", "He then went to work for Radio West, a local radio station in Bristol.", "He then took up a news traineeship with BBC Radio Cambridgeshire, where he took advantage of access to editing and recording equipment to create elaborate spoofs and parodies.", "He also spent time in early 1987 hosting a 2–4pm afternoon show and finally ended up presenting Saturday morning show ''I.T.", "''In July 1987, he moved on to BBC Radio Bristol to present his own show, ''No Known Cure'', broadcast on Saturday and Sunday mornings.", "The show was surreal and satirical, with odd interviews conducted with unsuspecting members of the public.", "He was fired from Bristol in 1990 after \"talking over the news bulletins and making silly noises\".", "In 1988 he also joined, from its launch, Greater London Radio (GLR).", "He presented ''The Chris Morris Show'' on GLR until 1993, when one show got suspended after a sketch was broadcast involving a child \"outing\" celebrities.In 1991, Morris joined Armando Iannucci's spoof news project ''On the Hour''.", "Broadcast on BBC Radio 4, it saw him work alongside Iannucci, Steve Coogan, Stewart Lee, Richard Herring and Rebecca Front.", "In 1992, Morris hosted Danny Baker's Radio 5 Morning Edition show for a week whilst Baker was on holiday.", "In 1994, Morris began a weekly evening show, the ''Chris Morris Music Show'', on BBC Radio 1 alongside Peter Baynham and 'man with a mobile phone' Paul Garner.", "In the shows, Morris perfected the spoof interview style that would become a central component of his ''Brass Eye'' programme.", "In the same year, Morris teamed up with Peter Cook (as Sir Arthur Streeb-Greebling) in a series of improvised conversations for BBC Radio 3 entitled ''Why Bother?", "''.===Move into television and film===In 1994, a BBC Two television series based on ''On the Hour'' was broadcast under the name ''The Day Today''.", "''The Day Today'' made a star of Morris, and marked the television debut of Steve Coogan's Alan Partridge character.", "The programme ended on a high after just one series, with Morris winning the 1994 British Comedy Award for Best Newcomer for his lead role as the Paxmanesque news anchor.In 1996, Morris appeared on the daytime programme ''The Time, The Place'', posing as an academic, Thurston Lowe, in a discussion entitled \"Are British Men Lousy Lovers?", "\", but was found out when a producer alerted the show's host, John Stapleton.In 1997, the black humour which had featured in ''On the Hour'' and ''The Day Today'' became more prominent in ''Brass Eye'', another spoof of current affairs television documentary, shown on Channel 4.All three series satirised and exaggerated issues expected of news shows.", "The second episode of ''Brass Eye,'' for example, satirised drugs and the political rhetoric surrounding them.", "To help convey the satire, Morris invented a fictional drug by the name of \"cake\".", "In the episode, British celebrities and politicians describe the supposed symptoms in detail; David Amess mentioned the fictional drug at Parliament.", "In 2001, Morris' satirized the moral panic regarding pedophilia in the most controversial episode of ''Brass Eye'', \"Paedogeddon\".", "Channel 4 apologised for the episode after receiving criticism from tabloids and around 3,000 complaints from viewers, which, at the time, was the most for an episode of British television.", "From 1997 to 1999, Morris created ''Blue Jam'' for BBC Radio 1, a surreal taboo-breaking radio show set to an ambient soundtrack.", "In 2000, this was followed by ''Jam'', a television reworking.", "Morris released a 'remix' version of this, entitled ''Jaaaaam''.In 2002, Morris ventured into film, directing the short ''My Wrongs#8245–8249 & 117'', adapted from a ''Blue Jam'' monologue about a man led astray by a sinister talking dog.", "It was the first film project of Warp Films, a branch of Warp Records.", "In 2002 it won the BAFTA for best short film.", "In 2005 Morris worked on a sitcom entitled ''Nathan Barley'', based on the character created by Charlie Brooker for his website TVGoHome (Morris had contributed to TVGoHome on occasion, under the pseudonym 'Sid Peach').", "Co-written by Brooker and Morris, the series was broadcast on Channel 4 in early 2005.===''The IT Crowd'' and ''Comedy Vehicle''===Morris appeared in ''The IT Crowd'', a Channel 4 sitcom which focuses on the information technology department of the fictional company Reynholm Industries.", "The series was written and directed by Graham Linehan (with whom Morris collaborated on ''The Day Today'', ''Brass Eye'' and ''Jam'') and produced by Ash Atalla.", "Morris played Denholm Reynholm, the eccentric managing director of the company.", "This marked the first time Morris had acted in a substantial role in a project which he has not developed himself.", "Morris' character was killed off during episode two of the second series.", "His character made a brief return in the first episode of the third series.In November 2007, Morris wrote an article for ''The Observer'' in response to Ronan Bennett's article published six days earlier in ''The Guardian''.", "Bennett's article, \"Shame on us\", accused the novelist Martin Amis of racism.", "Morris' response, \"The absurd world of Martin Amis\", was also highly critical of Amis; although he did not accede to Bennett's accusation of racism, Morris likened Amis to the Muslim cleric Abu Hamza (who was jailed for inciting racial hatred in 2006), suggesting that both men employ \"mock erudition, vitriol and decontextualised quotes from the Qu'ran\" to incite hatred.Morris served as script editor for the 2009 series ''Stewart Lee's Comedy Vehicle'', working with former colleagues Stewart Lee, Kevin Eldon and Armando Iannucci.", "He maintained this role for the second (2011) and third series (2014), also appearing as a mock interviewer dubbed the \"hostile interrogator\" in the third and fourth series.===''Four Lions'', ''Veep'', and other appearances===Morris completed his debut feature film ''Four Lions'' in late 2009, a satire based on a group of Islamist terrorists in Sheffield.It premiered at the Sundance Film Festival in January 2010 and was short-listed for the festival's World Cinema Narrative prize.", "The film (working title ''Boilerhouse'') was picked up by Film Four.", "Morris told ''The Sunday Times'' that the film sought to do for Islamic terrorism what ''Dad's Army'', the classic BBC comedy, did for the Nazis by showing them as \"scary but also ridiculous\".In 2012, Morris directed the seventh and penultimate episode of the first season of ''Veep'', an Armando Iannucci-devised American version of ''The Thick of It''.", "In 2013, he returned to direct two episodes for the second season of ''Veep'', and a further episode for season three in 2014.In 2013, Morris appeared briefly in Richard Ayoade's ''The Double'', a black comedy film based on the Fyodor Dostoyevsky novella of the same name.", "Morris had previously worked with Ayoade on ''Nathan Barley'' and ''The IT Crowd''.In February 2014, Morris made a surprise appearance at the beginning of a Stewart Lee live show, introducing the comedian with fictional anecdotes about their work together.", "The following month, Morris appeared in the third series of ''Stewart Lee's Comedy Vehicle'' as a \"hostile interrogator\", a role previously occupied by Armando Iannucci.In December 2014, it was announced that a short radio collaboration with Noel Fielding and Richard Ayoade would be broadcast on BBC Radio 6.According to Fielding, the work had been in progress since around 2006.However, in January 2015 it was decided, 'in consultation with Morris', that the project was not yet complete, and so the intended broadcast did not go ahead.===''The Day Shall Come''===A statement released by Film4 in February 2016 made reference to funding what would be Morris' second feature film.", "In November 2017 it was reported that Morris had shot the movie, starring Anna Kendrick, in the Dominican Republic but the title was not made public.", "It was later reported in January 2018 that Jim Gaffigan and Rupert Friend had joined the cast of the still-untitled film, and that the plot would revolve around an FBI hostage situation gone wrong.", "The completed film, titled ''The Day Shall Come'', had its world premiere at South by Southwest on 11 March 2019.===Music===Morris often co-writes and performs incidental music for his television shows, notably with ''Jam'' and the 'extended remix' version, ''Jaaaaam''.", "In the early 1990s Morris contributed a Pixies parody track entitled \"Motherbanger\" to a flexi-disc given away with an edition of Select music magazine.", "Morris supplied sketches for British band Saint Etienne's 1993 single \"You're in a Bad Way\" (the sketch 'Spongbake' appears at the end of the 4th track on the CD single).In 2000, he collaborated by mail with Amon Tobin to create the track \"Bad Sex\", which was released as a B-side on the Tobin single \"Slowly\".British band Stereolab's song \"Nothing to Do with Me\" from their 2001 album ''Sound-Dust'' featured various lines from Chris Morris sketches as lyrics." ], [ "Style", "Ramsey Ess of ''Vulture'' described Morris' comedy style as \"crass\" and \"shocking\", but noted an \"underlying morality\" and integrity, as well as the humor being Morris' priority." ], [ "Recognition", "In 2003, Morris was listed in ''The Observer'' as one of the 50 funniest acts in British comedy.", "In 2005, Channel 4 aired a show called ''The Comedian's Comedian'' in which foremost writers and performers of comedy ranked their 50 favourite acts.", "Morris was at number eleven.", "Morris won the BAFTA for outstanding debut with his film ''Four Lions''.", "Adeel Akhtar and Nigel Lindsay collected the award in his absence.", "Lindsay stated that Morris had sent him a text message before they collected the award reading, 'Doused in petrol, Zippo at the ready'.", "In June 2012 Morris was placed at number 16 in the Top 100 People in UK Comedy.In 2010, a biography, ''Disgusting Bliss: The Brass Eye of Chris Morris'', was published.", "Written by Lucian Randall, the book depicted Morris as \"brilliant but uncompromising\", and a \"frantic-minded perfectionist\".In November 2014, a three-hour retrospective of Morris' radio career was broadcast on BBC Radio 4 Extra under the title 'Raw Meat Radio', presented by Mary Anne Hobbs and featuring interviews with Armando Iannucci, Peter Baynham, Paul Garner, and others.===Awards===Morris won the Best TV Comedy Newcomer award from the British Comedy Awards in 1994 for his performance in ''The Day Today''.", "He has won two BAFTA awards: the BAFTA Award for Best Short Film in 2002 for ''My Wrongs #8245–8249 & 117'', and the BAFTA Award for Outstanding Debut by a British director, writer or producer in 2011 for ''Four Lions''." ], [ "Personal life", "Morris and his wife, actress-turned-literary agent Jo Unwin, live in the Brixton district of London.", "The pair met in 1984 at the Edinburgh Festival, when he was playing bass guitar for the Cambridge Footlights Revue and she was in a comedy troupe called the Millies.", "They have two sons, Charles and Frederick, both of whom were born in Lambeth in south London.", "Giving very few interviews and avoiding all social media, Morris has been described as a recluse." ], [ "Works", "===Film=== Title Year Functioned as Notes Director Writer Producer Appeared Role ''My Wrongs #8245–8249 & 117'' 2002 Rothko (voice) Short film; also composer and sound designer ''Four Lions'' 2010 Commentator on end credits (voice) ''The Double'' 2013 Workers' Services Executive ''The Day Shall Come'' 2019 ===Television=== Title Year Functioned as Notes Director Writer Producer Appeared Role ''Spitting Image'' 1984 Episode: \"#1.11\" ''Up Yer News'' 1990 ''The Day Today'' 1994 Christopher Morris / Ted Maul / Various characters 6 episodes; also creator and composer ''I'm Alan Partridge'' 1997 Peter Baxendale Thomas Episode: \"Watership Alan\" ''Brass Eye'' 1997, 2001 Christopher Morris / Ted Maul / Various characters 7 episodes; also creator and composer ''Big Train'' 1998 Narrator of Jockey Doco (voice) Episode: \"Episode #1.2\" ''Jam'' 2000 Chris / Various characters 6 episodes; also creator and composer ''Nathan Barley'' 2005 Place VO (voice) 6 episodes; also creator and composer ''The IT Crowd'' 2006–2008 Denholm Reynholm 7 episodes ''Stewart Lee's Comedy Vehicle'' 2009–2016 Interviewer Script editor ''Veep'' 2012–2014 Newsreader (voice) Directed four episodes, appeared in episode: \"Full Disclosure\"===Other===* Various works at BBC Radio Cambridgeshire (1986–1987) (presenter)* ''No Known Cure'' (July 1987 – March 1990, BBC Radio Bristol) (presenter)* ''Chris Morris'' (1988–1993, BBC GLR) (presenter)* ''Morning Edition'' (July 1990, BBC Radio 5) (guest presenter)* ''The Chris Morris Christmas Show'' (25 December 1990, BBC Radio 1)* ''On the Hour'' (1991–1992, BBC Radio 4) (co-writer, performer)* ''It's Only TV'' (September 1992, LWT) (unbroadcast pilot)* ''Why Bother?''", "(1994, BBC Radio 3) (performer, editor)* ''The Chris Morris Music Show'' (1994, BBC Radio 1) (presenter)* ''Blue Jam'' (1997–1999, BBC Radio 1) (writer, director, performer, editor)* ''Second Class Male/Time To Go'' (1999, newspaper column for ''The Observer'')* ''The Smokehammer'' (2002, website)* ''Absolute Atrocity Special'' (2002, newspaper pullout for ''The Observer'')" ], [ "References" ], [ "External links", "* * *" ] ]

[ [ "Colorado" ], [ "Introduction", "'''Colorado''' (, other variants) is a state in the Mountain West subregion of the Western United States.", "Colorado borders Wyoming to the north, Nebraska to the northeast, Kansas to the east, Oklahoma to the southeast, New Mexico to the south, Utah to the west, and meets Arizona to the southwest at the Four Corners.", "Colorado is noted for its landscape of mountains, forests, high plains, mesas, canyons, plateaus, rivers, and desert lands.", "Colorado is one of the Mountain States and is often considered to be part of the southwestern United States.", "The high plains of Colorado may be considered a part of the midwestern United States.", "It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains.", "Colorado is the eighth most extensive and 21st most populous U.S. state.", "The United States Census Bureau estimated the population of Colorado at 5,877,610 as of July 1, 2023, a 1.80% increase since the 2020 United States census.The region has been inhabited by Native Americans and their ancestors for at least 13,500 years and possibly much longer.", "The eastern edge of the Rocky Mountains was a major migration route for early peoples who spread throughout the Americas.", "In 1848, much of the Nuevo México region was annexed to the United States with the Treaty of Guadalupe Hidalgo.", "The Pike's Peak Gold Rush of 1858–1862 created an influx of settlers.", "On February 28, 1861, U.S. President James Buchanan signed an act creating the Territory of Colorado, and on August 1, 1876, President Ulysses S. Grant signed Proclamation 230 admitting Colorado to the Union as the 38th state.", "The Spanish adjective ''\"colorado\"'' means \"colored red\" or \"ruddy\".", "Colorado is nicknamed the \"Centennial State\" because it became a state one century (and four weeks) after the signing of the United States Declaration of Independence.Denver is the capital, the most populous city, and the center of the Front Range Urban Corridor.", "Colorado Springs is the second most populous city.", "Residents of the state are known as Coloradans, although the antiquated \"Coloradoan\" is occasionally used.", "Major parts of the economy include government and defense, mining, agriculture, tourism, and increasingly other kinds of manufacturing.", "With increasing temperatures and decreasing water availability, Colorado's agriculture, forestry, and tourism economies are expected to be heavily affected by climate change." ], [ "History", "The ruins of the Cliff Palace of Mesa Verde photographed by Gustaf Nordenskiöld in 1891.Great Kiva at Chimney Rock in the San Juan Mountains of Southwestern Colorado.", "It was built by the Ancient Pueblo peoples.The region that is today the State of Colorado has been inhabited by Native Americans and their Paleoamerican ancestors for at least 13,500 years and possibly more than 37,000 years.", "The eastern edge of the Rocky Mountains was a major migration route that was important to the spread of early peoples throughout the Americas.", "The Lindenmeier site in Larimer County contains artifacts dating from approximately 8720 BCE.", "The Ancient Pueblo peoples lived in the valleys and mesas of the Colorado Plateau.", "The Ute Nation inhabited the mountain valleys of the Southern Rocky Mountains and the Western Rocky Mountains, even as far east as the Front Range of the present day.", "The Apache and the Comanche also inhabited the Eastern and Southeastern parts of the state.", "In the 17th century, the Arapaho and Cheyenne moved west from the Great Lakes region to hunt across the High Plains of Colorado and Wyoming.The Spanish Empire claimed Colorado as part of Nuevo México.", "The U.S. acquired the territorial claim to the eastern Rocky Mountains with the Louisiana Purchase from France in 1803.This U.S. claim conflicted with the claim by Spain to the upper Arkansas River Basin.", "In 1806, Zebulon Pike led a U.S. Army reconnaissance expedition into the disputed region.", "Colonel Pike and his troops were arrested by Spanish cavalrymen in the San Luis Valley the following February, taken to Chihuahua, and expelled from Mexico the following July.The U.S. relinquished its claim to all land south and west of the Arkansas River and south of 42nd parallel north and west of the 100th meridian west as part of its purchase of Florida from Spain with the Adams-Onís Treaty of 1819.The treaty took effect on February 22, 1821.Having settled its border with Spain, the U.S. admitted the southeastern portion of the Territory of Missouri to the Union as the state of Missouri on August 10, 1821.The remainder of Missouri Territory, including what would become northeastern Colorado, became an unorganized territory and remained so for 33 years over the question of slavery.", "After 11 years of war, Spain finally recognized the independence of Mexico with the Treaty of Córdoba signed on August 24, 1821.Mexico eventually ratified the Adams–Onís Treaty in 1831.The Texian Revolt of 1835–36 fomented a dispute between the U.S. and Mexico which eventually erupted into the Mexican–American War in 1846.Mexico surrendered its northern territory to the U.S. with the Treaty of Guadalupe Hidalgo after the war in 1848; this included much of the western and southern areas of the current state of Colorado.Map of the Mexican Cession, with the white representing the territory the United States received from Mexico (plus land ceded to the Republic of Texas) after the Mexican–American War.", "Well over half of Colorado was received from this treaty.Most American settlers first traveled to Colorado through the Santa Fe Trail, which connected the U.S. to Santa Fe and the Camino Real de Tierra Adentro southward.", "Others were traveling overland west to the Oregon Country, the new goldfields of California, or the new Mormon settlements of the State of Deseret in the Salt Lake Valley, avoided the rugged Southern Rocky Mountains, and instead followed the North Platte River and Sweetwater River to South Pass (Wyoming), the lowest crossing of the Continental Divide between the Southern Rocky Mountains and the Central Rocky Mountains.", "In 1849, the Mormons of the Salt Lake Valley organized the extralegal State of Deseret, claiming the entire Great Basin and all lands drained by the rivers Green, Grand, and Colorado.", "The federal government of the U.S. flatly refused to recognize the new Mormon government, because it was theocratic and sanctioned plural marriage.", "Instead, the Compromise of 1850 divided the Mexican Cession and the northwestern claims of Texas into a new state and two new territories, the state of California, the Territory of New Mexico, and the Territory of Utah.", "On April 9, 1851, Mexican American settlers from the area of Taos settled the village of San Luis, then in the New Mexico Territory, later to become Colorado's first permanent Euro-American settlement.Canyons of the Ancients Visitor Center & Museum in DoloresIn 1854, Senator Stephen A. Douglas persuaded the U.S. Congress to divide the unorganized territory east of the Continental Divide into two new organized territories, the Territory of Kansas and the Territory of Nebraska, and an unorganized southern region known as the Indian territory.", "Each new territory was to decide the fate of slavery within its boundaries, but this compromise merely served to fuel animosity between free soil and pro-slavery factions.The gold seekers organized the Provisional Government of the Territory of Jefferson on August 24, 1859, but this new territory failed to secure approval from the Congress of the United States embroiled in the debate over slavery.", "The election of Abraham Lincoln for the President of the United States on November 6, 1860, led to the secession of nine southern slave states and the threat of civil war among the states.", "Seeking to augment the political power of the Union states, the Republican Party-dominated Congress quickly admitted the eastern portion of the Territory of Kansas into the Union as the free State of Kansas on January 29, 1861, leaving the western portion of the Kansas Territory, and its gold-mining areas, as unorganized territory.===Territory act===New Mexico, Utah, Kansas, and Nebraska before the creation of the Territory of ColoradoThirty days later on February 28, 1861, outgoing U.S. President James Buchanan signed an Act of Congress organizing the free Territory of Colorado.", "The original boundaries of Colorado remain unchanged except for government survey amendments.", "In 1776, Spanish priest Silvestre Vélez de Escalante recorded that Native Americans in the area knew the river as ''el Rio Colorado'' for the red-brown silt that the river carried from the mountains.", "In 1859, a U.S. Army topographic expedition led by Captain John Macomb located the confluence of the Green River with the Grand River in what is now Canyonlands National Park in Utah.", "The Macomb party designated the confluence as the source of the Colorado River.On April 12, 1861, South Carolina artillery opened fire on Fort Sumter to start the American Civil War.", "While many gold seekers held sympathies for the Confederacy, the vast majority remained fiercely loyal to the Union cause.In 1862, a force of Texas cavalry invaded the Territory of New Mexico and captured Santa Fe on March 10.The object of this Western Campaign was to seize or disrupt the gold fields of Colorado and California and to seize ports on the Pacific Ocean for the Confederacy.", "A hastily organized force of Colorado volunteers force-marched from Denver City, Colorado Territory, to Glorieta Pass, New Mexico Territory, in an attempt to block the Texans.", "On March 28, the Coloradans and local New Mexico volunteers stopped the Texans at the Battle of Glorieta Pass, destroyed their cannon and supply wagons, and dispersed 500 of their horses and mules.", "The Texans were forced to retreat to Santa Fe.", "Having lost the supplies for their campaign and finding little support in New Mexico, the Texans abandoned Santa Fe and returned to San Antonio in defeat.", "The Confederacy made no further attempts to seize the Southwestern United States.Mount of the Holy Cross, photographed by William Henry Jackson in 1874In 1864, Territorial Governor John Evans appointed the Reverend John Chivington as Colonel of the Colorado Volunteers with orders to protect white settlers from Cheyenne and Arapaho warriors who were accused of stealing cattle.", "Colonel Chivington ordered his troops to attack a band of Cheyenne and Arapaho encamped along Sand Creek.", "Chivington reported that his troops killed more than 500 warriors.", "The militia returned to Denver City in triumph, but several officers reported that the so-called battle was a blatant massacre of Indians at peace, that most of the dead were women and children, and that the bodies of the dead had been hideously mutilated and desecrated.", "Three U.S. Army inquiries condemned the action, and incoming President Andrew Johnson asked Governor Evans for his resignation, but none of the perpetrators was ever punished.", "This event is now known as the Sand Creek massacre.In the midst and aftermath of the Civil War, many discouraged prospectors returned to their homes, but a few stayed and developed mines, mills, farms, ranches, roads, and towns in Colorado Territory.", "On September 14, 1864, James Huff discovered silver near Argentine Pass, the first of many silver strikes.", "In 1867, the Union Pacific Railroad laid its tracks west to Weir, now Julesburg, in the northeast corner of the Territory.", "The Union Pacific linked up with the Central Pacific Railroad at Promontory Summit, Utah, on May 10, 1869, to form the First transcontinental railroad.", "The Denver Pacific Railway reached Denver in June of the following year, and the Kansas Pacific arrived two months later to forge the second line across the continent.", "In 1872, rich veins of silver were discovered in the San Juan Mountains on the Ute Indian reservation in southwestern Colorado.", "The Ute people were removed from the San Juans the following year.===Statehood===The Georgetown Loop of the Colorado Central Railroad as photographed by William Henry Jackson in 1899The United States Congress passed an enabling act on March 3, 1875, specifying the requirements for the Territory of Colorado to become a state.", "On August 1, 1876 (four weeks after the Centennial of the United States), U.S. President Ulysses S. Grant signed a proclamation admitting Colorado to the Union as the 38th state and earning it the moniker \"Centennial State\".The discovery of a major silver lode near Leadville in 1878 triggered the Colorado Silver Boom.", "The Sherman Silver Purchase Act of 1890 invigorated silver mining, and Colorado's last, but greatest, gold strike at Cripple Creek a few months later lured a new generation of gold seekers.", "Colorado women were granted the right to vote on November 7, 1893, making Colorado the second state to grant universal suffrage and the first one by a popular vote (of Colorado men).", "The repeal of the Sherman Silver Purchase Act in 1893 led to a staggering collapse of the mining and agricultural economy of Colorado, but the state slowly and steadily recovered.", "Between the 1880s and 1930s, Denver's floriculture industry developed into a major industry in Colorado.", "This period became known locally as the Carnation Gold Rush.===Twentieth and twenty-first centuries===Poor labor conditions and discontent among miners resulted in several major clashes between strikers and the Colorado National Guard, including the 1903–1904 Western Federation of Miners Strike and Colorado Coalfield War, the latter of which included the Ludlow massacre that killed a dozen women and children.", "Both the 1913–1914 Coalfield War and the Denver streetcar strike of 1920 resulted in federal troops intervening to end the violence.", "In 1927, the 1927-28 Colorado coal strike occurred and was ultimately successful in winning a dollar a day increase in wages.", "During it however the Columbine Mine massacre resulted in six dead strikers following a confrontation with Colorado Rangers.", "In a separate incident in Trinidad the mayor was accused of deputizing members of the KKK against the striking workers.", "More than 5,000 Colorado miners—many immigrants—are estimated to have died in accidents since records were first formally collected following an 1884 accident in Crested Butte that killed 59.In 1924, the Ku Klux Klan Colorado Realm achieved dominance in Colorado politics.", "With peak membership levels, the Second Klan levied significant control over both the local and state Democrat and Republican parties, particularly in the governor's office and city governments of Denver, Cañon City, and Durango.", "A particularly strong element of the Klan controlled the Denver Police.", "Cross burnings became semi-regular occurrences in cities such as Florence and Pueblo.", "The Klan targeted African-Americans, Catholics, Eastern European immigrants, and other non-White Protestant groups.", "Efforts by non-Klan lawmen and lawyers including Philip Van Cise lead to a rapid decline in the organization's power, with membership waning significantly by the end of the 1920s.Three 10th Mountain Division skitroopers above Camp Hale in February 1944.Colorado became the first western state to host a major political convention when the Democratic Party met in Denver in 1908.By the U.S. census in 1930, the population of Colorado first exceeded one million residents.", "Colorado suffered greatly through the Great Depression and the Dust Bowl of the 1930s, but a major wave of immigration following World War II boosted Colorado's fortune.", "Tourism became a mainstay of the state economy, and high technology became an important economic engine.", "The United States Census Bureau estimated that the population of Colorado exceeded five million in 2009.On September 11, 1957, a plutonium fire occurred at the Rocky Flats Plant, which resulted in the significant plutonium contamination of surrounding populated areas.From the 1940s and 1970s, many protest movements gained momentum in Colorado, predominantly in Denver.", "This included the Chicano Movement, a civil rights, and social movement of Mexican Americans emphasizing a Chicano identity that is widely considered to have begun in Denver.", "The National Chicano Liberation Youth Conference was held in Colorado in March 1969.In 1967, Colorado was the first state to loosen restrictions on abortion when governor John Love signed a law allowing abortions in cases of rape, incest, or threats to the woman's mental or physical health.", "Many states followed Colorado's lead in loosening abortion laws in the 1960s and 1970s.Since the late 1990s, Colorado has been the site of multiple major mass shootings, including the infamous Columbine High School massacre in 1999 which made international news, where two gunmen killed 12 students and one teacher, before committing suicide.", "The incident has since spawned many copycat incidents.", "On July 20, 2012, a gunman killed 12 people in a movie theater in Aurora.", "The state responded with tighter restrictions on firearms, including introducing a limit on magazine capacity.", "On March 22, 2021, a gunman killed 10 people, including a police officer, in a King Soopers supermarket in Boulder.", "In an instance of anti-LGBT violence, a gunman killed 5 people at a nightclub in Colorado Springs during the night of November 19–20, 2022.Four warships of the U.S. Navy have been named the USS ''Colorado''.", "The first USS ''Colorado'' was named for the Colorado River and served in the Civil War and later the Asiatic Squadron, where it was attacked during the 1871 Korean Expedition.", "The later three ships were named in honor of the state, including an armored cruiser and the battleship USS ''Colorado'', the latter of which was the lead ship of her class and served in World War II in the Pacific beginning in 1941.At the time of the attack on Pearl Harbor, the battleship USS ''Colorado'' was located at the naval base in San Diego, California, and thus went unscathed.", "The most recent vessel to bear the name USS ''Colorado'' is Virginia-class submarine USS ''Colorado'' (SSN-788), which was commissioned in 2018." ], [ "Geography", "thumbColorado is notable for its diverse geography, which includes alpine mountains, high plains, deserts with huge sand dunes, and deep canyons.", "In 1861, the United States Congress defined the boundaries of the new Territory of Colorado exclusively by lines of latitude and longitude, stretching from 37°N to 41°N latitude, and from 102°02′48″W to 109°02′48″W longitude (25°W to 32°W from the Washington Meridian).", "After years of government surveys, the borders of Colorado were officially defined by 697 boundary markers and 697 straight boundary lines.", "Colorado, Wyoming, and Utah are the only states that have their borders defined solely by straight boundary lines with no natural features.", "The southwest corner of Colorado is the Four Corners Monument at 36°59′56″N, 109°2′43″W.", "The Four Corners Monument, located at the place where Colorado, New Mexico, Arizona, and Utah meet, is the only place in the United States where four states meet.===Plains===The arid high plains in Southeastern ColoradoApproximately half of Colorado is flat and rolling land.", "East of the Rocky Mountains are the Colorado Eastern Plains of the High Plains, the section of the Great Plains within Colorado at elevations ranging from roughly .", "The Colorado plains are mostly prairies but also include deciduous forests, buttes, and canyons.", "Precipitation averages annually.Eastern Colorado is presently mainly farmland and rangeland, along with small farming villages and towns.", "Corn, wheat, hay, soybeans, and oats are all typical crops.", "Most villages and towns in this region boast both a water tower and a grain elevator.", "Irrigation water is available from both surface and subterranean sources.", "Surface water sources include the South Platte, the Arkansas River, and a few other streams.", "Subterranean water is generally accessed through artesian wells.", "Heavy usage of these wells for irrigation purposes caused underground water reserves to decline in the region.", "Eastern Colorado also hosts a considerable amount and range of livestock, such as cattle ranches and hog farms.===Front Range===Front Range Peaks west of DenverRoughly 70% of Colorado's population resides along the eastern edge of the Rocky Mountains in the Front Range Urban Corridor between Cheyenne, Wyoming, and Pueblo, Colorado.", "This region is partially protected from prevailing storms that blow in from the Pacific Ocean region by the high Rockies in the middle of Colorado.", "The \"Front Range\" includes Denver, Boulder, Fort Collins, Loveland, Castle Rock, Colorado Springs, Pueblo, Greeley, and other townships and municipalities in between.", "On the other side of the Rockies, the significant population centers in western Colorado (which is known as \"The Western Slope\") are the cities of Grand Junction, Durango, and Montrose.===Mountains===Mount Elbert at is the highest summit of the Rocky Mountains and Colorado.To the west of the Great Plains of Colorado rises the eastern slope of the Rocky Mountains.", "Notable peaks of the Rocky Mountains include Longs Peak, Mount Blue Sky, Pikes Peak, and the Spanish Peaks near Walsenburg, in southern Colorado.", "This area drains to the east and the southeast, ultimately either via the Mississippi River or the Rio Grande into the Gulf of Mexico.The Rocky Mountains within Colorado contain 53 true peaks with a total of 58 that are or higher in elevation above sea level, known as fourteeners.", "These mountains are largely covered with trees such as conifers and aspens up to the tree line, at an elevation of about in southern Colorado to about in northern Colorado.", "Above this tree line, only alpine vegetation grows.", "Only small parts of the Colorado Rockies are snow-covered year-round.Much of the alpine snow melts by mid-August except for a few snow-capped peaks and a few small glaciers.", "The Colorado Mineral Belt, stretching from the San Juan Mountains in the southwest to Boulder and Central City on the front range, contains most of the historic gold- and silver-mining districts of Colorado.", "Mount Elbert is the highest summit of the Rocky Mountains.", "The 30 highest major summits of the Rocky Mountains of North America are all within the state.The summit of Mount Elbert at elevation in Lake County is the highest point in Colorado and the Rocky Mountains of North America.", "Colorado is the only U.S. state that lies entirely above 1,000 meters elevation.", "The point where the Arikaree River flows out of Yuma County, Colorado, and into Cheyenne County, Kansas, is the lowest in Colorado at elevation.", "This point, which is the highest low elevation point of any state, is higher than the high elevation points of 18 states and the District of Columbia.====Continental Divide====Grays Peak at is the highest point on the Continental Divide in North AmericaThe Continental Divide of the Americas extends along the crest of the Rocky Mountains.", "The area of Colorado to the west of the Continental Divide is called the Western Slope of Colorado.", "West of the Continental Divide, water flows to the southwest via the Colorado River and the Green River into the Gulf of California.Within the interior of the Rocky Mountains are several large parks which are high broad basins.", "In the north, on the east side of the Continental Divide is the North Park of Colorado.", "The North Park is drained by the North Platte River, which flows north into Wyoming and Nebraska.", "Just to the south of North Park, but on the western side of the Continental Divide, is the Middle Park of Colorado, which is drained by the Colorado River.", "The South Park of Colorado is the region of the headwaters of the South Platte River.===South Central region===The high desert lands that make up the San Luis Valley in Southern ColoradoIn south-central Colorado is the large San Luis Valley, where the headwaters of the Rio Grande are located.", "The northern part of the valley is the San Luis Closed Basin, an endorheic basin that helped created the Great Sand Dunes.", "The valley sits between the Sangre De Cristo Mountains and San Juan Mountains.", "The Rio Grande drains due south into New Mexico, Texas, and Mexico.", "Across the Sangre de Cristo Range to the east of the San Luis Valley lies the Wet Mountain Valley.", "These basins, particularly the San Luis Valley, lie along the Rio Grande Rift, a major geological formation of the Rocky Mountains, and its branches.===Western Slope===Maroon Bells, at , is part of White River National Forest and a tourist destinationThe Colorado National Monument near Grand Junction is made up of high desert canyons and sandstone rock formationsThe Western Slope of Colorado includes the western face of the Rocky Mountains and all of the area to the western border.", "This area includes several terrains and climates from alpine mountains to arid deserts.", "The Western Slope includes many ski resort towns in the Rocky Mountains and towns west to Utah.", "It is less populous than the Front Range but includes a large number of national parks and monuments.The northwestern corner of Colorado is a sparsely populated region, and it contains part of the noted Dinosaur National Monument, which not only is a paleontological area, but is also a scenic area of rocky hills, canyons, arid desert, and streambeds.", "Here, the Green River briefly crosses over into Colorado.The Western Slope of Colorado is drained by the Colorado River and its tributaries (primarily the Gunnison River, Green River, and the San Juan River).", "The Colorado River flows through Glenwood Canyon, and then through an arid valley made up of desert from Rifle to Parachute, through the desert canyon of De Beque Canyon, and into the arid desert of Grand Valley, where the city of Grand Junction is located.Also prominent is the Grand Mesa, which lies to the southeast of Grand Junction; the high San Juan Mountains, a rugged mountain range; and to the north and west of the San Juan Mountains, the Colorado Plateau.Grand Junction, Colorado, at the confluence of the Colorado and Gunnison Rivers, is the largest city on the Western Slope.", "Grand Junction and Durango are the only major centers of television broadcasting west of the Continental Divide in Colorado, though most mountain resort communities publish daily newspapers.", "Grand Junction is located at the juncture of Interstate 70 and US 50, the only major highways in western Colorado.", "Grand Junction is also along the major railroad of the Western Slope, the Union Pacific.", "This railroad also provides the tracks for Amtrak's California Zephyr passenger train, which crosses the Rocky Mountains between Denver and Grand Junction.The Western Slope includes multiple notable destinations in the Colorado Rocky Mountains, including Glenwood Springs, with its resort hot springs, and the ski resorts of Aspen, Breckenridge, Vail, Crested Butte, Steamboat Springs, and Telluride.Higher education in and near the Western Slope can be found at Colorado Mesa University in Grand Junction, Western Colorado University in Gunnison, Fort Lewis College in Durango, and Colorado Mountain College in Glenwood Springs and Steamboat Springs.The Four Corners Monument in the southwest corner of Colorado marks the common boundary of Colorado, New Mexico, Arizona, and Utah; the only such place in the United States." ], [ "Climate", "Köppen climate types of Colorado, using 1991-2020 climate normals.The climate of Colorado is more complex than states outside of the Mountain States region.", "Unlike most other states, southern Colorado is not always warmer than northern Colorado.", "Most of Colorado is made up of mountains, foothills, high plains, and desert lands.", "Mountains and surrounding valleys greatly affect the local climate.", "Northeast, east, and southeast Colorado are mostly the high plains, while Northern Colorado is a mix of high plains, foothills, and mountains.", "Northwest and west Colorado are predominantly mountainous, with some desert lands mixed in.", "Southwest and southern Colorado are a complex mixture of desert and mountain areas.===Eastern Plains===The climate of the Eastern Plains is semi-arid (Köppen climate classification: ''BSk'') with low humidity and moderate precipitation, usually from annually, although many areas near the rivers are semi-humid climate.", "The area is known for its abundant sunshine and cool, clear nights, which give this area a great average diurnal temperature range.", "The difference between the highs of the days and the lows of the nights can be considerable as warmth dissipates to space during clear nights, the heat radiation not being trapped by clouds.", "The Front Range urban corridor, where most of the population of Colorado resides, lies in a pronounced precipitation shadow as a result of being on the lee side of the Rocky Mountains.In summer, this area can have many days above 95 °F (35 °C) and often 100 °F (38 °C).", "On the plains, the winter lows usually range from 25 to −10 °F (−4 to −23 °C).", "About 75% of the precipitation falls within the growing season, from April to September, but this area is very prone to droughts.", "Most of the precipitation comes from thunderstorms, which can be severe, and from major snowstorms that occur in the winter and early spring.", "Otherwise, winters tend to be mostly dry and cold.In much of the region, March is the snowiest month.", "April and May are normally the rainiest months, while April is the wettest month overall.", "The Front Range cities closer to the mountains tend to be warmer in the winter due to Chinook winds which warms the area, sometimes bringing temperatures of 70 °F (21 °C) or higher in the winter.", "The average July temperature is 55 °F (13 °C) in the morning and 90 °F (32 °C) in the afternoon.", "The average January temperature is 18 °F (−8 °C) in the morning and 48 °F (9 °C) in the afternoon, although variation between consecutive days can be 40 °F (22 °C).===Front Range foothills===Just west of the plains and into the foothills, there is a wide variety of climate types.", "Locations merely a few miles apart can experience entirely different weather depending on the topography.", "Most valleys have a semi-arid climate, not unlike the eastern plains, which transitions to an alpine climate at the highest elevations.", "Microclimates also exist in local areas that run nearly the entire spectrum of climates, including subtropical highland (''Cfb/Cwb''), humid subtropical (''Cfa''), humid continental (''Dfa/Dfb''), Mediterranean (''Csa/Csb'') and subarctic (''Dfc'').===Extreme weather===Extreme weather changes are common in Colorado, although a significant portion of the extreme weather occurs in the least populated areas of the state.", "Thunderstorms are common east of the Continental Divide in the spring and summer, yet are usually brief.", "Hail is a common sight in the mountains east of the Divide and across the eastern Plains, especially the northeast part of the state.", "Hail is the most commonly reported warm-season severe weather hazard, and occasionally causes human injuries, as well as significant property damage.", "The eastern Plains are subject to some of the biggest hail storms in North America.", "Notable examples are the severe hailstorms that hit Denver on July 11, 1990, and May 8, 2017, the latter being the costliest ever in the state.The Eastern Plains are part of the extreme western portion of Tornado Alley; some damaging tornadoes in the Eastern Plains include the 1990 Limon F3 tornado and the 2008 Windsor EF3 tornado, which devastated a small town.", "Portions of the eastern Plains see especially frequent tornadoes, both those spawned from mesocyclones in supercell thunderstorms and from less intense landspouts, such as within the Denver convergence vorticity zone (DCVZ).The Plains are also susceptible to occasional floods and particularly severe flash floods, which are caused both by thunderstorms and by the rapid melting of snow in the mountains during warm weather.", "Notable examples include the 1965 Denver Flood, the Big Thompson River flooding of 1976 and the 2013 Colorado floods.", "Hot weather is common during summers in Denver.", "The city's record in 1901 for the number of consecutive days above 90 °F (32 °C) was broken during the summer of 2008.The new record of 24 consecutive days surpassed the previous record by almost a week.Much of Colorado is very dry, with the state averaging only of precipitation per year statewide.", "The state rarely experiences a time when some portion is not in some degree of drought.", "The lack of precipitation contributes to the severity of wildfires in the state, such as the Hayman Fire of 2002.Other notable fires include the Fourmile Canyon Fire of 2010, the Waldo Canyon Fire and High Park Fire of June 2012, and the Black Forest Fire of June 2013.Even these fires were exceeded in severity by the Pine Gulch Fire, Cameron Peak Fire, and East Troublesome Fire in 2020, all being the three largest fires in Colorado history (see 2020 Colorado wildfires).", "And the Marshall Fire which started on December 30, 2021, while not the largest in state history, was the most destructive ever in terms of property loss (see Marshall Fire).However, some of the mountainous regions of Colorado receive a huge amount of moisture from winter snowfalls.", "The spring melts of these snows often cause great waterflows in the Yampa River, the Colorado River, the Rio Grande, the Arkansas River, the North Platte River, and the South Platte River.Water flowing out of the Colorado Rocky Mountains is a very significant source of water for the farms, towns, and cities of the southwest states of New Mexico, Arizona, Utah, and Nevada, as well as the Midwest, such as Nebraska and Kansas, and the southern states of Oklahoma and Texas.", "A significant amount of water is also diverted for use in California; occasionally (formerly naturally and consistently), the flow of water reaches northern Mexico.===Climate change======Records===The highest official ambient air temperature ever recorded in Colorado was on July 20, 2019, at John Martin Dam.", "The lowest official air temperature was on February 1, 1985, at Maybell.+ Monthly normal high and low temperatures for various Colorado cities+(°F) (°C) City Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Alamosa 34/−22/−19 40/64/−14 50/1710/−8 59/2415/−4 69/3321/1 79/4126/5 82/4728/8 80/4627/8 73/4023/4 62/2517/−4 47/128/−11 35/12/−17 Colorado Springs 43/186/−8 45/207/−7 52/2611/−3 60/3316/1 69/4321/6 79/5126/11 85/5729/14 82/5628/13 75/4724/8 63/3617/2 51/2511/−4 42/186/−8 Denver 49/209/−7 49/219/−6 56/2913/−2 64/3518/2 73/4623/8 84/5429/12 92/6133/16 89/6032/16 81/5027/10 68/3720/3 55/2613/−3 47/188/−8 Grand Junction 38/173/−8 45/247/−4 57/3114/-1 65/3818/3 76/4724/8 88/5631/13 93/6334/17 90/6132/16 80/5227/11 66/4019/4 51/2811/−2 39/194/−7 Pueblo 47/148/−10 51/1711/−8 59/2615/−3 67/3419/1 77/4425/7 87/5331/12 93/5934/15 90/5832/14 82/4828/9 69/3421/1 56/2313/−5 46/148/−10===Extreme temperatures======Earthquakes===Despite its mountainous terrain, Colorado is relatively quiet seismically.", "The U.S. National Earthquake Information Center is located in Golden.On August 22, 2011, a 5.3 magnitude earthquake occurred west-southwest of the city of Trinidad.", "There were no casualties and only a small amount of damage was reported.", "It was the second-largest earthquake in Colorado's history.", "A magnitude 5.7 earthquake was recorded in 1973.In the early morning hours of August 24, 2018, four minor earthquakes rattled Colorado, ranging from magnitude 2.9 to 4.3.Colorado has recorded 525 earthquakes since 1973, a majority of which range 2 to 3.5 on the Richter scale." ], [ "Fauna", "Breckenridge naturalist Edwin Carter with a mounted gray wolf killed in the Colorado Rockies, ca.", "1890–1900.|alt=Photo of Breckenridge naturalist Edwin Carter standing next to a taxidermied gray wolf killed in the Colorado Rockies, circa.", "1890–1900.A process of extirpation by trapping and poisoning of the gray wolf (''Canis lupus'') from Colorado in the 1930s saw the last wild wolf in the state shot in 1945.A wolf pack recolonized Moffat County, Colorado in northwestern Colorado in 2019.Cattle farmers have expressed concern that a returning wolf population potentially threatens their herds.", "Coloradans voted to reintroduce gray wolves in 2020, with the state committing to a plan to have a population in the state by 2022 and permitting non-lethal methods of driving off wolves attacking livestock and pets.While there is fossil evidence of Harrington's mountain goat in Colorado between at least 800,000 years ago and its extinction with megafauna roughly 11,000 years ago, the mountain goat is not native to Colorado but was instead introduced to the state over time during the interval between 1947 and 1972.Despite being an artificially-introduced species, the state declared mountain goats a native species in 1993.In 2013, 2014, and 2019, an unknown illness killed nearly all mountain goat kids, leading to a Colorado Parks and Wildlife investigation.The native population of pronghorn in Colorado has varied wildly over the last century, reaching a low of only 15,000 individuals during the 1960s.", "However, conservation efforts succeeded in bringing the stable population back up to roughly 66,000 by 2013.The population was estimated to have reached 85,000 by 2019 and had increasingly more run-ins with the increased suburban housing along the eastern Front Range.", "State wildlife officials suggested that landowners would need to modify fencing to allow the greater number of pronghorns to move unabated through the newly developed land.", "Pronghorns are most readily found in the northern and eastern portions of the state, with some populations also in the western San Juan Mountains.Common wildlife found in the mountains of Colorado include mule deer, southwestern red squirrel, golden-mantled ground squirrel, yellow-bellied marmot, moose, American pika, and red fox, all at exceptionally high numbers, though moose are not native to the state.", "The foothills include deer, fox squirrel, desert cottontail, mountain cottontail, and coyote.", "The prairies are home to black-tailed prairie dog, the endangered swift fox, American badger, and white-tailed jackrabbit." ], [ "Counties", "The State of Colorado is divided into 64 counties.", "Two of these counties, the City and County of Broomfield and the City and County of Denver, have consolidated city and county governments.", "Counties are important units of government in Colorado since there are no civil townships or other minor civil divisions.The most populous county in Colorado is El Paso County, the home of the City of Colorado Springs.", "The second most populous county is the City and County of Denver, the state capital.", "Five of the 64 counties now have more than 500,000 residents, while 12 have fewer than 5,000 residents.", "The ten most populous Colorado counties are all located in the Front Range Urban Corridor.", "Mesa County is the most populous county on the Colorado Western Slope.+The 16 most populous Colorado counties2022 RankCountyCounty seatLargest community2022 Population1El Paso CountyColorado SpringsColorado Springs740,5672City and County of DenverDenverDenver713,2523Arapahoe CountyLittletonAurora655,8084Jefferson CountyGoldenLakewood576,1435Adams CountyBrightonThornton527,5756Douglas CountyCastle RockHighlands Ranch375,9887Larimer CountyFort CollinsFort Collins366,7788Weld CountyGreeleyGreeley350,1769Boulder CountyBoulderBoulder327,46810Pueblo CountyPuebloPueblo169,54411Mesa CountyGrand JunctionGrand Junction158,63612City and County of BroomfieldBroomfieldBroomfield76,12113Garfield CountyGlenwood SpringsRifle62,27114La Plata CountyDurangoDurango56,60715Eagle CountyEagleEdwards55,28516Fremont CountyCañon CityCañon City49,621===Municipalities===Colorado has 272 active incorporated municipalities, comprising 197 towns, 73 cities, and two consolidated city and county governments.", "At the 2020 United States census, 4,299,942 of the 5,773,714 Colorado residents (74.47%) lived in one of these 272 municipalities.", "Another 714,417 residents (12.37%) lived in one of the 210 census-designated places, while the remaining 759,355 residents (13.15%) lived in the many rural and mountainous areas of the state.Colorado municipalities operate under one of five types of municipal governing authority.", "Colorado currently has two consolidated city and county governments, 61 home rule cities, 12 statutory cities, 35 home rule towns, 161 statutory towns, and one territorial charter municipality.The most populous municipality is the City and County of Denver.", "Colorado has 12 municipalities with more than 100,000 residents, and 17 with fewer than 100 residents.", "The 16 most populous Colorado municipalities are all located in the Front Range Urban Corridor.", "The City of Grand Junction is the most populous municipality on the Colorado Western Slope.", "The Town of Carbonate has had no year-round population since the 1890 census due to its severe winter weather and difficult access.+The 25 most populous Colorado municipalities2022 RankMunicipalityCounty2022 Population1City and County of DenverCity and County of Denver713,2522City of Colorado SpringsEl Paso County486,2483City of AuroraArapahoe, Adams, and Douglas counties393,5374City of Fort CollinsLarimer County169,2495City of LakewoodJefferson County156,1206City of ThorntonAdams and Weld counties143,2827City of ArvadaJefferson and Adams counties121,5818City of WestminsterAdams and Jefferson counties114,5339City of PuebloPueblo County111,45610City of GreeleyWeld County109,20911City of CentennialArapahoe County105,86512City of BoulderBoulder County105,48513City of LongmontBoulder and Weld counties98,68714Town of Castle RockDouglas County80,19115City of LovelandLarimer County77,88416City and County of BroomfieldCity and County of Broomfield76,12117City of Grand JunctionMesa County68,03418City of Commerce CityAdams County66,11519Town of ParkerDouglas County61,22220City of LittletonArapahoe, Jefferson, and Douglas counties44,75521City of BrightonAdams and Weld counties41,88122Town of WindsorWeld and Larimer counties38,51023City of NorthglennAdams and Weld counties38,10624City of EnglewoodArapahoe County33,64225Town of ErieWeld and Boulder counties33,104===Unincorporated communities===In addition to its 272 municipalities, Colorado has 210 unincorporated census-designated places (CDPs) and many other small communities.", "The most populous unincorporated community in Colorado is Highlands Ranch south of Denver.", "The seven most populous CDPs are located in the Front Range Urban Corridor.", "The Clifton CDP is the most populous CDP on the Colorado Western Slope.+The ten most populous census-designated places in Colorado2020 RankCensus-designated placeCounty2020 census1Highlands Ranch CDPDouglas County103,4442Security-Widefield CDPEl Paso County38,6393Dakota Ridge CDPJefferson County33,8924Ken Caryl CDPJefferson County33,8115Pueblo West CDPPueblo County33,0866Columbine CDPJefferson and Arapahoe counties25,2297Four Square Mile CDPArapahoe County22,8728Clifton CDPMesa County20,4139Cimarron Hills CDPEl Paso County19,31110Sherrelwood CDPAdams County19,228===Special districts===Colorado has more than 4,000 special districts, most with property tax authority.", "These districts may provide schools, law enforcement, fire protection, water, sewage, drainage, irrigation, transportation, recreation, infrastructure, cultural facilities, business support, redevelopment, or other services.Some of these districts have the authority to levy sales tax as well as property tax and use fees.", "This has led to a hodgepodge of sales tax and property tax rates in Colorado.", "There are some street intersections in Colorado with a different sales tax rate on each corner, sometimes substantially different.Some of the more notable Colorado districts are:* The Regional Transportation District (RTD), which affects the counties of Denver, Boulder, Jefferson, and portions of Adams, Arapahoe, Broomfield, and Douglas Counties* The Scientific and Cultural Facilities District (SCFD), a special regional tax district with physical boundaries contiguous with county boundaries of Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas, and Jefferson Counties** It is a 0.1% retail sales and uses tax (one penny on every $10).", "** According to the Colorado statute, the SCFD distributes the money to local organizations on an annual basis.", "These organizations must provide for the enlightenment and entertainment of the public through the production, presentation, exhibition, advancement, or preservation of art, music, theater, dance, zoology, botany, natural history, or cultural history.", "** As directed by statute, SCFD recipient organizations are currently divided into three \"tiers\" among which receipts are allocated by percentage.", "*** Tier I includes regional organizations: the Denver Art Museum, the Denver Botanic Gardens, the Denver Museum of Nature and Science, the Denver Zoo, and the Denver Center for the Performing Arts.", "It receives 65.5%.", "*** Tier II currently includes 26 regional organizations.", "Tier II receives 21%.", "*** Tier III has more than 280 local organizations such as small theaters, orchestras, art centers, natural history, cultural history, and community groups.", "Tier III organizations apply for funding from the county cultural councils via a grant process.", "This tier receives 13.5%.", "** An 11-member board of directors oversees the distributions by the Colorado Revised Statutes.", "Seven board members are appointed by county commissioners (in Denver, the Denver City Council) and four members are appointed by the Governor of Colorado.", "* The Football Stadium District (FD or FTBL), approved by the voters to pay for and help build the Denver Broncos' stadium Empower Field at Mile High.", "* Local Improvement Districts (LID) within designated areas of Jefferson and Broomfield counties.", "* The Metropolitan Major League Baseball Stadium District, approved by voters to pay for and help build the Colorado Rockies' stadium Coors Field.", "* Regional Transportation Authority (RTA) taxes at varying rates in Basalt, Carbondale, Glenwood Springs, and Gunnison County." ], [ "Statistical areas", "An enlargeable map of the 17 core-based statistical areas of ColoradoMost recently on March 6, 2020, the Office of Management and Budget defined 21 statistical areas for Colorado comprising four combined statistical areas, seven metropolitan statistical areas, and ten micropolitan statistical areas.The most populous of the seven metropolitan statistical areas in Colorado is the 10-county Denver-Aurora-Lakewood, CO Metropolitan Statistical Area with a population of 2,963,821 at the 2020 United States census, an increase of +15.29% since the 2010 census.The more extensive 12-county Denver-Aurora, CO Combined Statistical Area had a population of 3,623,560 at the 2020 census, an increase of +17.23% since the 2010 census.The most populous extended metropolitan region in Rocky Mountain Region is the 18-county Front Range Urban Corridor along the northeast face of the Southern Rocky Mountains.", "This region with Denver at its center had a population of 5,055,344 at the 2020 census, an increase of +16.65% since the 2010 census." ], [ "Demographics", "Colorado population density mapThe United States Census Bureau estimated the population of Colorado on July 1, 2023, at 5,877,610, a 1.80% increase since the 2020 United States census.Ethnic composition as of the 2020 census Race and EthnicityNon-HispanicTotal White (non-Hispanic) Hispanic or Latino Black (non-Hispanic) Asian Native American Pacific Islander Other + Colorado historical racial demographics Racial composition 1970 1990 2000 2010 White (includes White Hispanics) % % % % Black % % % % Asian % % % % Native % % % % Native Hawaiian andother Pacific Islander – – % % Other race % % % % Two or more races – – % %Ethnic origins in ColoradoMap of counties in Colorado by racial plurality, per the 2020 U.S. censusColoradan Hispanics and Latinos (of any race and heritage) made up 20.7% of the population.", "According to the 2000 census, the largest ancestry groups in Colorado are German (22%) including those of Swiss and Austrian descent, Mexican (18%), Irish (12%), and English (12%).", "Persons reporting German ancestry are especially numerous in the Front Range, the Rockies (west-central counties), and Eastern parts/High Plains.Colorado has a high proportion of Hispanic, mostly Mexican-American, citizens in Metropolitan Denver, Colorado Springs, as well as the smaller cities of Greeley and Pueblo, and elsewhere.", "Southern, Southwestern, and Southeastern Colorado have a large number of Hispanos, the descendants of the early settlers of colonial Spanish origin.", "In 1940, the U.S. Census Bureau reported Colorado's population as 8.2% Hispanic and 90.3% non-Hispanic White.", "The Hispanic population of Colorado has continued to grow quickly over the past decades.", "By 2019, Hispanics made up 22% of Colorado's population, and Non-Hispanic Whites made up 70%.", "Spoken English in Colorado has many Spanish idioms.Colorado also has some large African-American communities located in Denver, in the neighborhoods of Montbello, Five Points, Whittier, and many other East Denver areas.", "The state has sizable numbers of Asian-Americans of Mongolian, Chinese, Filipino, Korean, Southeast Asian, and Japanese descent.", "The highest population of Asian Americans can be found on the south and southeast side of Denver, as well as some on Denver's southwest side.", "The Denver metropolitan area is considered more liberal and diverse than much of the state when it comes to political issues and environmental concerns.The population of Native Americans in the state is small.", "Native Americans are concentrated in metropolitan Denver and the southwestern corner of Colorado, where there are two Ute reservations.The majority of Colorado's immigrants are from Mexico, India, China, Vietnam, Korea, Germany and Canada.There were a total of 70,331 births in Colorado in 2006.", "(Birth rate of 14.6 per thousand.)", "In 2007, non-Hispanic Whites were involved in 59.1% of all births.", "Some 14.06% of those births involved a non-Hispanic White person and someone of a different race, most often with a couple including one Hispanic.", "A birth where at least one Hispanic person was involved counted for 43% of the births in Colorado.", "As of the 2010 census, Colorado has the seventh highest percentage of Hispanics (20.7%) in the U.S. behind New Mexico (46.3%), California (37.6%), Texas (37.6%), Arizona (29.6%), Nevada (26.5%), and Florida (22.5%).", "Per the 2000 census, the Hispanic population is estimated to be 918,899, or approximately 20% of the state's total population.", "Colorado has the 5th-largest population of Mexican-Americans, behind California, Texas, Arizona, and Illinois.", "In percentages, Colorado has the 6th-highest percentage of Mexican-Americans, behind New Mexico, California, Texas, Arizona, and Nevada.===Birth data===In 2011, 46% of Colorado's population younger than the age of one were minorities, meaning that they had at least one parent who was not non-Hispanic White.", "''Note: Births in table do not add up, because Hispanics are counted both by their ethnicity and by their race, giving a higher overall number.", "''+ Live births by single race/ethnicity of mother Race 2013 2014 2015 2016 2017 2018 2019 2020 2021 White: 57,491 (88.4%) 58,117 (88.3%) 58,756 (88.2%) ... ... ... ... ... ... > Non-Hispanic whites 39,872 (61.3%) 40,629 (61.7%) 40,878 (61.4%) 39,617 (59.5%) 37,516 (58.3%) 36,466 (58.0%) 36,022 (57.3%) 34,924 (56.8%) 36,334 (57.7%) Black 3,760 (5.8%) 3,926 (6.0%) 4,049 (6.1%) 3,004 (4.5%) 3,110 (4.8%) 3,032 (4.8%) 3,044 (4.8%) 3,146 (5.1%) 2,988 (4.7%) Asian 2,863 (4.4%) 3,010 (4.6%) 2,973 (4.5%) 2,617 (3.9%) 2,611 (4.1%) 2,496 (4.0%) 2,540 (4.0%) 2,519 (4.1%) 2,490 (4.0%) American Indian 793 (1.2%) 777 (1.2%) 803 (1.2%) 412 (0.6%) 421 (0.7%) 352 (0.6%) 365 (0.6%) 338 (0.5%) 323 (0.5%) Pacific Islander ... ... ... 145 (0.2%) 145 (0.2%) 155 (0.2%) 168 (0.3%) 169 (0.3%) 202 (0.3%) ''Hispanic'' (of any race) ''17,821'' (27.4%) ''17,665'' (26.8%) ''18,139'' (27.2%) ''18,513'' (27.8%) ''18,125'' (28.2%) ''17,817'' (28.3%) ''18,205'' (29.0%) ''18,111'' (29.4%) ''18,362'' (29.2%) '''Total Colorado''' '''65,007''' (100%) '''65,830''' (100%) '''66,581''' (100%) '''66,613''' (100%) '''64,382''' (100%) '''62,885''' (100%) '''62,869''' (100%) '''61,494''' (100%) '''62,949''' (100%)* Since 2016, data for births of White Hispanic origin are not collected, but included in one ''Hispanic'' group; persons of Hispanic origin may be of any race.In 2017, Colorado recorded the second-lowest fertility rate in the United States outside of New England, after Oregon, at 1.63 children per woman.", "Significant, contributing factors to the decline in pregnancies were the Title X Family Planning Program and an intrauterine device grant from Warren Buffett's family.===Language===English, the official language of the state, is the most commonly spoken in Colorado.", "One Native American language still spoken in Colorado is the Colorado River Numic language also known as the Ute dialect.The most common non-English language spoken in the state is Spanish.===Religion===Major religious affiliations of the people of Colorado as of 2014 were 64% Christian, of whom there are 44% Protestant, 16% Roman Catholic, 3% Mormon, and 1% Eastern Orthodox.", "Other religious breakdowns according to the Pew Research Center were 1% Jewish, 1% Muslim, 1% Buddhist and 4% other.", "The religiously unaffiliated made up 29% of the population.", "In 2020, according to the Public Religion Research Institute, Christianity was 66% of the population.", "Judaism was also reported to have increased in this separate study, forming 2% of the religious landscape, while the religiously unaffiliated were reported to form 28% of the population in this separate study.", "In 2022, the same organization reported 61% was Christian (39% Protestant, 19% Catholic, 2% Mormon, 1% Eastern Orthodox), 2% New Age, 1% Jewish, 1% Hindu, and 34% religiously unaffiliated.According to the Association of Religion Data Archives, the largest Christian denominations by the number of adherents in 2010 were the Catholic Church with 811,630; multi-denominational Evangelical Protestants with 229,981; and the Church of Jesus Christ of Latter-day Saints with 151,433.In 2020, the Association of Religion Data Archives determined the largest Christian denominations were Catholics (873,236), non/multi/inter-denominational Protestants (406,798), and Mormons (150,509).", "Throughout its non-Christian population, there were 12,500 Hindus, 7,101 Hindu Yogis, and 17,369 Buddhists at the 2020 study.Our Lady of Guadalupe Catholic Church was the first permanent Catholic parish in modern-day Colorado and was constructed by Spanish colonists from New Mexico in modern-day Conejos.", "Latin Church Catholics are served by three dioceses: the Archdiocese of Denver and the Dioceses of Colorado Springs and Pueblo.The first permanent settlement by members of the Church of Jesus Christ of Latter-day Saints in Colorado arrived from Mississippi and initially camped along the Arkansas River just east of the present-day site of Pueblo." ], [ "Health", "Colorado is generally considered among the healthiest states by behavioral and healthcare researchers.", "Among the positive contributing factors is the state's well-known outdoor recreation opportunities and initiatives.", "However, there is a stratification of health metrics with wealthier counties such as Douglas and Pitkin performing significantly better relative to southern, less wealthy counties such as Huerfano and Las Animas.=== Obesity ===According to several studies, Coloradans have the lowest rates of obesity of any state in the US.", ", 24% of the population was considered medically obese, and while the lowest in the nation, the percentage had increased from 17% in 2004.=== Life expectancy ===According to a report in the Journal of the American Medical Association, residents of Colorado had a 2014 life expectancy of 80.21 years, the longest of any U.S. state.=== Homelessness ===According to HUD's 2022 Annual Homeless Assessment Report, there were an estimated 10,397 homeless people in Colorado." ], [ "Economy", "Denver Energy Center lies in the Denver financial district along 17th Street, known as the ''Wall Street of the West''Corn growing in Larimer CountyIn 2019 the total employment was 2,473,192.The number of employer establishments is 174,258.The total state product in 2015 was $318.6 billion.", "Median Annual Household Income in 2016 was $70,666, 8th in the nation.", "Per capita personal income in 2010 was $51,940, ranking Colorado 11th in the nation.", "The state's economy broadened from its mid-19th-century roots in mining when irrigated agriculture developed, and by the late 19th century, raising livestock had become important.", "Early industry was based on the extraction and processing of minerals and agricultural products.", "Current agricultural products are cattle, wheat, dairy products, corn, and hay.The federal government operates several federal facilities in the state, including NORAD (North American Aerospace Defense Command), United States Air Force Academy, Schriever Air Force Base located approximately 10 miles (16 kilometers) east of Peterson Air Force Base, and Fort Carson, both located in Colorado Springs within El Paso County; NOAA, the National Renewable Energy Laboratory (NREL) in Golden, and the National Institute of Standards and Technology in Boulder; U.S. Geological Survey and other government agencies at the Denver Federal Center near Lakewood; the Denver Mint, Buckley Space Force Base, the Tenth Circuit Court of Appeals, and the Byron G. Rogers Federal Building and United States Courthouse in Denver; and a federal Supermax Prison and other federal prisons near Cañon City.", "In addition to these and other federal agencies, Colorado has abundant National Forest land and four National Parks that contribute to federal ownership of of land in Colorado, or 37% of the total area of the state.In the second half of the 20th century, the industrial and service sectors expanded greatly.", "The state's economy is diversified and is notable for its concentration on scientific research and high-technology industries.", "Other industries include food processing, transportation equipment, machinery, chemical products, the extraction of metals such as gold (see Gold mining in Colorado), silver, and molybdenum.", "Colorado now also has the largest annual production of beer in any state.", "Denver is an important financial center.The state's diverse geography and majestic mountains attract millions of tourists every year, including 85.2 million in 2018.Tourism contributes greatly to Colorado's economy, with tourists generating $22.3 billion in 2018.Several nationally known brand names have originated in Colorado factories and laboratories.", "From Denver came the forerunner of telecommunications giant Qwest in 1879, Samsonite luggage in 1910, Gates belts and hoses in 1911, and Russell Stover Candies in 1923.Kuner canned vegetables began in Brighton in 1864.From Golden came Coors beer in 1873, CoorsTek industrial ceramics in 1920, and Jolly Rancher candy in 1949.CF&I railroad rails, wire, nails, and pipe debuted in Pueblo in 1892.Holly Sugar was first milled from beets in Holly in 1905, and later moved its headquarters to Colorado Springs.", "The present-day Swift packed meat of Greeley evolved from Monfort of Colorado, Inc., established in 1930.Estes model rockets were launched in Penrose in 1958.Fort Collins has been the home of Woodward Governor Company's motor controllers (governors) since 1870, and Waterpik dental water jets and showerheads since 1962.Celestial Seasonings herbal teas have been made in Boulder since 1969.Rocky Mountain Chocolate Factory made its first candy in Durango in 1981.Colorado has a flat 4.63% income tax, regardless of income level.", "On 3 November 2020 voters authorized an initiative to lower that income tax rate to 4.55 percent.", "Unlike most states, which calculate taxes based on federal ''adjusted gross income'', Colorado taxes are based on ''taxable income''—income after federal exemptions and federal itemized (or standard) deductions.", "Colorado's state sales tax is 2.9% on retail sales.", "When state revenues exceed state constitutional limits, according to Colorado's Taxpayer Bill of Rights legislation, full-year Colorado residents can claim a sales tax refund on their individual state income tax return.", "Many counties and cities charge their own rates, in addition to the base state rate.", "There are also certain county and special district taxes that may apply.Real estate and personal business property are taxable in Colorado.", "The state's senior property tax exemption was temporarily suspended by the Colorado Legislature in 2003.The tax break was scheduled to return for the assessment year 2006, payable in 2007., the state's unemployment rate was 4.2%.The West Virginia teachers' strike in 2018 inspired teachers in other states, including Colorado, to take similar action.=== Agriculture ===Corn is grown in the Eastern Plains of Colorado.", "Arid conditions and drought negatively impacted yields in 2020 and 2022.=== Natural resources ===An oil well in western ColoradoColorado has significant hydrocarbon resources.", "According to the Energy Information Administration, Colorado hosts seven of the largest natural gas fields in the United States, and two of the largest oil fields.", "Conventional and unconventional natural gas output from several Colorado basins typically accounts for more than five percent of annual U.S. natural gas production.", "Colorado's oil shale deposits hold an estimated of oil—nearly as much oil as the entire world's proven oil reserves.", "Substantial deposits of bituminous, subbituminous, and lignite coal are found in the state.Uranium mining in Colorado goes back to 1872, when pitchblende ore was taken from gold mines near Central City, Colorado.", "Not counting byproduct uranium from phosphate, Colorado is considered to have the third-largest uranium reserves of any U.S. state, behind Wyoming and New Mexico.", "When Colorado and Utah dominated radium mining from 1910 to 1922, uranium and vanadium were the byproducts (giving towns like present-day Superfund site Uravan their names).", "Uranium price increases from 2001 to 2007 prompted several companies to revive uranium mining in Colorado.", "During the 1940s certain communities–including Naturita and Paradox–earned the moniker of \"yellowcake towns\" from their relationship with uranium mining.", "Price drops and financing problems in late 2008 forced these companies to cancel or scale back the uranium-mining project.", "As of 2016, there were no major uranium mining operations in the state, though plans existed to restart production.===Electricity generation===Colorado's high Rocky Mountain ridges and eastern plains offer wind power potential, and geologic activity in the mountain areas provides the potential for geothermal power development.", "Much of the state is sunny and could produce solar power.", "Major rivers flowing from the Rocky Mountains offer hydroelectric power resources." ], [ "Culture", "History Colorado Center in DenverStreet art in Denver===Arts and film===* List of museums in Colorado* List of theaters in Colorado* Music of ColoradoSeveral film productions have been shot on location in Colorado, especially prominent Westerns like ''True Grit'', ''The Searchers'', ''City Slickers,'' ''Butch Cassidy and the Sundance Kid, and My Life With the Walter Boys''.", "Several historic military forts, railways with trains still operating, and mining ghost towns have been used and transformed for historical accuracy in well-known films.", "There are also several scenic highways and mountain passes that helped to feature the open road in films such as ''Vanishing Point'', ''Bingo'' and ''Starman''.", "Some Colorado landmarks have been featured in films, such as The Stanley Hotel in ''Dumb and Dumber'' and ''The Shining'' and the Sculptured House in ''Sleeper''.", "In 2015, ''Furious 7'' was to film driving sequences on Pikes Peak Highway in Colorado.", "The TV adult-animated series ''South Park'' takes place in central Colorado in the titular town.", "Additionally, The TV series ''Good Luck Charlie'' was set, but not filmed, in Denver, Colorado.", "The Colorado Office of Film and Television has noted that more than 400 films have been shot in Colorado.There are also several established film festivals in Colorado, including Aspen Shortsfest, Boulder International Film Festival, Castle Rock Film Festival, Denver Film Festival, Festivus Film Festival, Mile High Horror Film Festival, Moondance International Film Festival, Mountainfilm in Telluride, Rocky Mountain Women's Film Festival, and Telluride Film Festival.Many notable writers have lived or spent extended periods in Colorado.", "Beat Generation writers Jack Kerouac and Neal Cassady lived in and around Denver for several years each.", "Irish playwright Oscar Wilde visited Colorado on his tour of the United States in 1882, writing in his 1906 ''Impressions of America'' that Leadville was \"the richest city in the world.", "It has also got the reputation of being the roughest, and every man carries a revolver.", "\"===Cuisine===Colorado is known for its Southwest and Rocky Mountain cuisine, with Mexican restaurants found throughout the state.Boulder was named America's Foodiest Town 2010 by Bon Appétit.", "Boulder, and Colorado in general, is home to several national food and beverage companies, top-tier restaurants and farmers' markets.", "Boulder also has more Master Sommeliers per capita than any other city, including San Francisco and New York.", "Denver is known for steak, but now has a diverse culinary scene with many restaurants.Polidori Sausage is a brand of pork products available in supermarkets, which originated in Colorado, in the early 20th century.The Food & Wine Classic is held annually each June in Aspen.", "Aspen also has a reputation as the culinary capital of the Rocky Mountain region.===Wine and beer===Colorado wines include award-winning varietals that have attracted favorable notice from outside the state.", "With wines made from traditional ''Vitis vinifera'' grapes along with wines made from cherries, peaches, plums, and honey, Colorado wines have won top national and international awards for their quality.", "Colorado's grape growing regions contain the highest elevation vineyards in the United States, with most viticulture in the state practiced between above sea level.", "The mountain climate ensures warm summer days and cool nights.", "Colorado is home to two designated American Viticultural Areas of the Grand Valley AVA and the West Elks AVA, where most of the vineyards in the state are located.", "However, an increasing number of wineries are located along the Front Range.", "In 2018, Wine Enthusiast Magazine named Colorado's Grand Valley AVA in Mesa County, Colorado, as one of the Top Ten wine travel destinations in the world.Colorado is home to many nationally praised microbreweries, including New Belgium Brewing Company, Odell Brewing Company, Great Divide Brewing Company, and Bristol Brewing Company.", "The area of northern Colorado near and between the cities of Denver, Boulder, and Fort Collins is known as the \"Napa Valley of Beer\" due to its high density of craft breweries.===Marijuana and hemp===Colorado is open to cannabis (marijuana) tourism.", "With the adoption of the 64th state amendment in 2012, Colorado became the first state in the union to legalize marijuana for medicinal (2000), industrial (referring to hemp, 2012), and recreational (2012) use.", "Colorado's marijuana industry sold $1.31 billion worth of marijuana in 2016 and $1.26 billion in the first three-quarters of 2017.The state generated tax, fee, and license revenue of $194 million in 2016 on legal marijuana sales.", "Colorado regulates hemp as any part of the plant with less than 0.3% THC.On April 4, 2014, Senate Bill 14–184 addressing oversight of Colorado's industrial hemp program was first introduced, ultimately being signed into law by Governor John Hickenlooper on May 31, 2014.====Medicinal use====On November 7, 2000, 54% of Colorado voters passed Amendment 20, which amends the Colorado State constitution to allow the medical use of marijuana.", "A patient's medical use of marijuana, within the following limits, is lawful:* (I) No more than of a usable form of marijuana; and* (II) No more than twelve marijuana plants, with six or fewer being mature, flowering plants that are producing a usable form of marijuana.Currently, Colorado has listed \"eight medical conditions for which patients can use marijuana—cancer, glaucoma, HIV/AIDS, muscle spasms, seizures, severe pain, severe nausea and cachexia, or dramatic weight loss and muscle atrophy\".", "While governor, John Hickenlooper allocated about half of the state's $13 million \"Medical Marijuana Program Cash Fund\" to medical research in the 2014 budget.", "By 2018, the Medical Marijuana Program Cash Fund was the \"largest pool of pot money in the state\" and was used to fund programs including research into pediatric applications for controlling autism symptoms.====Recreational use====On November 6, 2012, voters amended the state constitution to protect \"personal use\" of marijuana for adults, establishing a framework to regulate marijuana in a manner similar to alcohol.", "The first recreational marijuana shops in Colorado, and by extension the United States, opened their doors on January 1, 2014.===Sports===The Colorado Rockies baseball club at Coors Field|172x172pxEmpower Field at Mile High in Denver, home field of the Denver Broncos and the Denver Outlaws|172x172pxBall Arena, home of the Denver Nuggets, the Colorado Avalanche, and the Colorado Mammoth|172x172pxDick's Sporting Goods Park, home of the Colorado Rapids|172x172pxColorado has five major professional sports leagues, all based in the Denver metropolitan area.", "Colorado is the least populous state with a franchise in each of the major professional sports leagues.The Colorado Springs Snow Sox professional baseball team is based in Colorado Springs.", "The team is a member of the Pecos League, an independent baseball league which is not affiliated with Major or Minor League Baseball.The Pikes Peak International Hill Climb is a major hill climbing motor race held on the Pikes Peak Highway.The Cherry Hills Country Club has hosted several professional golf tournaments, including the U.S. Open, U.S. Senior Open, U.S. Women's Open, PGA Championship and BMW Championship.====Professional sports teams====TeamHomeFirst gameSportLeagueColorado AvalancheDenverIce hockeyNational Hockey LeagueColorado EaglesLovelandIce hockeyAmerican Hockey LeagueColorado MammothDenverLacrosseNational Lacrosse LeagueColorado RapidsCommerce CitySoccerMajor League SoccerColorado Rapids 2DenverSoccerMLS Next ProColorado RockiesDenverBaseballMajor League BaseballColorado Springs Switchbacks FCColorado SpringsSoccerUSL ChampionshipDenver BarbariansDenverSpring 1967Rugby unionPacific Rugby PremiershipDenver BroncosDenverAmerican footballNational Football LeagueDenver NuggetsDenverBasketballNational Basketball AssociationGlendale RaptorsGlendaleFall 2006Rugby unionMajor League RugbyGrand Junction RockiesGrand JunctionBaseballPioneer LeagueNorthern Colorado Hailstorm FCWindsorSoccerUSL League OneNorthern Colorado OwlzWindsorBaseballPioneer LeagueRocky Mountain VibesColorado SpringsBaseballPioneer League====College athletics====Weidner Field in Colorado Springs, home of the Colorado Springs Switchbacks FC|172x172pxThe following universities and colleges participate in the National Collegiate Athletic Association Division I.", "The most popular college sports program is the University of Colorado Buffaloes, who used to play in the Big-12 but now play in the Pac-12.They have won the 1957 and 1991 Orange Bowl, 1995 Fiesta Bowl, and 1996 Cotton Bowl Classic.+NCAA Division I athletic programs in Colorado Team School City Conference Air Force Falcons United States Air Force Academy Colorado Springs Mountain West Colorado Buffaloes University of Colorado Boulder Boulder Pac-12 Colorado State Rams Colorado State University Fort Collins Mountain West Denver Pioneers University of Denver Denver NCHC / Summit Northern Colorado Bears University of Northern Colorado Greeley Big SkyColorado College TigersColorado CollegeColorado SpringsNCHC / Mountain West" ], [ "Transportation", "A Colorado state welcome signColorado's primary mode of transportation (in terms of passengers) is its highway system.", "Interstate 25 (I-25) is the primary north–south highway in the state, connecting Pueblo, Colorado Springs, Denver, and Fort Collins, and extending north to Wyoming and south to New Mexico.", "I-70 is the primary east–west corridor.", "It connects Grand Junction and the mountain communities with Denver and enters Utah and Kansas.", "The state is home to a network of US and Colorado highways that provide access to all principal areas of the state.", "Many smaller communities are connected to this network only via county roads.The main terminal of Denver International Airport evokes the peaks of the Front Range.Denver International Airport (DIA) is the third-busiest domestic U.S. and international airport in the world by passenger traffic.", "DIA handles by far the largest volume of commercial air traffic in Colorado and is the busiest U.S. hub airport between Chicago and the Pacific coast, making Denver the most important airport for connecting passenger traffic in the western United States.Public transportation bus services are offered both intra-city and inter-city—including the Denver metro area's RTD services.", "The Regional Transportation District (RTD) operates the popular RTD Bus & Rail transit system in the Denver Metropolitan Area.", "the RTD rail system had 170 light-rail vehicles, serving of track.", "In addition to local public transit, intercity bus service is provided by Burlington Trailways, Bustang, Express Arrow, and Greyhound Lines.The westbound and eastbound ''California Zephyrs'' meet in the Glenwood Canyon.Amtrak operates two passenger rail lines in Colorado, the California Zephyr and Southwest Chief.", "Colorado's contribution to world railroad history was forged principally by the Denver and Rio Grande Western Railroad which began in 1870 and wrote the book on mountain railroading.", "In 1988 the \"Rio Grande\" was acquired, but was merged into, the Southern Pacific Railroad by their joint owner Philip Anschutz.", "On September 11, 1996, Anschutz sold the combined company to the Union Pacific Railroad, creating the largest railroad network in the United States.", "The Anschutz sale was partly in response to the earlier merger of Burlington Northern and Santa Fe which formed the large Burlington Northern and Santa Fe Railway (BNSF), Union Pacific's principal competitor in western U.S. railroading.", "Both Union Pacific and BNSF have extensive freight operations in Colorado.Colorado's freight railroad network consists of 2,688 miles of Class I trackage.", "It is integral to the U.S. economy, being a critical artery for the movement of energy, agriculture, mining, and industrial commodities as well as general freight and manufactured products between the East and Midwest and the Pacific coast states.In August 2014, Colorado began to issue driver licenses to aliens not lawfully in the United States who lived in Colorado.", "In September 2014, KCNC reported that 524 non-citizens were issued Colorado driver licenses that are normally issued to U.S. citizens living in Colorado." ], [ "Education", "The first institution of higher education in the Colorado Territory was the Colorado Seminary, opened on November 16, 1864, by the Methodist Episcopal Church.", "The seminary closed in 1867 but reopened in 1880 as the University of Denver.", "In 1870, the Bishop George Maxwell Randall of the Episcopal Church's Missionary District of Colorado and Parts Adjacent opened the first of what become the Colorado University Schools which would include the Territorial School of Mines opened in 1873 and sold to the Colorado Territory in 1874.These schools were initially run by the Episcopal Church.", "An 1861 territorial act called for the creation of a public university in Boulder, though it would not be until 1876 that the University of Colorado was founded.", "The 1876 act also renamed Territorial School of Mines as the Colorado School of Mines.", "An 1870 territorial act created the Agricultural College of Colorado which opened in 1879.The college was renamed the Colorado State College of Agriculture and Mechanic Arts in 1935, and became Colorado State University in 1957.The first Catholic college in Colorado was the Jesuit Sacred Heart College, which was founded in New Mexico in 1877, moved to Morrison in 1884, and to Denver in 1887.The college was renamed Regis College in 1921 and Regis University in 1991.On April 1, 1924, armed students patrolled the campus after a burning cross was found, the climax of tensions between Regis College and the locally-powerful Ku Klux Klan.Following a 1950 assessment by the Service Academy Board, it was determined that there was a need to supplement the U.S. Military and Naval Academies with a third school that would provide commissioned officers for the newly independent Air Force.", "On April 1, 1954, President Dwight Eisenhower signed a law that moved for the creation of a U.S. Air Force Academy.", "Later that year, Colorado Springs was selected to host the new institution.", "From its establishment in 1955, until the construction of appropriate facilities in Colorado Springs was completed and opened in 1958, the Air Force Academy operated out of Lowry Air Force Base in Denver.", "With the opening of the Colorado Springs facility, the cadets moved to the new campus, though not in the full-kit march that some urban and campus legends suggest.", "The first class of Space Force officers from the Air Force Academy commissioned on April 18, 2020." ], [ "Military installations", "Fort CarsonPeterson Space Force BaseUnited States Air Force AcademyThe major military installations in Colorado include:* Buckley Space Force Base (1938–)** Air Reserve Personnel Center (1953–)* Fort Carson (U.S. Army 1942–) ** Piñon Canyon Maneuver Site (1983–)* Peterson Space Force Base (1942–)** Cheyenne Mountain Space Force Station (1961–)* Pueblo Chemical Depot (U.S. Army 1942–)* Schriever Space Force Base (1983–)* United States Air Force Academy (1954–)Former military posts in Colorado include:* Spanish Fort (Spanish Army 1819–1821)* Fort Massachusetts (U.S. Army 1852–1858)* Fort Garland (U.S. Army 1858–1883)* Camp Collins (U.S. Army 1862–1870)* Fort Logan (U.S. Army 1887–1946)* Colorado National Guard Armory (1913–1933)* Fitzsimons Army Hospital (U.S. Army 1918–1999)* Denver Medical Depot (U.S. Army 1925–1949)* Lowry Air Force Base (1938–1994)* Pueblo Army Air Base (1941–1948)* Rocky Mountain Arsenal (U.S. Army 1942–1992)* Camp Hale (U.S. Army 1942–1945)* La Junta Army Air Field (1942–1946)* Leadville Army Air Field (1943–1944)" ], [ "Government", "===State government=== State Executive Officers Office Name Party Governor Jared Polis Democratic Lieutenant Governor Dianne Primavera Democratic Secretary of State Jena Griswold Democratic Attorney General Phil Weiser Democratic Treasurer Dave Young DemocraticLike the federal government and all other U.S. states, Colorado's state constitution provides for three branches of government: the legislative, the executive, and the judicial branches.The Governor of Colorado heads the state's executive branch.", "The current governor is Jared Polis, a Democrat.", "Colorado's other statewide elected executive officers are the Lieutenant Governor of Colorado (elected on a ticket with the Governor), Secretary of State of Colorado, Colorado State Treasurer, and Attorney General of Colorado, all of whom serve four-year terms.The seven-member Colorado Supreme Court is the state's highest court, with seven justices.", "The Colorado Court of Appeals, with 22 judges, sits in divisions of three judges each.", "Colorado is divided into 22 judicial districts, each of which has a district court and a county court with limited jurisdiction.", "The state also has specialized water courts, which sit in seven distinct divisions around the state and which decide matters relating to water rights and the use and administration of water.The state legislative body is the Colorado General Assembly, which is made up of two houses – the House of Representatives and the Senate.", "The House has 65 members and the Senate has 35., the Democratic Party holds a 23 to 12 majority in the Senate and a 46 to 19 majority in the House.Most Coloradans are native to other states (nearly 60% according to the 2000 census), and this is illustrated by the fact that the state did not have a native-born governor from 1975 (when John David Vanderhoof left office) until 2007, when Bill Ritter took office; his election the previous year marked the first electoral victory for a native-born Coloradan in a gubernatorial race since 1958 (Vanderhoof had ascended from the Lieutenant Governorship when John Arthur Love was given a position in Richard Nixon's administration in 1973).Tax is collected by the Colorado Department of Revenue.====Politics==== Colorado registered voters Party Number of Voters Percentage Unaffiliated 1,812,690 46.88% Democratic 1,052,739 27.23% Republican 931,102 24.08% Libertarian 39,800 1.03% American Constitution 11,738 0.30% Green 8,513 0.22% Approval Voting 4,653 0.12% Unity 3,230 0.08% No Labels 1,341 0.03% Center 922 0.02% Total 3,866,728 100.00%Colorado was once considered a swing state, but has become a relatively safe blue state in both state and federal elections.", "In presidential elections, it had not been won until 2020 by double digits since 1984 and has backed the winning candidate in 9 of the last 11 elections.", "Coloradans have elected 17 Democrats and 12 Republicans to the governorship in the last 100 years.In presidential politics, Colorado was considered a reliably Republican state during the post-World War II era, voting for the Democratic candidate only in 1948, 1964, and 1992.However, it became a competitive swing state in the 1990s.", "Since the mid-2000s, it has swung heavily to the Democrats, voting for Barack Obama in 2008 and 2012, Hillary Clinton in 2016, and Joe Biden in 2020.Colorado politics exhibits a contrast between conservative cities such as Colorado Springs and Grand Junction, and liberal cities such as Boulder and Denver.", "Democrats are strongest in metropolitan Denver, the college towns of Fort Collins and Boulder, southern Colorado (including Pueblo), and several western ski resort counties.", "The Republicans are strongest in the Eastern Plains, Colorado Springs, Greeley, and far Western Colorado near Grand Junction.Colorado is represented by two members of the United States Senate:* Class 2, John Hickenlooper (Democratic), since 2021* Class 3, Michael Bennet (Democratic), since 2009Colorado is represented by eight members of the United States House of Representatives:* 1st district: Diana DeGette (Democratic), since 1997* 2nd district: Joe Neguse (Democratic), since 2019* 3rd district: Lauren Boebert (Republican), since 2021* 4th district: Ken Buck (Republican), since 2015* 5th district: Doug Lamborn (Republican), since 2007* 6th district: Jason Crow (Democratic), since 2019* 7th district: Brittany Pettersen (Democratic), since 2023* 8th district: Yadira Caraveo (Democratic), since 2023In a 2020 study, Colorado was ranked as the seventh easiest state for citizens to vote in.====Significant initiatives and legislation enacted in Colorado====Colorado was the first state in the union to enact, by voter referendum, a law extending suffrage to women.", "That initiative was approved by the state's voters on November 7, 1893.On the November 8, 1932, ballot, Colorado approved the repeal of alcohol prohibition more than a year before the Twenty-first Amendment to the United States Constitution was ratified.Colorado has banned, via C.R.S.", "section 12-6-302, the sale of motor vehicles on Sunday since at least 1953.In 1972 Colorado voters rejected a referendum proposal to fund the 1976 Winter Olympics, which had been scheduled to be held in the state.", "Denver had been chosen by the International Olympic Committee as the host city on May 12, 1970.In 1992, by a margin of 53 to 47 percent, Colorado voters approved an amendment to the state constitution (Amendment 2) that would have prevented any city, town, or county in the state from taking any legislative, executive or judicial action to recognize homosexuals or bisexuals as a protected class.", "In 1996, in a 6–3 ruling in ''Romer v. Evans'', the U.S. Supreme Court found that preventing protected status based upon homosexuality or bisexuality did not satisfy the Equal Protection Clause.In 2006, voters passed Amendment 43, which banned gay marriage in Colorado.", "That initiative was nullified by the U.S. Supreme Court's 2015 decision in ''Obergefell v. Hodges''.In 2012, voters amended the state constitution protecting the \"personal use\" of marijuana for adults, establishing a framework to regulate cannabis like alcohol.", "The first recreational marijuana shops in Colorado, and by extension the United States, opened their doors on January 1, 2014.On December 19, 2023, the Colorado Supreme Court ruled that Donald Trump was disqualified from the 2024 United States presidential election in part due to his alleged incitement of the January 6 United States Capitol attack." ], [ "Native American reservations", "The two Native American reservations remaining in Colorado are the Southern Ute Indian Reservation (1873; Ute dialect: ''Kapuuta-wa Moghwachi Núuchi-u'') and Ute Mountain Ute Indian Reservation (1940; Ute dialect: ''Wʉgama Núuchi'').", "The two abolished Indian reservations in Colorado were the Cheyenne and Arapaho Indian Reservation (1851–1870) and Ute Indian Reservation (1855–1873)." ], [ "Protected areas", "Colorado is home to 4 national parks, 9 national monuments, 3 national historic sites, 2 national recreation areas, 4 national historic trails, 1 national scenic trail, 11 national forests, 2 national grasslands, 44 national wildernesses, 3 national conservation areas, 8 national wildlife refuges, 3 national heritage areas, 26 national historic landmarks, 16 national natural landmarks, more than 1,500 National Register of Historic Places, 1 wild and scenic river, 42 state parks, 307 state wildlife areas, 93 state natural areas, 28 national recreation trails, 6 regional trails, and numerous other scenic, historic, and recreational areas." ], [ "See also", "*Bibliography of Colorado*Geography of Colorado*History of Colorado*Index of Colorado-related articles*List of Colorado-related lists**List of ships named the USS ''Colorado''*Outline of Colorado" ], [ "Footnotes" ], [ "References" ], [ "Further reading", "* ''Explore Colorado, A Naturalist's Handbook'', The Denver Museum of Natural History and Westcliff Publishers, 1995, for an excellent guide to the ecological regions of Colorado.", "* ''The Archeology of Colorado'', Revised Edition, E. Steve Cassells, Johnson Books, Boulder, Colorado, 1997, trade paperback, .", "* ''Chokecherry Places, Essays from the High Plains'', Merrill Gilfillan, Johnson Press, Boulder, Colorado, trade paperback, .", "* * ''The Tie That Binds'', Kent Haruf, 1984, hardcover, , a fictional account of farming in Colorado.", "* ''Railroads of Colorado: Your Guide to Colorado's Historic Trains and Railway Sites'', Claude Wiatrowski, Voyageur Press, 2002, hardcover, 160 pages, *" ], [ "External links", "===State government===* State of Colorado** Colorado Tourism Office** History Colorado*** Colorado Encyclopedia (partly sponsored by History Colorado)===Federal government===* Energy & Environmental Data for Colorado* USGS Colorado state facts, real-time, geographic, and other scientific resources of Colorado* United States Census Bureau** Colorado QuickFacts** 2000 Census of Population and Housing for Colorado* USDA ERS Colorado state facts* Colorado State Guide, from the Library of Congress===Other===* List of searchable databases produced by Colorado state agencies hosted by the American Library Association Government Documents Roundtable* Colorado County Evolution* Ask Colorado* Colorado Historic Newspapers Collection (CHNC)* Mountain and Desert Plants of Colorado and the Southwest,* Climate of Colorado * * * Holocene Volcano in Colorado (Smithsonian Institution Global Volcanism Program)" ] ]

[ [ "Carboniferous" ], [ "Introduction", "The '''Carboniferous''' ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period Ma (million years ago) to the beginning of the Permian Period, Ma.", "In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian and the later Pennsylvanian.The name ''Carboniferous'' means \"coal-bearing\", from the Latin (\"coal\") and (\"bear, carry\"), and refers to the many coal beds formed globally during that time.", "The first of the modern \"system\" names, it was coined by geologists William Conybeare and William Phillips in 1822, based on a study of the British rock succession.Carboniferous is the period during which both terrestrial animal and land plant life was well established.", "Stegocephalia (four-limbed vertebrates including true tetrapods), whose forerunners (tetrapodomorphs) had evolved from lobe-finned fish during the preceding Devonian period, became pentadactylous during the Carboniferous.", "The period is sometimes called the '''Age of Amphibians''' because of the diversification of early amphibians such as the temnospondyls, which became dominant land vertebrates, as well as the first appearance of amniotes including synapsids (the clade to which modern mammals belong) and sauropsids (which include modern reptiles and birds) during the late Carboniferous.", "Due to the raised atmospheric oxygen level, land arthropods such as arachnids (e.g.", "trigonotarbids and ''Pulmonoscorpius''), myriapods (e.g.", "''Arthropleura'') and insects (e.g.", "''Meganeura'') also underwent a major evolutionary radiation during the late Carboniferous.", "Vast swaths of forests and swamps covered the land, which eventually became the coal beds characteristic of the Carboniferous stratigraphy evident today.The later half of the period experienced glaciations, low sea level, and mountain building as the continents collided to form Pangaea.", "A minor marine and terrestrial extinction event, the Carboniferous rainforest collapse, occurred at the end of the period, caused by climate change." ], [ "Etymology and history", "The development of a Carboniferous chronostratigraphic timescale began in the late 18th century.", "The term \"Carboniferous\" was first used as an adjective by Irish geologist Richard Kirwan in 1799 and later used in a heading entitled \"Coal-measures or Carboniferous Strata\" by John Farey Sr. in 1811.Four units were originally ascribed to the Carboniferous, in ascending order, the Old Red Sandstone, Carboniferous Limestone, Millstone Grit and the Coal Measures.", "These four units were placed into a formalised Carboniferous unit by William Conybeare and William Phillips in 1822 and then into the Carboniferous System by Phillips in 1835.The Old Red Sandstone was later considered Devonian in age.The similarity in successions between the British Isles and Western Europe led to the development of a common European timescale with the Carboniferous System divided into the lower Dinantian, dominated by carbonate deposition and the upper Silesian with mainly siliciclastic deposition.", "The Dinantian was divided into the Tournaisian and Viséan stages.", "The Silesian was divided into the Namurian, Westphalian and Stephanian stages.", "The Tournaisian is the same length as the International Commission on Stratigraphy (ICS) stage, but the Viséan is longer, extending into the lower Serpukhovian.", "North American geologists recognised a similar stratigraphy but divided it into two systems rather than one.", "These are the lower carbonate-rich sequence of the Mississippian System and the upper siliciclastic and coal-rich sequence of the Pennsylvanian.", "The United States Geological Survey officially recognised these two systems in 1953.In Russia, in the 1840s British and Russian geologists divided the Carboniferous into the Lower, Middle and Upper series based on Russian sequences.", "In the 1890s these became the Dinantian, Moscovian and Uralian stages.", "The Serpukivian was proposed as part of the Lower Carboniferous, and the Upper Carboniferous was divided into the Moscovian and Gzhelian.", "The Bashkirian was added in 1934.In 1975, the ICS formally ratified the Carboniferous System, with the Mississippian and Pennsylvanian subsystems from the North American timescale, the Tournaisian and Visean stages from the Western European and the Serpukhovian, Bashkirian, Moscovian, Kasimovian and Gzhelian from the Russian.", "With the formal ratification of the Carboniferous System, the Dinantian, Silesian, Namurian, Westphalian and Stephanian became redundant terms, although the latter three are still in common use in Western Europe." ], [ "Geology", "=== Stratigraphy ===Stages can be defined globally or regionally.", "For global stratigraphic correlation, the ICS ratify global stages based on a Global Boundary Stratotype Section and Point (GSSP) from a single formation (a stratotype) identifying the lower boundary of the stage.", "Only the boundaries of the Carboniferous System and three of the stage bases are defined by global stratotype sections and points because of the complexity of the geology.", "The ICS subdivisions from youngest to oldest are as follows:Series/epochStage/ageLower boundaryPermianAsselian298.9 ±0.15 MaPennsylvanianUpperGzhelian303.7 ±0.1 MaKasimovian307.0 ±0.1 MaMiddleMoscovian315.2 ±0.2 MaLowerBashkirian323.2 ±0.4 MaMississippianUpperSerpukhovian330.9 ±0.2 MaMiddleVisean346.7 ±0.4 MaLowerTournaisian358.9 ±0.4 Ma==== Mississippian ====The Mississippian was proposed by Alexander Winchell in 1870 named after the extensive exposure of lower Carboniferous limestone in the upper Mississippi River valley.", "During the Mississippian, there was a marine connection between the Paleo-Tethys and Panthalassa through the Rheic Ocean resulting in the near worldwide distribution of marine faunas and so allowing widespread correlations using marine biostratigraphy.", "However, there are few Mississippian volcanic rocks, and so obtaining radiometric dates is difficult.The Tournaisian is defined by the first appearance of the conodont ''Siphonodella sulcata'' within the evolutionary lineage from ''Siphonodella praesulcata'' to ''Siphonodella sulcata''.", "This was ratified by the ICS in 1990.However, in 2006 further study revealed the presence of ''Siphonodella sulcata'' below the boundary, and the presence of ''Siphonodella'' ''praesulcata'' and ''Siphonodella sulcata'' together above a local unconformity.", "This means the evolution of one species to the other, the definition of the boundary, is not seen at the La Serre site making precise correlation difficult.Chart of regional subdivisions of the Carboniferous PeriodThe Viséan Stage was officially defined as the first black limestone in the Leffe facies at the Bastion Section in the Dinant Basin.", "These changes are now thought to be ecologically driven rather than caused by evolutionary change, and so this has not been used as the location for the GSSP.", "Instead, the GSSP for the base of the Visean is located in Bed 83 of the sequence of dark grey limestones and shales at the Pengchong section, Guangxi, southern China.", "It is defined by the first appearance of the fusulinid ''Eoparastaffella simplex'' in the evolutionary lineage ''Eoparastaffella ovalis – Eoparastaffella simplex'' and was ratified in 2009.The Serpukhovian Stage currently lacks a defined GSSP.", "The Visean-Serpukhovian boundary coincides with a major period of glaciation.", "The resulting sea level fall and climatic changes led to the loss of connections between marine basins and endemism of marine fauna across the Russian margin.", "This means changes in biota are environmental rather than evolutionary making wider correlation difficult.", "Work is underway in the Urals and Nashui, Guizhou Province, southwestern China for a suitable site for the GSSP with the proposed definition for the base of the Serpukhovian as the first appearance of conodont ''Lochriea ziegleri.", "''==== Pennsylvanian ====The Pennsylvanian was proposed by J.J.Stevenson in 1888, named after the widespread coal-rich strata found across the state of Pennsylvania.", "The closure of the Rheic Ocean and formation of Pangea during the Pennsylvanian, together with widespread glaciation across Gondwana led to major climate and sea level changes, which restricted marine fauna to particular geographic areas thereby reducing widespread biostratigraphic correlations.", "Extensive volcanic events associated with the assembling of Pangea means more radiometric dating is possible relative to the Mississippian.The GSSP for the base of the Pennsylvanian Subsystem and Bashkirian Stage is located at Arrow Canyon in Nevada, US and was ratified in 1996.It is defined by the first appearance of the conodont ''Declinognathodus noduliferus''.", "Arrow Canyon lay in a shallow, tropical seaway which stretched from Southern California to Alaska.", "The boundary is within a cyclothem sequence of transgressive limestones and fine sandstones, and regressive mudstones and brecciated limestones.The Moscovian currently lacks a defined GSSP.", "The fusulinid ''Aljutovella aljutovica'' can be used to define the base of the Moscovian across the northern and eastern margins of Pangea, however, it is restricted in geographic area, which means it cannot be used for global correlations.", "The first appearance of the conodonts ''Declinognathodus donetzianus'' or ''Idiognathoides postsulcatus'' have been proposed as a boundary marking species and potential sites in the Urals and Nashui, Guizhou Province, southwestern China are being considered.The Kasimovian covers a period of globally low sea level, which has resulted in disconformities within many sequences of this age.", "This has created difficulties in finding suitable marine fauna that can used to correlate boundaries worldwide.", "The Kasimovian currently lacks a defined GSSP; potential sites in the southern Urals, southwest USA and Nashui, Guizhou Province, southwestern China are being considered.The Gzhelian currently lacks a defined GSSP.", "The first appearance of the fusulinid ''Rauserites rossicus'' and ''Rauserites'' ''stuckenbergi'' can be used in the Boreal Sea and Paleo-Tethyan regions but not eastern Pangea or Panthalassa margins.", "Potential sites in the Urals and Nashui, Guizhou Province, southwestern China for the GSSP are being considered.The GSSP for the base of the Permian is located in the Aidaralash River valley near Aqtöbe, Kazakhstan and was ratified in 1996.The beginning of the stage is defined by the first appearance of the conodont ''Streptognathodus postfusus.", "''=== Cyclothems ===A cyclothem is a succession of non-marine and marine sedimentary rocks, deposited during a single sedimentary cycle, with an erosional surface at its base.", "Whilst individual cyclothems are often only metres to a few tens of metres thick, cyclothem sequences can be many hundreds to thousands of metres thick and contain tens to hundreds of individual cyclothems.", "Cyclothems were deposited along continental shelves where the very gentle gradient of the shelves meant even small changes in sea level led to large advances or retreats of the sea.", "Cyclothem lithologies vary from mudrock and carbonate-dominated to coarse siliciclastic sediment-dominated sequences depending on the paleo-topography, climate and supply of sediments to the shelf.Cliff section through the Serpukhovian Red Wharf Limestone Formation.", "A marine limestone at the base of the cliff is overlain by an orange-coloured fluvial sandstone.", "Subaerial exposure of the limestone during a period of falling sea level resulted in the formation of a karstic surface, which has then been infilled by the river sands.", "A thin, estuarine silty mudstone overlays the sandstone, which in turn overlain by a second marine limestone.The main period of cyclothem deposition occurred during the Late Paleozoic Ice Age from the Late Mississippian to early Permian, when the waxing and waning of ice sheets led to rapid changes in eustatic sea level.", "The growth of ice sheets led global sea levels to fall as water was lock away in glaciers.", "Falling sea levels exposed large tracts of the continental shelves across which river systems eroded channels and valleys and vegetation broke down the surface to form soils.", "The non-marine sediments deposited on this erosional surface form the base of the cyclothem.", "As sea levels began to rise, the rivers flowed through increasingly water-logged landscapes of swamps and lakes.", "Peat mires developed in these wet and oxygen-poor conditions, leading to coal formation.", "With continuing sea level rise, coastlines migrated landward and deltas, lagoons and esturaries developed; their sediments deposited over the peat mires.", "As fully marine conditions were established, limestones succeeded these marginal marine deposits.", "The limestones were in turn overlain by deep water black shales as maximum sea levels were reached.", "Ideally, this sequence would be reversed as sea levels began to fall again; however, sea level falls tend to be protracted, whilst sea level rises are rapid, ice sheets grow slowly but melt quickly.", "Therefore, the majority of a cyclothem sequence occurred during falling sea levels, when rates of erosion were high, meaning they were often periods of non-deposition.", "Erosion during sea level falls could also result in the full or partial removal of previous cyclothem sequences.", "Individual cyclothems are generally less than 10 m thick because the speed at which sea level rose gave only limited time for sediments to accumulate.During the Pennsylvanian, cyclothems were deposited in shallow, epicontinental seas across the tropical regions of Laurussia (present day western and central US, Europe, Russia and central Asia) and the North and South China cratons.", "The rapid sea levels fluctuations they represent correlate with the glacial cycles of the Late Paleozoic Ice Age.", "The advance and retreat of ice sheets across Gondwana followed a 100 kyr Milankovitch cycle, and so each cyclothem represents a cycle of sea level fall and rise over a 100 kyr period.=== Coal formation ===Hyden Formation over Pikeville Formation in the Pennsylvanian of Kentucky, US.", "The exposure has Pennsylvanian-aged cyclothemic sedimentary rocks of the Breathitt Group.", "The upper part of the roadcut is Hyden Formation, consisting of mixed siliciclastics and coal.", "The lower part is Pikeville Formation, also having mixed siliciclastics and coal.Coal forms when organic matter builds up in waterlogged, anoxic swamps, known as peat mires, and is then buried, compressing the peat into coal.", "The majority of Earth's coal deposits were formed during the late Carboniferous and early Permian.", "The plants from which they formed contributed to changes in the Carboniferous Earth's atmosphere, and the coal fueled the Industrial Revolution.During the Pennsylvanian, vast amounts of organic debris accumulated in the peat mires that formed across the low-lying, humid equatorial wetlands of the foreland basins of the Central Pangean Mountains in Laurussia, and around the margins of the North and South China cratons.", "During glacial periods, low sea levels exposed large areas of the continental shelves.", "Major river channels, up to several kilometres wide, stretched across these shelves feeding a network of smaller channels, lakes and peat mires.", "These wetlands were then buried by sediment as sea levels rose during interglacials.", "Continued crustal subsidence of the foreland basins and continental margins allowed this accumulation and burial of peat deposits to continue over millions of years resulting in the formation of thick and widespread coal formations.", "During the warm interglacials, smaller coal swamps with plants adapted to the temperate conditions formed on the Siberian craton and the western Australian region of Gondwana.There is ongoing debate as to why this peak in the formation of Earth's coal deposits occurred during the Carboniferous.", "The first theory, known as the delayed fungal evolution hypothesis, is that a delay between the development of trees with the wood fibre lignin and the subsequent evolution of lignin-degrading fungi gave a period of time where vast amounts of lignin-based organic material could accumulate.", "Genetic analysis of basidiomycete fungi, which have enzymes capable of breaking down lignin, supports this theory by suggesting this fungi evolved in the Permian.", "However, significant Mesozoic and Cenozoic coal deposits formed after lignin-digesting fungi had become well established, and fungal degradation of lignin may have already evolved by the end of the Devonian, even if the specific enzymes used by basidiomycetes had not.", "The second theory is that the geographical setting and climate of the Carboniferous were unique in Earth's history: the co-occurrence of the position of the continents across the humid equatorial zone, high biological productivity, and the low-lying, water-logged and slowly subsiding sedimentary basins that allowed the thick accumulation of peat were sufficient to account for the peak in coal formation." ], [ "Palaeogeography", "During the Carboniferous, there was an increased rate in tectonic plate movements as the supercontinent Pangea assembled.", "The continents themselves formed a near circle around the opening Paleo-Tethys Ocean, with the massive Panthalassic Ocean beyond.", "Gondwana covered the south polar region.", "To its northwest was Laurussia.", "These two continents slowly collided to form the core of Pangea.", "To the north of Laurussia lay Siberia and Amuria.", "To the east of Siberia, Kazakhstania, North China and South China formed the northern margin of the Paleo-Tethys, with Annamia laying to the south.Position of the continents in the late Carboniferous.", "Gondwana, Laurussia and Kazakhstania are already amalgamated as Pangea.", "Key: PA Panthalassa; S Siberia; AR Amuria; NC North China; SC South China; AN Annamia; PT Paleo-Tethys; red line approximate position of Variscan-Alleghanian-Ouachita Orogeny=== Variscan-Alleghanian-Ouachita orogeny ===The Central Pangean Mountains were formed during the Variscan-Alleghanian-Ouachita orogeny.", "Today their remains stretch over 10,000 km from the Gulf of Mexico in the east to Turkey in the west.", "The orogeny was caused by a series of continental collisions between Laurussia, Gondwana and the Armorican Terrane Assemblage (much of modern day Central and Western Europe including Iberia) as the Rheic Ocean closed and Pangea formed.", "This mountain building process began in the Middle Devonian and continued into the early Permian.The Armorican terranes rifted away from Gondwana during the Late Ordovician.", "As they drifted northwards the Rheic Ocean closed in front of them, and they began to collide with southeastern Laurussia in the Middle Devonian.", "The resulting Variscan orogeny involved a complex series of oblique collisions with associated metamorphism, igneous activity, and large-scale deformation between these terranes and Laurussia, which continued into the Carboniferous.During the mid Carboniferous, the South American sector of Gondwana collided obliquely with Laurussia's southern margin resulting in the Ouachita orogeny.", "The major strike-slip faulting that occurred between Laurussia and Gondwana extended eastwards into the Appalachian Mountains where early deformation in the Alleghanian orogeny was predominantly strike-slip.", "As the West African sector of Gondwana collided with Laurussia during the Late Pennsylvanian, deformation along the Alleghanian orogen became northwesterly-directed compression.=== Uralian orogeny ===The Uralian orogeny is a north–south trending fold and thrust belt that forms the western edge of the Central Asian Orogenic Belt.", "The Uralian orogeny began in the Late Devonian and continued, with some hiatuses, into the Jurassic.", "From the Late Devonian to early Carboniferous, the Magnitogorsk island arc, which lay between Kazakhstania and Laurussia in the Ural Ocean, collided with the passive margin of northeastern Laurussia (Baltica craton).", "The suture zone between the former island arc complex and the continental margin formed the Main Uralian Fault, a major structure that runs for more than 2,000 km along the orogen.", "Accretion of the island arc was complete by the Tournaisian, but subduction of the Ural Ocean between Kazakhstania and Laurussia continued until the Bashkirian when the ocean finally closed and continental collision began.", "Significant strike-slip movement along this zone indicates the collision was oblique.", "Deformation continued into the Permian and during the late Carboniferous and Permian the region was extensively intruded by granites.=== Laurussia ===The Laurussian continent was formed by the collision between Laurentia, Baltica and Avalonia during the Devonian.", "At the beginning of the Carboniferous it lay at low latitude in the southern hemisphere and drifted north during the Carboniferous, crossing the equator during the mid-to-late Carboniferous and reaching low latitudes in the northern hemisphere by the end of the Carboniferous.", "The Central Pangean Mountain drew in moist air from the Paleo-Tethys Ocean resulting in heavy precipitation and a tropical wetland environment.", "Extensive coal deposits developed within the cyclothem sequences that dominated the Pennsylvanian sedimentary basins associated with the growing orogenic belt.Subduction of the Panthalassic oceanic plate along its western margin resulted in the Antler orogeny in the Late Devonian to Early Mississippian.", "Further north along the margin, slab roll-back, beginning in the Early Mississippian, led to the rifting of the Yukon-Tanana terrane and the opening of the Slide Mountain Ocean.", "Along the northern margin of Laurussia, orogenic collapse of the Late Devonian to Early Mississippian Innuitian orogeny led to the development of the Sverdrup Basin.=== Gondwana ===Much of Gondwana lay in the southern polar region during the Carboniferous.", "As the plate moved, the South Pole drifted from southern Africa in the early Carboniferous to eastern Antarctica by the end of the period.", "Glacial deposits are widespread across Gondwana and indicate multiple ice centres and long-distance movement of ice.", "The northern to northeastern margin of Gondwana (northeast Africa, Arabia, India and northeastern West Australia) was a passive margin along the southern edge of the Paleo-Tethys with cyclothem deposition including, during more temperate intervals, coal swamps in Western Australia.", "The Mexican terranes along the northwestern Gondwana margin, were affected by the subduction of the Rheic Ocean.", "However, they lay to west of the Ouachita orogeny and were not impacted by continental collision but became part of the active margin of the Pacific.", "The Moroccan margin was affected by periods of widespread dextral strike-slip deformation, magmatism and metamorphism associated with the Variscan orogeny.Towards the end of the Carboniferous, extension and rifting across the northern margin of Gondwana led to the breaking away of the Cimmerian Terrane during the early Permian and the opening of the Neo-Tethys Ocean.", "Along the southeastern and southern margin of Gondwana (eastern Australia and Antarctica), northward subduction of Panthalassa continued.", "Changes in the relative motion of the plates resulted in the early Carboniferous Kanimblan Orogeny.", "Continental arc magmatism continued into the late Carboniferous and extended round to connect with the developing proto-Andean subduction zone along the western South American margin of Gondwana.=== Siberia and Amuria ===Shallow seas covered much of the Siberian craton in the early Carboniferous.", "These retreated as sea levels fell in the Pennsylvanian and as the continent drifted north into more temperate zones extensive coal deposits formed in the Kuznetsk Basin.", "The northwest to eastern margins of Siberia were passive margins along the Mongol-Okhotsk Ocean on the far side of which lay Amuria.", "From the mid Carboniferous, subduction zones with associated magmatic arcs developed along both margins of the ocean.The southwestern margin of Siberia was the site of a long lasting and complex accretionary orogen.", "The Devonian to early Carboniferous Siberian and South Chinese Altai accretionary complexes developed above an east-dipping subduction zone, whilst further south, the Zharma-Saur arc formed along the northeastern margin of Kazakhstania.", "By the late Carboniferous, all these complexes had accreted to the Siberian craton as shown by the intrusion of post-orogenic granites across the region.", "As Kazakhstania had already accreted to Laurussia, Siberia was effectively part of Pangea by 310 Ma, although major strike-slip movements continued between it and Laurussia into the Permian.=== Central and East Asia ===The Kazakhstanian microcontinent is composed of a series of Devonian and older accretionary complexes.", "It was strongly deformed during the Carboniferous as its western margin collided with Laurussia during the Uralian orogen and its northeastern margin collided with Siberia.", "Continuing strike-slip motion between Laurussia and Siberia led the formerly elongate microcontinent to bend into an orocline.During the Carboniferous, the Tarim craton lay along the northwestern edge of North China.", "Subduction along the Kazakhstanian margin of the Turkestan Ocean resulted in collision between northern Tarim and Kazakhstania during the mid Carboniferous as the ocean closed.", "The South Tian Shan fold and thrust belt, which extends over 2,000 km from Uzbekistan to northwest China, is the remains of this accretionary complex and forms the suture between Kazakhstania and Tarim.", "A continental magmatic arc above a south-dipping subduction zone lay along the northern North China margin, consuming the Paleoasian Ocean.", "Northward subduction of the Paleo-Tethys beneath the southern margins of North China and Tarim continued during the Carboniferous, with the South Qinling block accreted to North China during the mid to late Carboniferous.", "No sediments are preserved from the early Carboniferous in North China.", "However, bauxite deposits immediately above the regional mid Carboniferous unconformity indicate warm tropical conditions and are overlain by cyclothems including extensive coals.South China and Annamia (Southeast Asia) rifted from Gondwana during the Devonian.", "During the Carboniferous, they were separated from each other and North China by the Paleoasian Ocean with the Paleo-Tethys to the southwest and Panthalassa to the northeast.", "Cyclothem sediments with coal and evaporites were deposited across the passive margins that surrounded both continents." ], [ "Climate", "A reconstruction of life on a forest floor during the Pennsylvanian Period.", "The reptile is ''Edaphosaurus'', a pelycosaur.", "Plants are the seed ferns ''Neuropteris'' and ''Pectopteris'', the club mosses ''Lepidodendron'' and ''Sigillaria'', other plants include ''Cordaites'', ''Calamites'', climbing ferns, pond algae, and ''Sphenophyllum''.Average global temperatures in the early Carboniferous were high: approximately 20 °C (68 °F).", "However, cooling during the middle Carboniferous reduced average global temperatures to about 12 °C (54 °F).", "Atmospheric carbon dioxide levels fell from roughly 8 times the current level in the beginning, to a level similar to today's at the end of the period.", "Although it is often asserted that Carboniferous atmospheric oxygen concentrations were significantly higher than today, at around 30% of total atmospheric concentration, prehistoric atmospheric oxygen concentration estimates are highly uncertain, with other estimates suggesting that the amount of oxygen was actually lower than that present in today's atmosphere.The Carboniferous is considered part of the Late Palaeozoic Ice Age, which began in the latest Devonian with the formation of small glaciers in Gondwana.", "During the Tournaisian the climate warmed, before cooling, there was another warm interval during the Viséan, but cooling began again during the early Serpukhovian.", "At the beginning of the Pennsylvanian around 323 million years ago, glaciers began to form around the South Pole, which grew to cover a vast area of Gondwana.", "This area extended from the southern reaches of the Amazon basin and covered large areas of southern Africa, as well as most of Australia and Antarctica.", "Cyclothems, which began around 313 million years ago, and continue into the following Permian indicate that the size of the glaciers were controlled by Milankovitch cycles akin to recent ice ages, with glacial periods and interglacials.", "Deep ocean temperatures during this time were cold due to the influx of cold bottom waters generated by seasonal melting of the ice cap.The cooling and drying of the climate led to the Carboniferous rainforest collapse.", "Tropical rainforests fragmented and then were eventually devastated by climate change." ], [ "Geochemistry", "As the continents assembled to form Pangea, the growth of the Central Pangean Mountains led to increased weathering and carbonate sedimentation on the ocean floor, whilst the distribution of continents across the paleo-tropics meant vast areas of land were available for the spread of tropical rainforests.", "Together these two factors significantly increased CO2 drawdown from the atmosphere, lowering global temperatures, increasing ocean pH and triggering the Late Paleozoic Ice Age.", "The growth of the supercontinent also changed seafloor spreading rates and led to a decrease in the length and volume of mid-ocean ridge systems.=== Magnesium/calcium isotope ratios in seawater ===During the early Carboniferous, the Mg2+/Ca2+ ratio in seawater began to rise and by the Middle Mississippian aragonite seas had replaced calcite seas.", "The concentration of calcium in seawater is largely controlled by ocean pH, and as this increased the calcium concentration was reduced.", "At the same time, the increase in weathering, increased the amount of magnesium entering the marine environment.", "As magnesium is removed from seawater and calcium added along mid-ocean ridges where seawater reacts with the newly formed lithosphere, the reduction in length of mid-ocean ridge systems increased the Mg2+/Ca2+ ratio further.", "The Mg2+/Ca2+ ratio of the seas also affects the ability of organisms to biomineralize.", "The Carboniferous aragonite seas favoured those that secreted aragonite and the dominant reef builders of the time were aragonitic sponges and corals.=== Strontium isotopic composition of seawater ===The strontium isotopic composition (87Sr/86Sr) of seawater represents a mix of strontium derived from continental weathering which is rich in 87Sr and from mantle sources e.g.", "mid-ocean ridges, which are relatively depleted in 87Sr.", "87Sr/86Sr ratios above 0.7075 indicate continental weathering is the main source of 87Sr, whilst ratios below indicate mantle-derived sources are the principal contributor.87Sr/86Sr values varied through the Carboniferous, although they remained above 0.775, indicating continental weathering dominated as the source of 87Sr throughout.", "The 87Sr/86Sr during the Tournaisian was c. 0.70840, it decreased through the Visean to 0.70771 before increasing during the Serpukhovian to the lowermost Gzhelian where it plateaued at 0.70827, before decreasing again to 0.70814 at the Carboniferous-Permian boundary.", "These variations reflect the changing influence of weathering and sediment supply to the oceans of the growing Central Pangean Mountains.", "By the Serpukhovian basement rocks, such as granite, had been uplifted and exposed to weathering.", "The decline towards the end of the Carboniferous is interpreted as a decrease in continental weathering due to the more arid conditions.=== Oxygen and carbon isotope ratios in seawater ===Unlike Mg2+/Ca2+ and 87Sr/86Sr isotope ratios, which are consistent across the world's oceans at any one time, δ18O and δ13C preserved in the fossil record can be affected by regional factors.", "Carboniferous δ18O and δ13C records show regional differences between the South China open-water setting and the epicontinental seas of Laurussia.", "These differences are due to variations in seawater salinity and evaporation between epicontinental seas relative to the more open waters.", "However, large scale trends can still be determined.", "δ13C rose rapidly from c. 0 to 1‰ (parts per thousand) to c. 5 to 7‰ in the Early Mississippian and remained high for the duration of the Late Paleozoic Ice Age (c. 3–6‰) into the early Permian.", "Similarly from the Early Mississippian there was a long-term increase in δ18O values as the climate cooled.Both δ13C and δ18O records show significant global isotope changes (known as excursions) during the Carboniferous.", "The mid-Tournaisian positive δ13C and δ18O excursions lasted between 6 and 10 million years and were also accompanied by c. 6‰ positive excursion in organic matter δ15N values, a negative excursion in carbonate δ238U and a positive excursion in carbonate-associated sulphate δ34S.", "These changes in seawater geochemistry are interpreted as a decrease in atmospheric CO2 due to increased organic matter burial and widespread ocean anoxia triggering climate cooling and onset of glaciation.The Mississippian-Pennsylvanian boundary positive δ18O excursion occurred at the same time as global sea level falls and widespread glacial deposits across southern Gondwana, indicating climate cooling and ice build-up.", "The rise in 87Sr/86Sr just before the δ18O excursion suggests climate cooling in this case was caused by increased continental weathering of the growing Central Pangean Mountains and the influence of the orogeny on precipitation and surface water flow rather than increased burial of organic matter.", "δ13C values show more regional variation, and it is unclear whether there is a positive δ13C excursion or a readjustment from previous lower values.During the early Kasimovian there was a short (2 concentrations rapidly rose.", "There was a steady increase in arid conditions across tropical regions and a major reduction in the extent of tropical rainforests, as shown by the widespread loss of coal deposits from this time.", "The resulting reduction in productivity and burial of organic matter led to increasing atmospheric CO2 levels, which were recorded by a negative δ13C excursion and an accompanying, but smaller decrease in δ18O values." ], [ "Life", "===Plants===Etching depicting some of the most significant plants of the CarboniferousEarly Carboniferous land plants, some of which were preserved in coal balls, were very similar to those of the preceding Late Devonian, but new groups also appeared at this time.", "The main early Carboniferous plants were the Equisetales (horse-tails), Sphenophyllales (scrambling plants), Lycopodiales (club mosses), Lepidodendrales (scale trees), Filicales (ferns), Medullosales (informally included in the \"seed ferns\", an assemblage of a number of early gymnosperm groups) and the Cordaitales.", "These continued to dominate throughout the period, but during the late Carboniferous, several other groups, Cycadophyta (cycads), the Callistophytales (another group of \"seed ferns\"), and the Voltziales, appeared.lycopsid, probably ''Sigillaria'', with attached stigmarian rootslycopsid showing connection with bifurcating stigmarian rootsThe Carboniferous lycophytes of the order Lepidodendrales, which are cousins (but not ancestors) of the tiny club-moss of today, were huge trees with trunks 30 meters high and up to 1.5 meters in diameter.", "These included ''Lepidodendron'' (with its cone called Lepidostrobus), ''Anabathra'', ''Lepidophloios'' and ''Sigillaria''.", "The roots of several of these forms are known as Stigmaria.", "Unlike present-day trees, their secondary growth took place in the cortex, which also provided stability, instead of the xylem.", "The Cladoxylopsids were large trees, that were ancestors of ferns, first arising in the Carboniferous.The fronds of some Carboniferous ferns are almost identical with those of living species.", "Probably many species were epiphytic.", "Fossil ferns and \"seed ferns\" include ''Pecopteris'', ''Cyclopteris'', ''Neuropteris'', ''Alethopteris'', and ''Sphenopteris''; ''Megaphyton'' and ''Caulopteris'' were tree ferns.The Equisetales included the common giant form ''Calamites'', with a trunk diameter of 30 to and a height of up to .", "''Sphenophyllum'' was a slender climbing plant with whorls of leaves, which was probably related both to the calamites and the lycopods.", "''Cordaites'', a tall plant (6 to over 30 meters) with strap-like leaves, was related to the cycads and conifers; the catkin-like reproductive organs, which bore ovules/seeds, is called ''Cardiocarpus''.", "These plants were thought to live in swamps.", "True coniferous trees (''Walchia'', of the order Voltziales) appear later in the Carboniferous, and preferred higher drier ground.===Marine invertebrates===In the oceans the marine invertebrate groups are the Foraminifera, corals, Bryozoa, Ostracoda, brachiopods, ammonoids, hederelloids, microconchids and echinoderms (especially crinoids).", "The diversity of brachiopods and fusilinid foraminiferans, surged beginning in the Visean, continuing through the end of the Carboniferous, although cephalopod and nektonic conodont diversity declined.", "This evolutionary radiation was known as the Carboniferous-Earliest Permian Biodiversification Event.", "For the first time foraminifera took a prominent part in the marine faunas.", "The large spindle-shaped genus Fusulina and its relatives were abundant in what is now Russia, China, Japan, North America; other important genera include ''Valvulina'', ''Endothyra'', ''Archaediscus'', and ''Saccammina'' (the latter common in Britain and Belgium).", "Some Carboniferous genera are still extant.", "The first true priapulids appeared during this period.The microscopic shells of radiolarians are found in cherts of this age in the Culm of Devon and Cornwall, and in Russia, Germany and elsewhere.", "Sponges are known from spicules and anchor ropes, and include various forms such as the Calcispongea ''Cotyliscus'' and ''Girtycoelia'', the demosponge ''Chaetetes'', and the genus of unusual colonial glass sponges ''Titusvillia''.", "Both reef-building and solitary corals diversify and flourish; these include both rugose (for example, ''Caninia'', ''Corwenia'', ''Neozaphrentis''), heterocorals, and tabulate (for example, ''Chladochonus'', ''Michelinia'') forms.", "Conularids were well represented by ''Conularia''Bryozoa are abundant in some regions; the fenestellids including ''Fenestella'', ''Polypora'', and ''Archimedes'', so named because it is in the shape of an Archimedean screw.", "Brachiopods are also abundant; they include productids, some of which reached very large for brachiopods size and had very thick shells (for example, the -wide ''Gigantoproductus''), while others like ''Chonetes'' were more conservative in form.", "Athyridids, spiriferids, rhynchonellids, and terebratulids are also very common.", "Inarticulate forms include ''Discina'' and ''Crania''.", "Some species and genera had a very wide distribution with only minor variations.Annelids such as ''Serpulites'' are common fossils in some horizons.", "Among the mollusca, the bivalves continue to increase in numbers and importance.", "Typical genera include ''Aviculopecten'', ''Posidonomya'', ''Nucula'', ''Carbonicola'', ''Edmondia'', and ''Modiola''.", "Gastropods are also numerous, including the genera ''Murchisonia'', ''Euomphalus'', ''Naticopsis''.", "Nautiloid cephalopods are represented by tightly coiled nautilids, with straight-shelled and curved-shelled forms becoming increasingly rare.", "Goniatite ammonoids such as Aenigmatoceras are common.Trilobites are rarer than in previous periods, on a steady trend towards extinction, represented only by the proetid group.", "Ostracoda, a class of crustaceans, were abundant as representatives of the meiobenthos; genera included ''Amphissites'', ''Bairdia'', ''Beyrichiopsis'', ''Cavellina'', ''Coryellina'', ''Cribroconcha'', ''Hollinella'', ''Kirkbya'', ''Knoxiella'', and ''Libumella''.", "Crinoids were highly numerous during the Carboniferous, though they suffered a gradual decline in diversity during the Middle Mississippian.", "Dense submarine thickets of long-stemmed crinoids appear to have flourished in shallow seas, and their remains were consolidated into thick beds of rock.", "Prominent genera include ''Cyathocrinus'', ''Woodocrinus'', and ''Actinocrinus''.", "Echinoids such as ''Archaeocidaris'' and ''Palaeechinus'' were also present.", "The blastoids, which included the Pentreinitidae and Codasteridae and superficially resembled crinoids in the possession of long stalks attached to the seabed, attain their maximum development at this time.File:Aviculopecten subcardiformis01.JPG|''Aviculopecten subcardiformis''; a bivalve from the Logan Formation (lower Carboniferous) of Wooster, Ohio (external mold)File:LoganFauna011312.jpg|Bivalves (''Aviculopecten'') and brachiopods (''Syringothyris'') in the Logan Formation (lower Carboniferous) in Wooster, OhioFile:Syringothyris01.JPG|''Syringothyris'' sp.", "; a spiriferid brachiopod from the Logan Formation (lower Carboniferous) of Wooster, Ohio (internal mold)File:Palaeophycus01.JPG|''Palaeophycus'' ichnosp.", "; a trace fossil from the Logan Formation (lower Carboniferous) of Wooster, OhioFile:PlatyceratidMississippian.JPG|Crinoid calyx from the lower Carboniferous of Ohio with a conical platyceratid gastropod (''Palaeocapulus acutirostre'') attachedFile:Conulariid03.jpg|Conulariid from the lower Carboniferous of IndianaFile:Syringoporid.jpg|Tabulate coral (a syringoporid); Boone Limestone (lower Carboniferous) near Hiwasse, ArkansasFile:Typhloesus interpretation 2022.jpg|''Typhloesus'' was a bizarre invertebrate that lived in Montana.", "It is possibly a mollusk related to gastropods.File:Essexella asherae.JPG|''Essexella'' was a cnidarian that lived in Northern Illinois.", "It was long considered a scyphozoan, but is now regarded as a Sea anemoneFile:Concavicaris georgeorum.png|''Concavicaris'' was a long lasting genus of thylacocephalan arthropod that lived from the Devonian to the Carboniferous.File:Triproetus bonbon cropped.jpg|''Triproetus'' was a genus of proetid trilobite, which were the only order that survived the end-Devonian extinction File:Daidal.png|''Daidal'' was a basal species of Mantis shrimp (stomatopoda)File:Jeletzkya douglassae.jpg|''Jeletzkya'' was an early genus of coleoid cephalopod from northern Illinois File:Syllipsimopodi bideni.webp|''Syllipsimopodi'' was the earliest known vampyropod cephalopod, originating from Carboniferous rocks of Montana.===Freshwater and lagoonal invertebrates===Freshwater Carboniferous invertebrates include various bivalve molluscs that lived in brackish or fresh water, such as ''Anthraconaia'', ''Naiadites'', and ''Carbonicola''; diverse crustaceans such as ''Candona'', ''Carbonita'', ''Darwinula'', ''Estheria'', ''Acanthocaris'', ''Dithyrocaris'', and ''Anthrapalaemon''.", "The eurypterids were also diverse, and are represented by such genera as ''Adelophthalmus'', ''Megarachne'' (originally misinterpreted as a giant spider, hence its name) and the specialised very large ''Hibbertopterus''.", "Many of these were amphibious.", "Frequently a temporary return of marine conditions resulted in marine or brackish water genera such as ''Lingula'', ''Orbiculoidea'', and ''Productus'' being found in the thin beds known as marine bands.File:20210116 Megarachne hypothetical reconstruction.png|''Megarachne'' was a large freshwater eurypterid from South America that was originally misidentified as a spiderFile:Adelophthalmus irinae.png|''Adelophthalmus'' was the only genus of eurypterine eurypterid that survived past the DevonianFile:Hibbertopterus scouleri.jpg|Due to its large and compact shell, ''Hibbertopterus'' was one of if not the heaviest eurypterid in the fossil record=== Terrestrial invertebrates ===Fossil remains of air-breathing insects, myriapods and arachnids are known from the Carboniferous.", "Their diversity when they do appear, however, shows that these arthropods were both well-developed and numerous.", "Some arthropods grew to large sizes with the up to millipede-like ''Arthropleura'' being the largest-known land invertebrate of all time.", "Among the insect groups are the huge predatory Protodonata (griffinflies), among which was ''Meganeura'', a giant dragonfly-like insect and with a wingspan of ca.", "—the largest flying insect ever to roam the planet.", "Further groups are the Syntonopterodea (relatives of present-day mayflies), the abundant and often large sap-sucking Palaeodictyopteroidea, the diverse herbivorous Protorthoptera, and numerous basal Dictyoptera (ancestors of cockroaches).", "Many insects have been obtained from the coalfields of Saarbrücken and Commentry, and from the hollow trunks of fossil trees in Nova Scotia.", "Some British coalfields have yielded good specimens: ''Archaeoptilus'', from the Derbyshire coalfield, had a large wing with preserved part, and some specimens (''Brodia'') still exhibit traces of brilliant wing colors.", "In the Nova Scotian tree trunks land snails (''Archaeozonites'', ''Dendropupa'') have been found.File:Meganeura monyi au Museum de Toulouse.jpg|The late Carboniferous giant dragonfly-like insect ''Meganeura'' grew to wingspans of .File:20210116 Pulmonoscorpius kirktonensis.png|The gigantic ''Pulmonoscorpius'' from the early Carboniferous reached a length of up to .", "File:Arthropleura reconstruction.png|''Arthropleura'' was a giant millipede that fed on the Carboniferous plants.", "At 8 feet long, it was the largest terrestrial arthropod that ever lived.File:Mazothairos1.jpg|''Mazothairos'' was a large palaeodictyopteran insect from Mazon Creek.File:Helenodora inopinata.jpg|''Helenodora inopinata'', a stem-group onychophoran known from IndianaFile:Blattoidae - Fossil.JPG|A blattoid cockroach found in Carboniferous rocks of FranceFile:20201202 Maiocercus celticus.png|''Maiocercus'' was a trigonotarbid arachnid that lived in the United Kingdom around 310 million years ago.===Fish===Many fish inhabited the Carboniferous seas; predominantly Elasmobranchs (sharks and their relatives).", "These included some, like ''Psammodus'', with crushing pavement-like teeth adapted for grinding the shells of brachiopods, crustaceans, and other marine organisms.", "Other groups of elasmobranchs, like the ctenacanthiformes grew to large sizes, with some genera like ''Saivodus'' reaching around 6–9 meters (20–30 feet).", "Other fish had piercing teeth, such as the Symmoriida; some, the petalodonts, had peculiar cycloid cutting teeth.", "Most of the other cartilaginous fish were marine, but others like the Xenacanthida, and several genera like ''Bandringa'' invaded fresh waters of the coal swamps.", "Among the bony fish, the Palaeonisciformes found in coastal waters also appear to have migrated to rivers.", "Sarcopterygian fish were also prominent, and one group, the Rhizodonts, reached very large size.Most species of Carboniferous marine fish have been described largely from teeth, fin spines and dermal ossicles, with smaller freshwater fish preserved whole.", "Freshwater fish were abundant, and include the genera ''Ctenodus'', ''Uronemus'', ''Acanthodes'', ''Cheirodus'', and ''Gyracanthus''.", "Chondrichthyes (especially holocephalans like the Stethacanthids) underwent a major evolutionary radiation during the Carboniferous.", "It is believed that this evolutionary radiation occurred because the decline of the placoderms at the end of the Devonian caused many environmental niches to become unoccupied and allowed new organisms to evolve and fill these niches.", "As a result of the evolutionary radiation Carboniferous holocephalans assumed a wide variety of bizarre shapes including ''Stethacanthus'' which possessed a flat brush-like dorsal fin with a patch of denticles on its top.", "''Stethacanthus'' unusual fin may have been used in mating rituals.", "Other groups like the eugeneodonts filled in the niches left by large predatory placoderms.", "These fish were unique as they only possessed one row of teeth in their upper or lower jaws in the form of elaborate tooth whorls.", "The first members of the helicoprionidae, a family eugeneodonts that were characterized by the presence of one circular tooth whorl in the lower jaw, appeared during the early Carboniferous.", "Perhaps the most bizarre radiation of holocephalans at this time was that of the iniopterygiformes, an order of holocephalans that greatly resembled modern day flying fish that could have also \"flown\" in the water with their massive, elongated pectoral fins.", "They were further characterized by their large eye sockets, club-like structures on their tails, and spines on the tips of their fins.File:Stethacanthus BW.jpg|''Akmonistion'' of the Holocephali order Symmoriida roamed the oceans of the early Carboniferous.File:Falcatus.jpg|''Falcatus'' was a Carboniferous holocephalan, with a high degree of sexual dimorphism.File:Dracopristis hoffmanorum.png|''Dracopristis'' was a Ctenacanthiform elasmobranch from the late Carboniferous of New Mexico.File:Ornithoprion hertwigi.png|Ornithoprion was a small-sized Eugeneodont holocephalan that had an elongated lower jaw.File:Allenypterus montanus (Restoration) (cropped).jpg|''Allenypterus'' was a Coelacanth fish known from the Bear Gulch Limestone in Montana.File:†Phanerosteon phonax Carboniferous Bear Gulch.jpg|''Phanerosteon'' was a Bony fish belonging to the extinct order Palaeonisciformes.File:Edestus recon.png|''Edestus'' was a large eugeneodontid fish that possessed two tooth whorls in its mouthFile:Rhizodus.jpg|''Rhizodus'' was a large freshwater Rhizodont sarcopterygian from Europe and North America.File:Squatinactis NT small.jpg|''Squatinactis'', a genus of elasmobranch fish from Montana that possessed enlarged pectoral fins similar to modern angel sharksFile:Bandringa SW.png|''Bandringa'' is a bizarre elasmobranch fish that lived in Illinois, Ohio and Pennsylvania during the Moscovian stage.", "It superficially resembled a paddlefish, with an elongated upper rostrum.File:Iniopteryxrushlaui.JPG|''Iniopteryx'' was a holocephalan that lived in North America.", "This fish belonged to a group called the Iniopterygiformes, that possibly lived like flying fish.File:Listracanthus pectenatus reconstruction.jpg|''Listracanthus'' was an enigmatic chondrichthyean (potentially an elasmobranch) that possessed quill-like dermal denticles on its backFile:Strigilodus tollesonae-novataxa 2023-Hodnett Toomey Olson.jpg|Restoration of ''Strigilodus'', a petalodont holocephalan from the upper Carboniferous of Kentucky.===Tetrapods===Carboniferous amphibians were diverse and common by the middle of the period, more so than they are today; some were as long as 6 meters, and those fully terrestrial as adults had scaly skin.", "They included basal tetrapod groups classified in early books under the Labyrinthodontia.", "These had a long body, a head covered with bony plates, and generally weak or undeveloped limbs.", "The largest were over 2 meters long.", "They were accompanied by an assemblage of smaller amphibians included under the Lepospondyli, often only about long.", "Some Carboniferous amphibians were aquatic and lived in rivers (''Loxomma'', ''Eogyrinus'', ''Proterogyrinus''); others may have been semi-aquatic (''Ophiderpeton'', ''Amphibamus'', ''Hyloplesion'') or terrestrial (''Dendrerpeton'', ''Tuditanus'', ''Anthracosaurus'').The Carboniferous rainforest collapse slowed the evolution of amphibians who could not survive as well in the cooler, drier conditions.", "Amniotes, however, prospered because of specific key adaptations.", "One of the greatest evolutionary innovations of the Carboniferous was the amniote egg, which allowed the laying of eggs in a dry environment, as well as keratinized scales and claws, allowing for the further exploitation of the land by certain tetrapods.", "These included the earliest sauropsid reptiles (''Hylonomus''), and the earliest known synapsid (''Archaeothyris'').", "Synapsids quickly became huge and diversified in the Permian, only for their dominance to stop during the Mesozoic.", "Sauropsids (reptiles, and also, later, birds) also diversified but remained small until the Mesozoic, during which they dominated the land, as well as the water and sky, only for their dominance to stop during the Cenozoic.Reptiles underwent a major evolutionary radiation in response to the drier climate that preceded the rainforest collapse.", "By the end of the Carboniferous amniotes had already diversified into a number of groups, including several families of synapsid pelycosaurs, protorothyridids, captorhinids, saurians and araeoscelids.File:Pederpes22small.jpg|The amphibian-like ''Pederpes'', the most primitive tetrapod found in the Mississippian, and known from Scotland.File:Hylonomus BW.jpg|''Hylonomus'', the earliest sauropsid reptile, appeared in the Pennsylvanian, and is known from the Joggins Formation in Nova Scotia, and possibly New Brunswick.File:Petrolacosaurus BW.jpg|''Petrolacosaurus'', the earliest known diapsid reptile, lived during the late Carboniferous.File:Archaeothyris BW.jpg|''Archaeothyris'' is the oldest known synapsid, and is found in rocks from Nova Scotia.File:Coloraderpeton.jpg|''Coloraderpeton'' was a snake-like aïstopod tetrapodomorph from the late Carboniferous of Colorado.File:Crassigyrinus BW.jpg|''Crassygyrinus'' was a carnivorous stem-tetrapod from the early Carboniferous of Scotland.File:Microbrachis BW.jpg|''Microbrachis'' was a lepospondyl amphibian known from the Czech Republic.File:Amphibamus BW.jpg|''Amphibamus'' was a dissorophoid temnospondyl from the late Carboniferous of Illinois.===Fungi===As plants and animals were growing in size and abundance in this time, land fungi diversified further.", "Marine fungi still occupied the oceans.", "All modern classes of fungi were present in the late Carboniferous." ], [ "Extinction events", "===Romer's gap===The first 15 million years of the Carboniferous had very limited terrestrial fossils.", "While it has long been debated whether the gap is a result of fossilisation or relates to an actual event, recent work indicates there was a drop in atmospheric oxygen levels, indicating some sort of ecological collapse.", "The gap saw the demise of the Devonian fish-like ichthyostegalian labyrinthodonts and the rise of the more advanced temnospondyl and reptiliomorphan amphibians that so typify the Carboniferous terrestrial vertebrate fauna.===Carboniferous rainforest collapse===Before the end of the Carboniferous, an extinction event occurred.", "On land this event is referred to as the Carboniferous rainforest collapse.", "Vast tropical rainforests collapsed suddenly as the climate changed from hot and humid to cool and arid.", "This was likely caused by intense glaciation and a drop in sea levels.", "The new climatic conditions were not favorable to the growth of rainforest and the animals within them.", "Rainforests shrank into isolated islands, surrounded by seasonally dry habitats.", "Towering lycopsid forests with a heterogeneous mixture of vegetation were replaced by much less diverse tree fern dominated flora.", "Amphibians, the dominant vertebrates at the time, fared poorly through this event with large losses in biodiversity; reptiles continued to diversify through key adaptations that let them survive in the drier habitat, specifically the hard-shelled egg and scales, both of which retain water better than their amphibian counterparts." ], [ "See also", "* List of Carboniferous tetrapods* Important Carboniferous Lagerstätten** Granton Shrimp Bed; 359 mya; Edinburgh, Scotland** East Kirkton Quarry; c. 350 mya; Bathgate, Scotland** Bear Gulch Limestone; 324 mya; Montana, US** Mazon Creek; 309 mya; Illinois, US** Hamilton Quarry; 300 mya; Kansas, US* List of fossil sites" ], [ "References" ], [ "Sources", "** * * *** * * **** * * * * * * * * * * * * * *Rainer Zangerl and Gerard Ramon Case: ''Iniopterygia: a new order of Chondrichthyan fishes from the Pennsylvanian of North America.''", "Fieldiana Geology Memoirs, v. 6, Field Museum of Natural History, 1973 Biodiversity Heritage Library (Volltext, engl.", ")** * * * *" ], [ "External links", "* * Examples of Carboniferous Fossils* 60+ images of Carboniferous Foraminifera* Carboniferous (Chronostratography scale)" ] ]

[ [ "Comoros" ], [ "Introduction", "The '''Comoros''', officially the '''Union of the Comoros''', is an archipelagic country made up of three islands in Southeastern Africa, located at the northern end of the Mozambique Channel in the Indian Ocean.", "Its capital and largest city is Moroni.", "The religion of the majority of the population, and the official state religion, is Sunni Islam.", "Comoros proclaimed its independence from France on 6 July 1975.A member of the Arab League, it is the only country in the Arab world which is entirely in the Southern Hemisphere.", "It is a member state of the African Union, the ''Organisation internationale de la Francophonie'', the Organisation of Islamic Co-operation, and the Indian Ocean Commission.", "The country has three official languages: Shikomori, French and Arabic.At , the Comoros is the third-smallest African country by area.", "In 2019, its population was estimated to be 850,886.The sovereign state consists of three major islands and numerous smaller islands, all of the volcanic Comoro Islands with the exception of Mayotte.", "Mayotte voted against independence from France in a referendum in 1974, and continues to be administered by France as an overseas department.", "France has vetoed a United Nations Security Council resolution that would have affirmed Comorian sovereignty over the island.", "Mayotte became an overseas department and a region of France in 2011 following a referendum which was passed overwhelmingly.The Comoros were likely first settled by Austronesian/Malagasy peoples, Bantu speakers from East Africa, and seafaring Arab traders.", "It became part of the French colonial empire during the 19th century, before its independence in 1975.It has experienced more than 20 coups or attempted coups, with various heads of state assassinated.", "Along with this constant political instability, it has one of the worst levels of income inequality of any nation, and ranks in the medium quartile on the Human Development Index.", "Between 2009 and 2014, about 19% of the population lived below the international poverty line of US$1.90 a day by purchasing power parity." ], [ "Etymology", "The name \"Comoros\" derives from the Arabic word ''qamar'' (\"moon\")." ], [ "History", "=== Settlement ===A large dhow with lateen sail rigsA vanilla plantationAccording to mythology, a jinni (spirit) dropped a jewel, which formed a great circular inferno.", "This became the Karthala volcano, which created the island of Ngazidja (Grande Comore).", "King Solomon is also said to have visited the island accompanied by his queen Bilqis.The first attested human inhabitants of the Comoro Islands are now thought to have been Austronesian settlers travelling by boat from islands in Southeast Asia.", "These people arrived in the area no later than the eighth century AD, the date of the earliest known archaeological site, found on Mayotte, although settlement beginning in the first century has been postulated.Subsequent settlers came from the east coast of Africa, the Arabian Peninsula and the Persian Gulf, the Malay Archipelago, and Madagascar.", "Bantu-speaking settlers were present on the islands from the beginnings of settlement dates?, probably brought to the islands as slaves.Development of the Comoros is divided into phases.", "The earliest reliably recorded phase is the Dembeni phase (eighth to tenth centuries), during which there were several small settlements on each island.", "From the eleventh to the fifteenth centuries, trade with the island of Madagascar and merchants from the Swahili coast and the Middle East flourished, more villages were founded and existing villages grew.", "Settlers from the Arabian peninsula, particularly Hadhramaut, arrived during this period.=== Medieval Comoros ===According to legend, in 632, upon hearing of Islam, islanders are said to have dispatched an emissary, Mtswa-Mwindza, to Mecca—but by the time he arrived there, the Islamic prophet Muhammad had died.", "Nonetheless, after a stay in Mecca, he returned to Ngazidja, where he built a mosque in his home town of Ntsaweni, and led the gradual conversion of the islanders to Islam.In 933, the Comoros was referred to by Omani sailors as the Perfume Islands.Among the earliest accounts of East Africa, the works of Al-Masudi describe early Islamic trade routes, and how the coast and islands were frequently visited by Muslims including Persian and Arab merchants and sailors in search of coral, ambergris, ivory, tortoiseshell, gold and slaves.", "They also brought Islam to the people of the Zanj including the Comoros.", "As the importance of the Comoros grew along the East African coast, both small and large mosques were constructed.", "The Comoros are part of the Swahili cultural and economic complex and the islands became a major hub of trade and an important location in a network of trading towns that included Kilwa, in present-day Tanzania, Sofala (an outlet for Zimbabwean gold), in Mozambique, and Mombasa in Kenya.The Portuguese arrived in the Indian Ocean at the end of the 15th century and the first Portuguese visit to the islands seems to have been that of Vasco da Gama's second fleet in 1503.For much of the 16th century the islands provided provisions to the Portuguese fort at Mozambique and although there was no formal attempt by the Portuguese crown to take possession, a number of Portuguese traders settled and married local women.By the end of the 16th century local rulers on the African mainland were beginning to push back and, with the support of the Omani Sultan Saif bin Sultan they began to defeat the Dutch and the Portuguese.", "One of his successors, Said bin Sultan, increased Omani Arab influence in the region, moving his administration to nearby Zanzibar, which came under Omani rule.", "Nevertheless, the Comoros remained independent, and although the three smaller islands were usually politically unified, the largest island, Ngazidja, was divided into a number of autonomous kingdoms (''ntsi'').The islands were well placed to meet the needs of Europeans, initially supplying the Portuguese in Mozambique, then ships, particularly the English, on the route to India, and, later, slaves to the plantation islands in the Mascarenes.=== European contact and French colonisation ===French map of the Comores, 1747An 1808 map refers to the islands as \"Camora\".A public square, Moroni, 1908In the last decade of the 18th century, Malagasy warriors, mostly Betsimisaraka and Sakalava, started raiding the Comoros for slaves and the islands were devastated as crops were destroyed and the people were slaughtered, taken into captivity or fled to the African mainland: it is said that by the time the raids finally ended in the second decade of the 19th century only one man remained on Mwali.", "The islands were repopulated by slaves from the mainland, who were traded to the French in Mayotte and the Mascarenes.", "On the Comoros, it was estimated in 1865 that as much as 40% of the population consisted of slaves.France first established colonial rule in the Comoros by taking possession of Mayotte in 1841 when the Sakalava usurper sultan (also known as Tsy Levalo) signed the Treaty of April 1841, which ceded the island to the French authorities.", "After its annexation, France attempted to convert Mayotte into a sugar plantation colony.", "Meanwhile, Ndzwani (or Johanna as it was known to the British) continued to serve as a way station for English merchants sailing to India and the Far East, as well as American whalers, although the British gradually abandoned it following their possession of Mauritius in 1814, and by the time the Suez Canal opened in 1869 there was no longer any significant supply trade at Ndzwani.", "Local commodities exported by the Comoros were, in addition to slaves, coconuts, timber, cattle and tortoiseshell.", "British and American settlers, as well as the island's sultan, established a plantation-based economy that used about one-third of the land for export crops.", "In addition to sugar on Mayotte, ylang-ylang and other perfume plants, vanilla, cloves, coffee, cocoa beans, and sisal were introduced.In 1886, Mwali was placed under French protection by its Sultan Mardjani Abdou Cheikh.", "That same year, Sultan Said Ali of Bambao, one of the sultanates on Ngazidja, placed the island under French protection in exchange for French support of his claim to the entire island, which he retained until his abdication in 1910.In 1908 the four islands were unified under a single administration (''Colonie de Mayotte et dépendances'') and placed under the authority of the French colonial Governor-General of Madagascar.", "In 1909, Sultan Said Muhamed of Ndzwani abdicated in favour of French rule and in 1912 the protectorates were abolished and the islands administered as a single colony.", "Two years later the colony was abolished and the islands became a province of the colony of Madagascar.Agreement was reached with France in 1973 for the Comoros to become independent in 1978, despite the deputies of Mayotte voting for increased integration with France.", "A referendum was held on all four of the islands.", "Three voted for independence by large margins, while Mayotte voted against.", "On 6 July 1975, however, the Comorian parliament passed a unilateral resolution declaring independence.", "Ahmed Abdallah proclaimed the independence of the Comorian State (''État comorien''; دولة القمر) and became its first president.", "France did not recognise the new state until 31 December, and retained control of Mayotte.=== Independence (1975) ===Flag of the Comoros (1963–1975)Flag of the Comoros (1975–1978)Ikililou Dhoinine, President of the Comoros from 2011 to 2016The next 30 years were a period of political turmoil.", "On 3 August 1975, less than one month after independence, president Ahmed Abdallah was removed from office in an armed coup and replaced with United National Front of the Comoros (FNUK) member Said Mohamed Jaffar.", "Months later, in January 1976, Jaffar was ousted in favour of his Minister of Defence Ali Soilihi.The population of Mayotte voted against independence from France in three referendums during this period.", "The first, held on all the islands on 22 December 1974, won 63.8% support for maintaining ties with France on Mayotte; the second, held in February 1976, confirmed that vote with an overwhelming 99.4%, while the third, in April 1976, confirmed that the people of Mayotte wished to remain a French territory.", "The three remaining islands, ruled by President Soilihi, instituted a number of socialist and isolationist policies that soon strained relations with France.", "On 13 May 1978, Bob Denard, once again commissioned by the French intelligence service (SDECE), returned to overthrow President Soilihi and reinstate Abdallah with the support of the French, Rhodesian and South African governments.", "Ali Soilihi was captured and executed a few weeks later.In contrast to Soilihi, Abdallah's presidency was marked by authoritarian rule and increased adherence to traditional Islam and the country was renamed the Federal Islamic Republic of the Comoros (''République Fédérale Islamique des Comores''; جمهورية القمر الإتحادية الإسلامية).", "Bob Denard served as Abdallah's first advisor; nicknamed the \"Viceroy of the Comoros,\" he was sometimes considered the real strongman of the regime.", "Very close to South Africa, which financed his \"presidential guard,\" he allowed Paris to circumvent the international embargo on the apartheid regime via Moroni.", "He also set up from the archipelago a permanent mercenary corps, called upon to intervene at the request of Paris or Pretoria in conflicts in Africa.", "Abdallah continued as president until 1989 when, fearing a probable coup, he signed a decree ordering the Presidential Guard, led by Bob Denard, to disarm the armed forces.", "Shortly after the signing of the decree, Abdallah was allegedly shot dead in his office by a disgruntled military officer, though later sources claim an antitank missile was launched into his bedroom and killed him.", "Although Denard was also injured, it is suspected that Abdallah's killer was a soldier under his command.A few days later, Bob Denard was evacuated to South Africa by French paratroopers.", "Said Mohamed Djohar, Soilihi's older half-brother, then became president, and served until September 1995, when Bob Denard returned and attempted another coup.", "This time France intervened with paratroopers and forced Denard to surrender.", "The French removed Djohar to Reunion, and the Paris-backed Mohamed Taki Abdoulkarim became president by election.", "He led the country from 1996, during a time of labour crises, government suppression, and secessionist conflicts, until his death in November 1998.He was succeeded by Interim President Tadjidine Ben Said Massounde.The islands of Ndzwani and Mwali declared their independence from the Comoros in 1997, in an attempt to restore French rule.", "But France rejected their request, leading to bloody confrontations between federal troops and rebels.", "In April 1999, Colonel Azali Assoumani, Army Chief of Staff, seized power in a bloodless coup, overthrowing the Interim President Massounde, citing weak leadership in the face of the crisis.", "This was the Comoros' 18th coup, or attempted coup d'état since independence in 1975.Azali failed to consolidate power and reestablish control over the islands, which was the subject of international criticism.", "The African Union, under the auspices of President Thabo Mbeki of South Africa, imposed sanctions on Ndzwani to help broker negotiations and effect reconciliation.", "Under the terms of the Fomboni Accords, signed in December 2001 by the leaders of all three islands, the official name of the country was changed to the Union of the Comoros; the new state was to be highly decentralised and the central union government would devolve most powers to the new island governments, each led by a president.", "The Union president, although elected by national elections, would be chosen in rotation from each of the islands every five years.Azali stepped down in 2002 to run in the democratic election of the President of the Comoros, which he won.", "Under ongoing international pressure, as a military ruler who had originally come to power by force, and was not always democratic while in office, Azali led the Comoros through constitutional changes that enabled new elections.", "A ''Loi des compétences'' law was passed in early 2005 that defines the responsibilities of each governmental body, and is in the process of implementation.", "The elections in 2006 were won by Ahmed Abdallah Mohamed Sambi, a Sunni Muslim cleric nicknamed the \"Ayatollah\" for his time spent studying Islam in Iran.", "Azali honoured the election results, thus allowing the first peaceful and democratic exchange of power for the archipelago.Colonel Mohammed Bacar, a French-trained former gendarme elected President of Ndzwani in 2001, refused to step down at the end of his five-year mandate.", "He staged a vote in June 2007 to confirm his leadership that was rejected as illegal by the Comoros federal government and the African Union.", "On 25 March 2008 hundreds of soldiers from the African Union and the Comoros seized rebel-held Ndzwani, generally welcomed by the population: there have been reports of hundreds, if not thousands, of people tortured during Bacar's tenure.Some rebels were killed and injured, but there are no official figures.", "At least 11 civilians were wounded.", "Some officials were imprisoned.", "Bacar fled in a speedboat to Mayotte to seek asylum.", "Anti-French protests followed in the Comoros (see 2008 invasion of Anjouan).", "Bacar was eventually granted asylum in Benin.Since independence from France, the Comoros experienced more than 20 coups or attempted coups.Following elections in late 2010, former Vice-president Ikililou Dhoinine was inaugurated as president on 26 May 2011.Dhoinine is the first President of the Comoros from the island of Mwali.", "Following the 2016 elections, Azali Assoumani, from Ngazidja, became president for a third term.", "In 2018 Azali held a referendum on constitutional reform that would permit a president to serve two terms.", "The amendments passed, although the vote was widely contested and boycotted by the opposition, and in April 2019, and to widespread opposition, Azali was re-elected president to serve the first of potentially two five-year terms.", "In January 2020, the legislative elections in Comoros were dominated by President Azali Assoumani's party, the Convention for the Renewal of the Comoros, CRC.", "It took an overwhelming majority in the parliament.In 2021, Comoros signed and ratified the Treaty on the Prohibition of Nuclear Weapons, making it a nuclear-weapon-free state.", "and in 2023, Comoros was invited as a non-member guest to the G7 summit in Hiroshima.", "On 18 February 2023 the Comoros assumed the presidency of the African Union.In January 2024, President Azali Assoumani was re-elected with 63% of the vote in the disputed presidential election." ], [ "Geography", "A map of the ComorosThe Comoros is formed by Ngazidja (Grande Comore), Mwali (Mohéli) and Ndzwani (Anjouan), three major islands in the Comoros Archipelago, as well as many minor islets.", "The islands are officially known by their Comorian language names, though international sources still use their French names (given in parentheses above).", "The capital and largest city, Moroni, is located on Ngazidja.", "The archipelago is situated in the Indian Ocean, in the Mozambique Channel, between the African coast (nearest to Mozambique and Tanzania) and Madagascar, with no land borders.At , it is one of the smallest countries in the world.", "The Comoros also has claim to of territorial seas.", "The interiors of the islands vary from steep mountains to low hills.The areas and populations (at the 2017 Census) of the main islands are as follows: Name Area km2 PopulationCensus 2017 Mwali 21151,567 Ngazidja 1,024379,367 Ndzwani 424327,382 '''''Totals''''' 1,659758,316Ngazidja is the largest of the Comoros Archipelago, with an area of 1,024 km2.It is also the most recent island, and therefore has rocky soil.", "The island's two volcanoes, Karthala (active) and La Grille (dormant), and the lack of good harbours are distinctive characteristics of its terrain.", "Mwali, with its capital at Fomboni, is the smallest of the four major islands.", "Ndzwani, whose capital is Mutsamudu, has a distinctive triangular shape caused by three mountain chains – Shisiwani, Nioumakele and Jimilime – emanating from a central peak, ().Grande Comore landscapeThe islands of the Comoros Archipelago were formed by volcanic activity.", "Mount Karthala, an active shield volcano located on Ngazidja, is the country's highest point, at .", "It contains the Comoros' largest patch of disappearing rainforest.", "Karthala is currently one of the most active volcanoes in the world, with a minor eruption in May 2006, and prior eruptions as recently as April 2005 and 1991.In the 2005 eruption, which lasted from 17 to 19 April, 40,000 citizens were evacuated, and the crater lake in the volcano's caldera was destroyed.The Comoros also lays claim to the ''Îles Éparses'' or ''Îles éparses de l'océan indien'' (Scattered Islands in the Indian Ocean) – Glorioso Islands, comprising Grande Glorieuse, Île du Lys, Wreck Rock, South Rock, (three islets) and three unnamed islets – one of France's overseas districts.", "The Glorioso Islands were administered by the colonial Comoros before 1975, and are therefore sometimes considered part of the Comoros Archipelago.", "Banc du Geyser, a former island in the Comoros Archipelago, now submerged, is geographically located in the ''Îles Éparses'', but was annexed by Madagascar in 1976 as an unclaimed territory.", "The Comoros and France each still view the Banc du Geyser as part of the Glorioso Islands and, thus, part of its particular exclusive economic zone.=== Climate ===Comoros diver with fishThe climate is generally tropical and mild, and the two major seasons are distinguishable by their raininess.", "The temperature reaches an average of in March, the hottest month in the rainy season (called kashkazi/kaskazi meaning north monsoon, which runs from November to April), and an average low of in the cool, dry season (kusi (meaning south monsoon), which proceeds from May to October).", "The islands are rarely subject to cyclones.=== Biodiversity ===The Comoros constitute an ecoregion in their own right, Comoros forests.", "It had a 2018 Forest Landscape Integrity Index mean score of 7.69/10, ranking it 33rd globally out of 172 countries.In December 1952 a specimen of the West Indian Ocean coelacanth fish was re-discovered off the Comoros coast.", "The 66 million-year-old species was thought to have been long extinct until its first recorded appearance in 1938 off the South African coast.", "Between 1938 and 1975, 84 specimens were caught and recorded.===Protected areas===There are six national parks in the Comoros – Karthala, Coelacanth, and Mitsamiouli Ndroudi on Grande Comore, Mount Ntringui and Shisiwani on Anjouan, and Mohéli National Park on Mohéli.", "Karthala and Mount Ntrigui national parks cover the highest peaks on the respective islands, and Coelacanth, Mitsamiouli Ndroudi, and Shisiwani are marine national parks that protect the island's coastal waters and fringing reefs.", "Mohéli National Park includes both terrestrial and marine areas." ], [ "Government", "Moroni, capital of the Comoros, with the port and Badjanani MosquePolitics of the Comoros takes place in a framework of a unitary presidential republic, whereby the President of the Comoros is both head of state and head of government, and of a multi-party system.", "The Constitution of the Union of the Comoros was ratified by referendum on 23 December 2001, and the islands' constitutions and executives were elected in the following months.", "It had previously been considered a military dictatorship, and the transfer of power from Azali Assoumani to Ahmed Abdallah Mohamed Sambi in May 2006 was a watershed moment as it was the first peaceful transfer in Comorian history.Executive power is exercised by the government.", "Legislative power is vested in both the government and parliament.", "The preamble of the constitution guarantees an Islamic inspiration in governance, a commitment to human rights, and several specific enumerated rights, democracy, \"a common destiny\" for all Comorians.", "Each of the islands (according to Title II of the Constitution) has a great amount of autonomy in the Union, including having their own constitutions (or Fundamental Law), president, and Parliament.", "The presidency and Assembly of the Union are distinct from each of the islands' governments.", "The presidency of the Union rotates between the islands.", "Despite widespread misgivings about the durability of the system of presidential rotation, Ngazidja holds the current presidency rotation, and Azali is President of the Union; Ndzwani is in theory to provide the next president.=== Legal system ===The Comorian legal system rests on Islamic law, an inherited French (Napoleonic Code) legal code, and customary law (mila na ntsi).", "Village elders, kadis or civilian courts settle most disputes.", "The judiciary is independent of the legislative and the executive.", "The Supreme Court acts as a Constitutional Council in resolving constitutional questions and supervising presidential elections.", "As High Court of Justice, the Supreme Court also arbitrates in cases where the government is accused of malpractice.", "The Supreme Court consists of two members selected by the president, two elected by the Federal Assembly, and one by the council of each island.=== Political culture ===Around 80 percent of the central government's annual budget is spent on the country's complex administrative system which provides for a semi-autonomous government and president for each of the three islands and a rotating presidency for the overarching Union government.", "A referendum took place on 16 May 2009 to decide whether to cut down the government's unwieldy political bureaucracy.", "52.7% of those eligible voted, and 93.8% of votes were cast in approval of the referendum.", "Following the implementation of the changes, each island's president became a governor and the ministers became councillors.=== Foreign relations ===Azali Assoumani, President of the Comoros and Chair of the African Union, with Russian President Vladimir Putin at the Russia–Africa Summit in St. Petersburg on 28 July 2023In November 1975, the Comoros became the 143rd member of the United Nations.", "The new nation was defined as comprising the entire archipelago, although the citizens of Mayotte chose to become French citizens and keep their island as a French territory.The Comoros has repeatedly pressed its claim to Mayotte before the United Nations General Assembly, which adopted a series of resolutions under the caption \"Question of the Comorian Island of Mayotte\", opining that Mayotte belongs to the Comoros under the principle that the territorial integrity of colonial territories should be preserved upon independence.", "As a practical matter, however, these resolutions have little effect and there is no foreseeable likelihood that Mayotte will become ''de facto'' part of the Comoros without its people's consent.", "More recently, the Assembly has maintained this item on its agenda but deferred it from year to year without taking action.", "Other bodies, including the Organization of African Unity, the Movement of Non-Aligned Countries and the Organisation of Islamic Cooperation, have similarly questioned French sovereignty over Mayotte.", "To close the debate and to avoid being integrated by force in the Union of the Comoros, the population of Mayotte overwhelmingly chose to become an overseas department and a region of France in a 2009 referendum.", "The new status was effective on 31 March 2011 and Mayotte has been recognised as an outermost region by the European Union on 1 January 2014.This decision legally integrates Mayotte in the French Republic.The Comoros is a member of the United Nations, the African Union, the Arab League, the World Bank, the International Monetary Fund, the Indian Ocean Commission and the African Development Bank.", "On 10 April 2008, the Comoros became the 179th nation to accept the Kyoto Protocol to the United Nations Framework Convention on Climate Change.", "The Comoros signed the UN treaty on the Prohibition of Nuclear Weapons.", "Azali Assoumani, President of the Comoros and Chair of the African Union, attended the 2023 Russia–Africa Summit in Saint Petersburg.In May 2013 the Union of the Comoros became known for filing a referral to the Office of the Prosecutor of the International Criminal Court (ICC) regarding the events of \"the 31 May 2010 Israeli raid on the Humanitarian Aid Flotilla bound for the Gaza Strip\".", "In November 2014 the ICC Prosecutor eventually decided that the events did constitute war crimes but did not meet the gravity standards of bringing the case before ICC.The emigration rate of skilled workers was about 21.2% in 2000.=== Military ===The military resources of the Comoros consist of a small standing army and a 500-member police force, as well as a 500-member defence force.", "A defence treaty with France provides naval resources for protection of territorial waters, training of Comorian military personnel, and air surveillance.", "France maintains the presence of a few senior officers in the Comoros at government request, as well as a small maritime base and a Foreign Legion Detachment (DLEM) on Mayotte.Once the new government was installed in May–June 2011, an expert mission from UNREC (Lomé) came to the Comoros and produced guidelines for the elaboration of a national security policy, which were discussed by different actors, notably the national defence authorities and civil society.", "By the end of the programme in end March 2012, a normative framework agreed upon by all entities involved in SSR will have been established.", "This will then have to be adopted by Parliament and implemented by the authorities.=== Human rights ===Both male and female same-sex sexual acts are illegal in Comoros.", "Such acts are punished with up to five years imprisonment." ], [ "Economy", "GDP per capita development, since 1950The level of poverty in the Comoros is high, but \"judging by the international poverty threshold of $1.9 per person per day, only two out of every ten Comorians could be classified as poor, a rate that places the Comoros ahead of other low-income countries and 30 percentage points ahead of other countries in Sub-Saharan Africa.\"", "Poverty declined by about 10% between 2014 and 2018, and living conditions generally improved.", "Economic inequality remains widespread, with a major gap between rural and urban areas.", "Remittances through the sizable Comorian diaspora form a substantial part of the country's GDP and have contributed to decreases in poverty and increases in living standards.According to ILO's ILOSTAT statistical database, between 1991 and 2019 the unemployment rate as a percent of the total labor force ranged from 4.38% to 4.3%.", "An October 2005 paper by the Comoros Ministry of Planning and Regional Development, however, reported that \"registered unemployment rate is 14.3 percent, distributed very unevenly among and within the islands, but with marked incidence in urban areas.", "\"In 2019, more than 56% of the labor force was employed in agriculture, with 29% employed in industry and 14% employed in services.", "The islands' agricultural sector is based on the export of spices, including vanilla, cinnamon, and cloves, and thus susceptible to price fluctuations in the volatile world commodity market for these goods.", "The Comoros is the world's largest producer of ylang-ylang, a plant whose extracted essential oil is used in the perfume industry; some 80% of the world's supply comes from the Comoros.High population densities, as much as 1000 per square kilometre in the densest agricultural zones, for what is still a mostly rural, agricultural economy may lead to an environmental crisis in the near future, especially considering the high rate of population growth.", "In 2004 the Comoros' real GDP growth was a low 1.9% and real GDP per capita continued to decline.", "These declines are explained by factors including declining investment, drops in consumption, rising inflation, and an increase in trade imbalance due in part to lowered cash crop prices, especially vanilla.Fiscal policy is constrained by erratic fiscal revenues, a bloated civil service wage bill, and an external debt that is far above the HIPC threshold.", "Membership in the franc zone, the main anchor of stability, has nevertheless helped contain pressures on domestic prices.The Comoros has an inadequate transportation system, a young and rapidly increasing population, and few natural resources.", "The low educational level of the labour force contributes to a subsistence level of economic activity, high unemployment, and a heavy dependence on foreign grants and technical assistance.", "Agriculture contributes 40% to GDP and provides most of the exports.The government is struggling to upgrade education and technical training, to privatise commercial and industrial enterprises, to improve health services, to diversify exports, to promote tourism, and to reduce the high population growth rate.The Comoros is a member of the Organization for the Harmonization of Business Law in Africa (OHADA)." ], [ "Demographics", "A mosque in MoroniWith about 850,000 residents, the Comoros is one of the least-populous countries in the world, but its population density is high, with an average of .", "In 2001, 34% of the population was considered urban, but the urban population has since grown; in recent years rural population growth has been negative, while overall population growth is still relatively high.", "In 1958 the population was 183,133.Almost half the population of the Comoros is under the age of 15.Major urban centres include Moroni, Mitsamihuli, Foumbouni, Mutsamudu, Domoni, and Fomboni.", "There are between 200,000 and 350,000 Comorians in France.=== Ethnic groups ===The islands of the Comoros are 97.1% ethnically Comorian, which is a mixture of Bantu, Malagasy, and Arab people.", "Minorities include Makua and Indian (mostly Ismaili).", "There are recent immigrants of Chinese origin in Grande Comore (especially Moroni).", "Although most French left after independence in 1975, a small Creole community, descended from settlers from France, Madagascar and Réunion, lives in the Comoros.=== Languages ===The most common languages in the Comoros are the Comorian languages, collectively known as ''Shikomori''.", "They are related to Swahili, and the four different variants (Shingazidja, Shimwali, Shindzwani and Shimaore) are spoken on each of the four islands.", "Arabic and Latin scripts are both used, Arabic being the more widely used, and an official orthography has recently been developed for the Latin script.Arabic and French are also official languages, along with Comorian.", "Arabic is widely known as a second language, being the language of Quranic teaching.", "French is the administrative language and the language of most non-Quranic formal education.=== Religion ===A view of Domoni, Anjouan including mosqueSunni Islam is the dominant religion, followed by as much as 99% of the population.", "Comoros is the only Muslim-majority country in Southern Africa and one of the three southernmost Muslim-majority territories, along with Mayotte and the Australian territory of Cocos Islands.A minority of the population of the Comoros are Christian, both Catholic and Protestant denominations are represented, and most Malagasy residents are also Christian.", "Immigrants from metropolitan France are mostly Catholic.=== Health ===There are 15 physicians per 100,000 people.", "The fertility rate was 4.7 per adult woman in 2004.Life expectancy at birth is 67 for females and 62 for males.=== Education ===Almost all children attend Quranic schools, usually before, although increasingly in tandem with regular schooling.", "Children are taught about the Qur'an, and memorise it, and learn the Arabic script.", "Most parents prefer their children to attend Koran schools before moving on to the French-based schooling system.", "Although the state sector is plagued by a lack of resources, and the teachers by unpaid salaries, there are numerous private and community schools of relatively good standard.", "The national curriculum, apart from a few years during the revolutionary period immediately post-independence, has been very much based on the French system, both because resources are French and most Comorians hope to go on to further education in France.", "There have recently been moves to Comorianise the syllabus and integrate the two systems, the formal and the Quran schools, into one, thus moving away from the secular educational system inherited from France.Pre-colonization education systems in Comoros focused on necessary skills such as agriculture, caring for livestock and completing household tasks.", "Religious education also taught Islam.", "The education system underwent a transformation during colonization in the early 1900s which brought secular education based on the French system.", "This was mainly for children of the elite.", "After Comoros gained independence in 1975, the education system changed again.", "Funding for teachers' salaries was lost, and many went on strike.", "Thus, the public education system was not functioning between 1997 and 2001.Since gaining independence, the education system has also undergone a democratization and options exist for those other than the elite.", "Enrollment has also grown.In 2000, 44.2% of children aged 5 to 14 years were attending school.", "There is a general lack of facilities, equipment, qualified teachers, textbooks and other resources.", "Salaries for teachers are often so far in arrears that many refuse to work.Prior to 2000, students seeking a university education had to attend school outside of the country.", "However, in the early 2000s a university was created in the country.", "This served to help economic growth and to fight the \"flight\" of many educated people who were not returning to the islands to work.Comorian has no native script, but both the Arabic and Latin alphabets are used.", "In 2004, about 57 percent of the population was literate in the Latin script while more than 90 percent were literate in the Arabic script." ], [ "Culture", "Traditionally, women on Ndzwani wear red and white patterned garments called ''shiromani'', while on Ngazidja and Mwali colourful shawls called ''leso'' are worn.", "Many women apply a paste of ground sandalwood and coral called ''msindzano'' to their faces.", "Traditional male clothing is a long white shirt known as a ''nkandu'', and a bonnet called a ''kofia''.=== Marriage ===There are two types of marriages in Comoros, the little marriage (known as ''Mna daho'' on Ngazidja) and the customary marriage (known as ''ada'' on Ngazidja, ''harusi'' on the other islands).", "The little marriage is a simple legal marriage.", "It is small, intimate, and inexpensive, and the bride's dowry is nominal.", "A man may undertake a number of ''Mna daho'' marriages in his lifetime, often at the same time, a woman fewer; but both men and women will usually only undertake one ''ada'', or grand marriage, and this must generally be within the village.", "The hallmarks of the grand marriage are dazzling gold jewelry, two weeks of celebration and an enormous bridal dowry.", "Although the expenses are shared between both families as well as with a wider social circle, an ada wedding on Ngazidja can cost up to €50,000.Many couples take a lifetime to save for their ada, and it is not uncommon for a marriage to be attended by a couple's adult children.The ''ada'' marriage marks a man's transition in the Ngazidja age system from youth to elder.", "His status in the social hierarchy greatly increases, and he will henceforth be entitled to speak in public and participate in the political process, both in his village and more widely across the island.", "He will be entitled to display his status by wearing a ''mharuma'', a type of shawl, across his shoulders, and he can enter the mosque by the door reserved for elders, and sit at the front.", "A woman's status also changes, although less formally, as she becomes a \"mother\" and moves into her own house.", "The system is less formalised on the other islands, but the marriage is nevertheless a significant and costly event across the archipelago.", "The ''ada'' is often criticized because of its great expense, but at the same time it is a source of social cohesion and the main reason why migrants in France and elsewhere continue to send money home.", "Increasingly, marriages are also being taxed for the purposes of village development.=== Kinship and social structure ===Villagers in Bangwa Kuuni, NgazidjaComorian society has a bilateral descent system.", "Lineage membership and inheritance of immovable goods (land, housing) is matrilineal, passed in the maternal line, similar to many Bantu peoples who are also matrilineal, while other goods and patronymics are passed in the male line.", "However, there are differences between the islands, the matrilineal element being stronger on Ngazidja.=== Music ===Twarab music, imported from Zanzibar in the early 20th century, remains the most influential genre on the islands and is popular at ''ada'' marriages.=== Media ===There are two daily national newspapers published in the Comoros, the government-owned ''Al-Watwan'', and the privately owned ''La Gazette des Comores'', both published in Moroni.", "There are a number of smaller newsletters published on an irregular basis as well as a variety of news websites.", "The government-owned ORTC (Office de Radio et Télévision des Comores) provides national radio and television service.", "There is a TV station run by the Anjouan regional government, and regional governments on the islands of Grande Comore and Anjouan each operate a radio station.", "There are also a few independent and small community radio stations that operate on the islands of Grande Comore and Mohéli, and these two islands have access to Mayotte Radio and French TV." ], [ "See also", "*Index of Comoros-related articles*Outline of the Comoros" ], [ "Notes" ], [ "References", "=== Citations ====== Sources ===***This article incorporates text from the Library of Congress Country Studies, which is in the public domain." ], [ "External links", "* Union des Comores – Official government website** Tourism website * Embassy des Comores – The Federal and Islamic Republic of the Comoros in New York, United States*** Comoros from the BBC News* Key Development Forecasts for Comoros from International Futures" ] ]

[ [ "Critical philosophy" ], [ "Introduction", " The '''critical philosophy''' () movement, attributed to Immanuel Kant (1724–1804), sees the primary task of philosophy as criticism rather than justification of knowledge.", "Criticism, for Kant, meant judging as to the possibilities of knowledge before advancing to knowledge itself (from the Greek ''kritike (techne)'', or \"art of judgment\").", "The basic task of philosophers, according to this view, is not to establish and demonstrate theories about reality, but rather to subject all theories—including those about philosophy itself—to critical review, and measure their validity by how well they withstand criticism.", "\"Critical philosophy\" is also used as another name for Kant's philosophy itself.", "Kant said that philosophy's proper inquiry is not about what is out there in reality, but rather about the character and foundations of experience itself.", "We must first judge how human reason works, and within what limits, so that we can afterwards correctly apply it to sense experience and determine whether it can be applied at all to metaphysical objects.The principal three sources on which the critical philosophy is based are the three critiques, namely ''Critique of Pure Reason'', ''Critique of Practical Reason'' and ''Critique of Judgement'', published between 1781 and 1790 and mostly concerned, respectively, with metaphysics, ethics and aesthetics." ], [ "See also", "*Critical idealism*Critical thinking*Charles Bernard Renouvier*Léon Brunschvicg" ], [ "References", "* ''Stanford Encyclopedia of Philosophy'': Immanuel Kant" ] ]

[ [ "China" ], [ "Introduction", "'''China''' (), officially the '''People's Republic of China''' ('''PRC'''), is a country in East Asia.", "With a population exceeding 1.4 billion, it is the world's second-most-populous country.", "China spans the equivalent of five time zones and borders fourteen countries by land.", "With an area of nearly , it is the third-largest country by total land area.", "The country is divided into 22 provinces, five autonomous regions, four municipalities, and two semi-autonomous special administrative regions.", "Beijing is the national capital, while Shanghai is the most populous city and largest financial center.The region has been inhabited since the Paleolithic era.", "Early Chinese dynasties, such as the Shang and the Zhou, emerged in the basin of the Yellow River before the late second millennium BCE.", "The eighth to third centuries BCE saw a breakdown in Zhou authority and significant conflict, as well as the emergence of literature, philosophy, and historiograpahy.", "In 221 BCE, China was unified under an emperor for the first time where appointed non-hereditary officials rules counties instead aristocracy, ushering in more than two millennia in which China was governed by imperial dynasties, including the Qin, Han, Tang, Yuan, Ming, and Qing.", "With the invention of gunpowder and paper, the establishment of the Silk Road, and the building of the Great Wall, Chinese culture—including languages, traditions, architecture, philosophy and more—flourished and has heavily influenced East Asia and beyond.In 1912, after decades of struggle, the monarchy was overthrown and the Republic of China (ROC) was established.", "Despite ultimate winning in the Second Sino-Japanese War, as a part of the World War II, numerous atrocities such as the Nanjing Massacre torched the land.", "The Chinese Communist Party (CCP) fought Kuomintang-led government on-and-off since 1927 and in 1949 CCP established control over most of ROC's territory and the Kuomintang fled to Taiwan, the country is split with both sides claiming to be the sole legitimate government of China.", "Early communist rule saw two major projects: the Great Leap Forward, which resulted in a sharp economic decline and massive famine; and the Cultural Revolution, a movement to purge all non-communist elements of Chinese society that led to mass violence and persecution while its military became involved in the Korean War.", "Economic reforms that begin in 1978 moved the country away from planned economics, but political reforms were cut short by the 1989 Tiananmen Square protests and massacre.", "Economic reform continued to strengthen the nation's economy in the following decades while raising China's standard of living significantly.China is a unitary one-party socialist republic led by the CCP.", "It is a founding member of the United Nations (UN), and one of the five permanent members of the UN Security Council.", "It is a founding member of several multilateral and regional organizations such as the AIIB, the Silk Road Fund, the New Development Bank, and the RCEP.", "It is a member of the BRICS, the G20, APEC, the SCO, and the East Asia Summit.", "Making up around one-fifth of the world economy, China is the world's largest economy by GDP at purchasing power parity, the second-largest economy by nominal GDP, and the second-wealthiest country, albeit ranking poorly in measures of democracy, and human rights.", "The country is one of the fastest-growing major economies and is the world's largest manufacturer and exporter, as well as the second-largest importer, although its economic growth has slowed greatly in the 2020s.", "China is a nuclear-weapon state with the world's largest standing army by military personnel and the second-largest defense budget.", "China is a great power, a regional power and is widely considered to be a potential superpower." ], [ "Etymology", "''China'' (today's Guangdong), ''Mangi'' (inland of ''Xanton''), and ''Cataio'' (inland of ''China'' and ''Chequan'', and including the capital ''Cambalu'', ''Xandu'', and a marble bridge) are all shown as separate regions on this 1570 map by Abraham Ortelius.The word \"China\" has been used in English since the 16th century; however, it was not used by the Chinese themselves during this period.", "Its origin has been traced through Portuguese, Malay, and Persian back to the Sanskrit word , used in ancient India.", "\"China\" appears in Richard Eden's 1555 translation of the 1516 journal of the Portuguese explorer Duarte Barbosa.", "Barbosa's usage was derived from Persian (), which in turn derived from Sanskrit ().", "was first used in early Hindu scripture, including the ''Mahabharata'' (5th century BCE) and the ''Laws of Manu'' (2nd century BCE).", "In 1655, Martino Martini suggested that the word China is derived ultimately from the name of the Qin dynasty (221–206 BCE).", "Although use in Indian sources precedes this dynasty, this derivation is still given in various sources.", "The origin of the Sanskrit word is a matter of debate.", "Alternative suggestions include the names for Yelang and the Jing or Chu state.The official name of the modern state is the \"People's Republic of China\" ().", "The shorter form is \"China\" (), from ('central') and ('state'), a term which developed under the Western Zhou dynasty in reference to its royal demesne.", "It was used in official documents as an synonym for the state under the Qing.", "The name ''Zhongguo'' is also translated as in English.", "China is sometimes referred to as \"mainland China\" or \"the Mainland\" when distinguishing it from the Republic of China." ], [ "History", "=== Prehistory ===10,000-year-old pottery, Xianren Cave culture (18000–7000 BCE)Archaeological evidence suggests that early hominids inhabited China 2.25 million years ago.", "The hominid fossils of Peking Man, a ''Homo erectus'' who used fire, have been dated to between 680,000 and 780,000 years ago.", "The fossilized teeth of ''Homo sapiens'' (dated to 125,000–80,000 years ago) have been discovered in Fuyan Cave.", "Chinese proto-writing existed in Jiahu around 6600 BCE, at Damaidi around 6000 BCE, Dadiwan from 5800 to 5400 BCE, and Banpo dating from the 5th millennium BCE.", "Some scholars have suggested that the Jiahu symbols (7th millennium BCE) constituted the earliest Chinese writing system.=== Early dynastic rule ===Yinxu, the ruins of the capital of the late Shang dynasty (14th century BCE)According to Chinese tradition, the first dynasty was the Xia, which emerged around 2100 BCE.", "The Xia dynasty marked the beginning of China's political system based on hereditary monarchies, or dynasties.", "The Xia dynasty was considered mythical by historians until scientific excavations found early Bronze Age sites at Erlitou in 1959.It remains unclear whether these sites are the remains of the Xia dynasty or of another culture from the same period.", "The succeeding Shang dynasty is the earliest to be confirmed by contemporary records.", "The Shang ruled the plain of the Yellow River in eastern China from the 17th to the 11th century BCE.", "Their oracle bone script (from BCE) represents the oldest form of Chinese writing yet found and is a direct ancestor of modern Chinese characters.The Shang was conquered by the Zhou, who ruled between the 11th and 5th centuries BCE, though centralized authority was slowly eroded by feudal warlords.", "Some principalities eventually emerged from the weakened Zhou and continually waged war with each other during the 300-year Spring and Autumn period.", "By the time of the Warring States period of the 5th–3rd centuries BCE, there were seven major powerful states left.=== Imperial China ===expansion of Han dynasty in the 2nd century BC|thumb|upright=1.1The Warring States period ended in 221 BCE after the state of Qin conquered the other six kingdoms, reunited China and established the dominant order of autocracy.", "King Zheng of Qin proclaimed himself the Emperor of the Qin dynasty, becoming the first emperor of a unified China.", "He enacted Qin's legalist reforms, notably the forced standardization of Chinese characters, measurements, road widths, and currency.", "His dynasty also conquered the Yue tribes in Guangxi, Guangdong, and Northern Vietnam.", "The Qin dynasty lasted only fifteen years, falling soon after the First Emperor's death, as his harsh authoritarian policies led to widespread rebellion.Following a widespread civil war during which the imperial library was burned, the Han dynasty emerged to rule China between 206 BCE and CE 220, creating a cultural identity among its populace still remembered in the ethnonym of the modern Han Chinese.", "The Han expanded the empire's territory considerably, with military campaigns reaching Central Asia, Mongolia, Korea, and Yunnan, and the recovery of Guangdong and northern Vietnam from Nanyue.", "Han involvement in Central Asia and Sogdia helped establish the land route of the Silk Road, replacing the earlier path over the Himalayas to India.", "Han China gradually became the largest economy of the ancient world.", "Despite the Han's initial decentralization and the official abandonment of the Qin philosophy of Legalism in favor of Confucianism, Qin's legalist institutions and policies continued to be employed by the Han government and its successors.After the end of the Han dynasty, a period of strife known as Three Kingdoms followed, at the end of which Wei was swiftly overthrown by the Jin dynasty.", "The Jin fell to civil war upon the ascension of a developmentally disabled emperor; the Five Barbarians then rebelled and ruled northern China as the Sixteen States.", "The Xianbei unified them as the Northern Wei, whose Emperor Xiaowen reversed his predecessors' apartheid policies and enforced a drastic sinification on his subjects.", "In the south, the general Liu Yu secured the abdication of the Jin in favor of the Liu Song.", "The various successors of these states became known as the Northern and Southern dynasties, with the two areas finally reunited by the Sui in 581.The Sui restored the Han to power through China, reformed its agriculture, economy and imperial examination system, constructed the Grand Canal, and patronized Buddhism.", "However, they fell quickly when their conscription for public works and a failed war in northern Korea provoked widespread unrest.protectorates|thumb|upright=1.1Under the succeeding Tang and Song dynasties, Chinese economy, technology, and culture entered a golden age.", "The Tang dynasty retained control of the Western Regions and the Silk Road, which brought traders to as far as Mesopotamia and the Horn of Africa, and made the capital Chang'an a cosmopolitan urban center.", "However, it was devastated and weakened by the An Lushan rebellion in the 8th century.", "In 907, the Tang disintegrated completely when the local military governors became ungovernable.", "The Song dynasty ended the separatist situation in 960, leading to a balance of power between the Song and the Liao dynasty.", "The Song was the first government in world history to issue paper money and the first Chinese polity to establish a permanent navy which was supported by the developed shipbuilding industry along with the sea trade.Between the 10th and 11th century CE, the population of China doubled to around 100 million people, mostly because of the expansion of rice cultivation in central and southern China, and the production of abundant food surpluses.", "The Song dynasty also saw a revival of Confucianism, in response to the growth of Buddhism during the Tang, and a flourishing of philosophy and the arts, as landscape art and porcelain were brought to new levels of complexity.", "However, the military weakness of the Song army was observed by the Jin dynasty.", "In 1127, Emperor Huizong of Song and the capital Bianjing were captured during the Jin–Song Wars.", "The remnants of the Song retreated to southern China.China's first emperor, Qin Shi Huang, is famed for having united the Warring States' walls to form the Great Wall of China.", "Most of the present structure, however, dates to the Ming dynasty|thumb|upright=1.1The Mongol conquest of China began in 1205 with the gradual conquest of Western Xia by Genghis Khan, who also invaded Jin territories.", "In 1271, the Mongol leader Kublai Khan established the Yuan dynasty, which conquered the last remnant of the Song dynasty in 1279.Before the Mongol invasion, the population of Song China was 120 million citizens; this was reduced to 60 million by the time of the census in 1300.A peasant named Zhu Yuanzhang overthrew the Yuan in 1368 and founded the Ming dynasty as the Hongwu Emperor.", "Under the Ming dynasty, China enjoyed another golden age, developing one of the strongest navies in the world and a rich and prosperous economy amid a flourishing of art and culture.", "It was during this period that admiral Zheng He led the Ming treasure voyages throughout the Indian Ocean, reaching as far as East Africa.In the early Ming dynasty, China's capital was moved from Nanjing to Beijing.", "With the budding of capitalism, philosophers such as Wang Yangming critiqued and expanded Neo-Confucianism with concepts of individualism and equality of four occupations.", "The scholar-official stratum became a supporting force of industry and commerce in the tax boycott movements, which, together with the famines and defense against Japanese invasions of Korea (1592–1598) and Later Jin incursions led to an exhausted treasury.", "In 1644, Beijing was captured by a coalition of peasant rebel forces led by Li Zicheng.", "The Chongzhen Emperor committed suicide when the city fell.", "The Manchu Qing dynasty, then allied with Ming dynasty general Wu Sangui, overthrew Li's short-lived Shun dynasty and subsequently seized control of Beijing, which became the new capital of the Qing dynasty.The upright=1.1The Qing dynasty, which lasted from 1644 until 1912, was the last imperial dynasty of China.", "The Ming-Qing transition (1618–1683) cost 25 million lives, but the Qing appeared to have restored China's imperial power and inaugurated another flowering of the arts.", "After the Southern Ming ended, the further conquest of the Dzungar Khanate added Mongolia, Tibet and Xinjiang to the empire.", "Meanwhile, China's population growth resumed and shortly began to accelerate.", "It is commonly agreed that pre-modern China's population experienced two growth spurts, one during the Northern Song period (960–1127), and other during the Qing period (around 1700–1830).", "By the High Qing era China was possibly the most commercialized country in the world, and imperial China experienced a second commercial revolution by the end of the 18th century.", "On the other hand, the centralized autocracy was strengthened in part to suppress anti-Qing sentiment with the policy of valuing agriculture and restraining commerce, like the ''Haijin'' during the early Qing period and ideological control as represented by the literary inquisition, causing some social and technological stagnation.=== Fall of the Qing dynasty ===The Eight-Nation Alliance invaded China to defeat the anti-foreign Boxers and their Qing backers.", "The image shows a celebration ceremony inside the Chinese imperial palace, the Forbidden City after the signing of the Boxer Protocol in 1901.In the mid-19th century, the Opium Wars with Britain and France forced China to pay compensation, open treaty ports, allow extraterritoriality for foreign nationals, and cede Hong Kong to the British under the 1842 Treaty of Nanking, the first of what have been termed as the \"unequal treaties\".", "The First Sino-Japanese War (1894–1895) resulted in Qing China's loss of influence in the Korean Peninsula, as well as the cession of Taiwan to Japan.", "The Qing dynasty also began experiencing internal unrest in which tens of millions of people died, especially in the White Lotus Rebellion, the failed Taiping Rebellion that ravaged southern China in the 1850s and 1860s and the Dungan Revolt (1862–1877) in the northwest.", "The initial success of the Self-Strengthening Movement of the 1860s was frustrated by a series of military defeats in the 1880s and 1890s.In the 19th century, the great Chinese diaspora began.", "Losses due to emigration were added to by conflicts and catastrophes such as the Northern Chinese Famine of 1876–1879, in which between 9 and 13 million people died.", "The Guangxu Emperor drafted a reform plan in 1898 to establish a modern constitutional monarchy, but these plans were thwarted by the Empress Dowager Cixi.", "The ill-fated anti-foreign Boxer Rebellion of 1899–1901 further weakened the dynasty.", "Although Cixi sponsored a program of reforms known as the late Qing reforms, the Xinhai Revolution of 1911–1912 ended the Qing dynasty and established the Republic of China.", "Puyi, the last Emperor, abdicated in 1912.=== Establishment of the Republic and World War II ===On 1 January 1912, the Republic of China was established, and Sun Yat-sen of the Kuomintang (KMT) was proclaimed provisional president.", "In March 1912, the presidency was given to Yuan Shikai, a former Qing general who in 1915 proclaimed himself Emperor of China.", "In the face of popular condemnation and opposition from his own Beiyang Army, he was forced to abdicate and re-establish the republic in 1916.After Yuan Shikai's death in 1916, China was politically fragmented.", "Its Beijing-based government was internationally recognized but virtually powerless; regional warlords controlled most of its territory.", "Chiang Kai-shek and Mao Zedong toasting together in 1945 following the end of World War IIIn the late 1920s, the Kuomintang under Chiang Kai-shek was able to reunify the country under its own control with a series of deft military and political maneuverings known collectively as the Northern Expedition.", "The Kuomintang moved the nation's capital to Nanjing and implemented \"political tutelage\", an intermediate stage of political development outlined in Sun Yat-sen's Three Principles of the People program for transforming China into a modern democratic state.", "The Kuomintang briefly allied with the Chinese Communist Party (CCP) during the Northern Expedition, though the alliance broke down in 1927 after Chiang violently suppressed the CCP and other leftists Shanghai, marking the beginning of the Chinese Civil War.", "The CCP declared areas of the country as the Chinese Soviet Republic (Jiangxi Soviet) in November 1931 in Ruijin, Jiangxi.", "The Jiangxi Soviet was wiped out by the KMT armies in 1934, leading the CCP to initiate the Long March and relocate to Yan'an in Shaanxi.", "It would be the base of the communists before major combat in the Chinese Civil War ended in 1949.In 1931, Japan invaded and occupied Manchuria.", "Japan invaded other parts of China in 1937, precipitating the Second Sino-Japanese War (1937–1945), a theater of World War II.", "The war forced an uneasy alliance between the Kuomintang and the CCP.", "Japanese forces committed numerous war atrocities against the civilian population; as many as 20 million Chinese civilians died.", "An estimated 40,000 to 300,000 Chinese were massacred in Nanjing alone during the Japanese occupation.", "China, along with the UK, the United States, and the Soviet Union, were recognized as the Allied \"Big Four\" in the Declaration by United Nations.", "Along with the other three great powers, China was one of the four major Allies of World War II, and was later considered one of the primary victors in the war.", "After the surrender of Japan in 1945, Taiwan, including the Penghu, was handed over to Chinese control; however, the validity of this handover is controversial.=== People's Republic ===The founding ceremony of the People's Republic of China was held at 3:00 pm on October 1, 1949.The picture above shows Mao Zedong's announcement of the founding of the People's Republic of China in Tiananmen Square.China emerged victorious but war-ravaged and financially drained.", "The continued distrust between the Kuomintang and the Communists led to the resumption of civil war.", "Constitutional rule was established in 1947, but because of the ongoing unrest, many provisions of the ROC constitution were never implemented in mainland China.", "Afterwards, the CCP took control of most of mainland China, and the ROC government retreated offshore to Taiwan.On 1 October 1949, CCP Chairman Mao Zedong formally proclaimed the People's Republic of China in Tiananmen Square, Beijing.", "In 1950, the PRC captured Hainan from the ROC and annexed Tibet.", "However, remaining Kuomintang forces continued to wage an insurgency in western China throughout the 1950s.", "The CCP consolidated its popularity among the peasants through the Land Reform Movement, which included the execution of between 1 and 2 million landlords.", "Though the PRC initially allied closely with the Soviet Union, the relations between the two communist nations gradually deteriorated, leading China to develop an independent industrial system and its own nuclear weapons.The Chinese population increased from 550 million in 1950 to 900 million in 1974.However, the Great Leap Forward, an idealistic massive industrialization project, resulted in an estimated 15 to 55 million deaths between 1959 and 1961, mostly from starvation.", "In 1964, China's first atomic bomb exploded successfully.", "In 1966, Mao and his allies launched the Cultural Revolution, sparking a decade of political recrimination and social upheaval that lasted until Mao's death in 1976.In October 1971, the PRC replaced the ROC in the United Nations, and took its seat as a permanent member of the Security Council.=== Reforms and contemporary history ===The 1989 Tiananmen Square protests was ended by a military-led massacre.After Mao's death, the Gang of Four was quickly arrested by Hua Guofeng and held responsible for the excesses of the Cultural Revolution.", "Deng Xiaoping took power in 1978, and instituted large-scale political and economic reforms, together with the \"Eight Elders\", CCP members who held huge influence during this time.", "The CCP loosened governmental control over citizens' personal lives, and the communes were gradually disbanded in favor of working contracted to households.", "The Cultural Revolution was also rebuked, with millions of its victims being rehabilitated.", "Agricultural collectivization was dismantled and farmlands privatized, while foreign trade became a major new focus, leading to the creation of special economic zones (SEZs).", "Inefficient state-owned enterprises (SOEs) were restructured and unprofitable ones were closed outright, resulting in job losses.", "This marked China's transition from a planned economy to a mixed economy with an increasingly open-market environment.", "China adopted its current constitution on 4 December 1982.In 1989, the country saw large pro-democracy protests, eventually leading to the Tiananmen Square massacre.", "Jiang Zemin was selected to replace the reformist Zhao Ziyang as the CCP general secretary; Zhao was put under house arrest for his sympathies to the protests.", "Jiang continued economic reforms, further closing many SOEs and massively trimming down \"iron rice bowl\" (occupations with guaranteed job security).", "During Jiang's rule, China's economy grew sevenfold.", "British Hong Kong and Portuguese Macau returned to China in 1997 and 1999, respectively, as special administrative regions under the principle of one country, two systems.", "The country joined the World Trade Organization in 2001.Belt and Road Initiative and related projectsBetween 2002 and 2003, Hu Jintao succeeded Jiang as the paramount leader.", "Under Hu, China maintained its high rate of economic growth, overtaking the United Kingdom, France, Germany and Japan to become the world's second-largest economy.", "However, the growth also severely impacted the country's resources and environment, and caused major social displacement.", "Xi Jinping succeeded Hu as paramount leader between 2012 and 2013.Shortly after his ascension to power, Xi launched a vast anti-corruption crackdown, that prosecuted more than 2 million officials by 2022.During his tenure, Xi consolidated power unseen since the initiation of economic and political reforms." ], [ "Geography", "Topographic map of ChinaChina's landscape is vast and diverse, ranging from the Gobi and Taklamakan Deserts in the arid north to the subtropical forests in the wetter south.", "The Himalaya, Karakoram, Pamir and Tian Shan mountain ranges separate China from much of South and Central Asia.", "The Yangtze and Yellow Rivers, the third- and sixth-longest in the world, respectively, run from the Tibetan Plateau to the densely populated eastern seaboard.", "China's coastline along the Pacific Ocean is long and is bounded by the Bohai, Yellow, East China and South China seas.", "China connects through the Kazakh border to the Eurasian Steppe.The territory of China lies between latitudes 18° and 54° N, and longitudes 73° and 135° E. The geographical center of China is marked by the Center of the Country Monument at .", "China's landscapes vary significantly across its vast territory.", "In the east, along the shores of the Yellow Sea and the East China Sea, there are extensive and densely populated alluvial plains, while on the edges of the Inner Mongolian plateau in the north, broad grasslands predominate.", "Southern China is dominated by hills and low mountain ranges, while the central-east hosts the deltas of China's two major rivers, the Yellow River and the Yangtze River.", "Other major rivers include the Xi, Mekong, Brahmaputra and Amur.", "To the west sit major mountain ranges, most notably the Himalayas.", "High plateaus feature among the more arid landscapes of the north, such as the Taklamakan and the Gobi Desert.", "The world's highest point, Mount Everest (8,848 m), lies on the Sino-Nepalese border.", "The country's lowest point, and the world's third-lowest, is the dried lake bed of Ayding Lake (−154 m) in the Turpan Depression.=== Climate ===Köppen-Geiger climate classification map for mainland ChinaChina's climate is mainly dominated by dry seasons and wet monsoons, which lead to pronounced temperature differences between winter and summer.", "In the winter, northern winds coming from high-latitude areas are cold and dry; in summer, southern winds from coastal areas at lower latitudes are warm and moist.A major environmental issue in China is the continued expansion of its deserts, particularly the Gobi Desert.", "Although barrier tree lines planted since the 1970s have reduced the frequency of sandstorms, prolonged drought and poor agricultural practices have resulted in dust storms plaguing northern China each spring, which then spread to other parts of East Asia, including Japan and Korea.", "Water quality, erosion, and pollution control have become important issues in China's relations with other countries.", "Melting glaciers in the Himalayas could potentially lead to water shortages for hundreds of millions of people.", "According to academics, in order to limit climate change in China to electricity generation from coal in China without carbon capture must be phased out by 2045.With current policies, the GHG emissions of China will probably peak in 2025, and by 2030 they will return to 2022 levels.", "However, such pathway still leads to three-degree temperature rise.Official government statistics about Chinese agricultural productivity are considered unreliable, due to exaggeration of production at subsidiary government levels.", "Much of China has a climate very suitable for agriculture and the country has been the world's largest producer of rice, wheat, tomatoes, eggplant, grapes, watermelon, spinach, and many other crops.", "In 2021, 12 percent of global permanent meadows and pastures belonged to China, as well as 8% of global cropland.=== Biodiversity ===A giant panda, China's most famous endangered and endemic species, at the Chengdu Panda Base in SichuanChina is one of 17 megadiverse countries, lying in two of the world's major biogeographic realms: the Palearctic and the Indomalayan.", "By one measure, China has over 34,687 species of animals and vascular plants, making it the third-most biodiverse country in the world, after Brazil and Colombia.", "The country is a party to the Convention on Biological Diversity; its National Biodiversity Strategy and Action Plan was received by the convention in 2010.China is home to at least 551 species of mammals (the third-highest in the world), 1,221 species of birds (eighth), 424 species of reptiles (seventh) and 333 species of amphibians (seventh).", "Wildlife in China shares habitat with, and bears acute pressure from, the world's largest population of humans.", "At least 840 animal species are threatened, vulnerable or in danger of local extinction, due mainly to human activity such as habitat destruction, pollution and poaching for food, fur and traditional Chinese medicine.", "Endangered wildlife is protected by law, and , the country has over 2,349 nature reserves, covering a total area of 149.95 million hectares, 15 percent of China's total land area.", "Most wild animals have been eliminated from the core agricultural regions of east and central China, but they have fared better in the mountainous south and west.", "The Baiji was confirmed extinct on 12 December 2006.China has over 32,000 species of vascular plants, and is home to a variety of forest types.", "Cold coniferous forests predominate in the north of the country, supporting animal species such as moose and Asian black bear, along with over 120 bird species.", "The understory of moist conifer forests may contain thickets of bamboo.", "In higher montane stands of juniper and yew, the bamboo is replaced by rhododendrons.", "Subtropical forests, which are predominate in central and southern China, support a high density of plant species including numerous rare endemics.", "Tropical and seasonal rainforests, though confined to Yunnan and Hainan, contain a quarter of all the animal and plant species found in China.", "China has over 10,000 recorded species of fungi.=== Environment ===The Three Gorges Dam is the largest hydroelectric dam in the world.In the early 2000s, China has suffered from environmental deterioration and pollution due to its rapid pace of industrialization.", "Regulations such as the 1979 Environmental Protection Law are fairly stringent, though they are poorly enforced, frequently disregarded in favor of rapid economic development.", "China has the second highest death toll because of air pollution, after India, with approximately 1 million deaths.", "Although China ranks as the highest CO2 emitting country, it only emits 8 tons of CO2 per capita, significantly lower than developed countries such as the United States (16.1), Australia (16.8) and South Korea (13.6).", "Greenhouse gas emissions by China are the world's largest.", "The country has significant water pollution problems; only 87.9% of China's national surface water was graded suitable for human consumption by the Ministry of Ecology and Environment in 2022.China has prioritized clamping down on pollution, bringing a significant decrease in air pollution in the 2010s.", "In 2020, the Chinese government announced that China aims to peak emissions before 2030 and go carbon-neutral by 2060 in accordance with the Paris Agreement, which, according to Climate Action Tracker, would lower the expected rise in global temperature by 0.2–0.3 degrees – \"the biggest single reduction ever estimated by the Climate Action Tracker\".China is the world's leading investor in renewable energy and its commercialization, with $546 billion invested in 2022; it is a major manufacturer of renewable energy technologies and invests heavily in local-scale renewable energy projects.", "Long heavily relying on non-renewable energy sources such as coal, China's adaptation of renewable energy has increased significantly in recent years, with their share increasing from 26.3 percent in 2016 to 31.9 percent in 2022.In 2022, 61.2% of China's electricity came from coal (largest producer in the world), 14.9% from hydroelectric power (largest), 9.3% from wind (largest), 4.7% from solar energy (largest), 4.7% from nuclear energy (second-largest), 3.1% from natural gas (fifth-largest), and 1.9% from bioenergy (largest); in total, 30.8% of China's energy came from renewable energy sources.", "Despite its emphasis on renewables, China remains deeply connected to global oil markets and next to India, has been the largest importer of Russian crude oil in 2022.=== Political geography ===China is the third-largest country in the world by land area after Russia, and the third or fourth largest country in the world by total area.", "China's total area is generally stated as being approximately .", "Specific area figures range from according to the ''Encyclopædia Britannica'', to according to the ''UN Demographic Yearbook'', and ''The World Factbook''.here.China has the longest combined land border in the world, measuring and its coastline covers approximately from the mouth of the Yalu River (Amnok River) to the Gulf of Tonkin.", "China borders 14 nations and covers the bulk of East Asia, bordering Vietnam, Laos, and Myanmar in Southeast Asia; India, Bhutan, Nepal, Pakistan and Afghanistan in South Asia; Tajikistan, Kyrgyzstan and Kazakhstan in Central Asia; and Russia, Mongolia, and North Korea in Inner Asia and Northeast Asia.", "It is narrowly separated from Bangladesh and Thailand to the southwest and south, and has several maritime neighbors such as Japan, Philippines, Malaysia, and Indonesia.China has resolved its land borders with 12 out of 14 neighboring countries, having pursued substantial compromises in most of them.", "China currently has a disputed land border with India and Bhutan.", "China is additionally involved in maritime disputes with multiple countries over the ownership of islands in the East and South China Seas, such as the Senkaku Islands and the entirety of South China Sea Islands, along with the EEZ disputes over East China Sea." ], [ "Politics", "The People's Republic of China is a one-party state governed by the Marxist–Leninist Chinese Communist Party (CCP).", "This makes China one of the few countries governed by a communist party.", "The Chinese constitution states that the PRC \"is a socialist state governed by a people's democratic dictatorship that is led by the working class and based on an alliance of workers and peasants,\" that the state institutions \"shall practice the principle of democratic centralism,\" and that \"the defining feature of socialism with Chinese characteristics is the leadership of the Communist Party of China.", "\"The PRC officially terms itself as a democracy, using terms such as \"socialist consultative democracy\", and \"whole-process people's democracy\".", "However, the country is commonly described as an authoritarian one-party state and a dictatorship, with among the heaviest restrictions worldwide in many areas, most notably against freedom of the press, freedom of assembly, reproductive rights, free formation of social organizations, freedom of religion and free access to the Internet.", "China has consistently been ranked amongst the lowest as an \"authoritarian regime\" by the Economist Intelligence Unit's Democracy Index, ranking at 148th out of 167 countries in 2023.=== Chinese Communist Party ===The Chinese Communist Party is the founding and ruling political party of the People's Republic of China.According to the CCP constitution, its highest body is the National Congress held every five years.", "The National Congress elects the Central Committee, who then elects the party's Politburo, Politburo Standing Committee and the general secretary (party leader), the top leadership of the country.", "The general secretary holds ultimate power and authority over state and government and serves as the informal paramount leader.", "The current general secretary is Xi Jinping, who took office on 15 November 2012.At the local level, the secretary of the CCP committee of a subdivision outranks the local government level; CCP committee secretary of a provincial division outranks the governor while the CCP committee secretary of a city outranks the mayor.", "The CCP is officially guided by Marxism adapted to Chinese circumstances.=== Government ===The government in China is under the sole control of the CCP.", "The CCP controls appointments in government bodies, with most senior government officials being CCP members.The National People's Congress (NPC), the nearly 3,000-member legislature, is constitutionally the \"highest organ of state power\", though it has been also described as a \"rubber stamp\" body.", "The NPC meets annually, while the NPC Standing Committee, around 150 members elected from NPC delegates, meets every couple of months.", "Elections are indirect and not pluralistic, with nominations at all levels being controlled by the CCP.", "The NPC is dominated by the CCP, with another eight minor parties having nominal representation under the condition of upholding CCP leadership.The president is the ceremonial state representative, elected by the NPC.", "The incumbent president is Xi Jinping, who is also the general secretary of the CCP and the chairman of the Central Military Commission, making him China's paramount leader.", "The premier is the head of government, with Li Qiang being the incumbent.", "The premier is officially nominated by the president and then elected by the NPC, and has generally been either the second or third-ranking member of the Politburo Standing Committee (PSC).", "The premier presides over the State Council, China's cabinet, composed of four vice premiers, state councilors, and the heads of ministries and commissions.", "The Chinese People's Political Consultative Conference (CPPCC) is a political advisory body that is critical in China's \"united front\" system, which aims to gather non-CCP voices to support the CCP.", "Similar to the people's congresses, CPPCC's exist at various division, with the National Committee of the CPPCC being chaired by Wang Huning, fourth-ranking member of the PSC.The governance of China is characterized by a high degree of political centralization but significant economic decentralization.", "Policy instruments or processes are often tested locally before being applied more widely, resulting in a policy process that involves experimentation and feedback.", "Generally, high-level central government leadership refrains from drafting specific policies, instead using the informal networks and site visits to affirm or suggest changes to the direction of local policy experiments or pilot programs.", "The typical approach is that central government leadership begins drafting formal policies, law, or regulations after policy has been developed at local levels.=== Administrative divisions ===The PRC is constitutionally a unitary state divided into 23 provinces, five autonomous regions (each with a designated minority group), and four direct-administered municipalities—collectively referred to as \"mainland China\"—as well as the special administrative regions (SARs) of Hong Kong and Macau.", "The PRC regards the island of Taiwan as its Taiwan Province, Kinmen and Matsu as a part of Fujian Province and islands the ROC controls in the South China Sea as a part of Hainan Province and Guangdong Province, although all these territories are governed by the Republic of China (ROC).", "Geographically, all 31 provincial divisions of mainland China can be grouped into six regions: North China, Northeast China, East China, South Central China, Southwestern China, and Northwestern China.=== Foreign relations ===Diplomatic relations of ChinaThe PRC has diplomatic relations with 179 United Nation members states and maintains embassies in 174.In 2021, China has the largest diplomatic network of any country in the world.", "In 1971, the PRC replaced the Republic of China (ROC) as the sole representative of China in the United Nations and as one of the five permanent members of the United Nations Security Council.", "It is a member of intergovernmental organizations including the G20, the SCO, the East Asia Summit, and the APEC.", "China was also a former member and leader of the Non-Aligned Movement, and still considers itself an advocate for developing countries.", "Along with Brazil, Russia, India and South Africa, China is a member of the BRICS group of emerging major economies and hosted the group's third official summit in April 2011.The PRC officially maintains the one-China principle, which holds the view that there is only one sovereign state in the name of China, represented by the PRC, and that Taiwan is part of that China.", "The unique status of Taiwan has led to countries recognizing the PRC to maintain unique \"one-China policies\" that differ from each other; some countries explicitly recognize the PRC's claim over Taiwan, while others, including the US and Japan, only ''acknowledge'' the claim.", "Chinese officials have protested on numerous occasions when foreign countries have made diplomatic overtures to Taiwan, especially in the matter of armament sales.", "Most countries have switched recognition from the ROC to the PRC since the latter replaced the former in the UN in 1971.On 21 May 2014, China and Russia signed a $400 billion gas deal.", "Currently, Russia is supplying natural gas to China.Much of current Chinese foreign policy is reportedly based on Premier Zhou Enlai's Five Principles of Peaceful Coexistence, and is also driven by the concept of \"harmony without uniformity\", which encourages diplomatic relations between states despite ideological differences.", "This policy may have led China to support or maintain close ties with states that are regarded as dangerous and repressive by Western nations, such as Sudan, North Korea and Iran.", "China's close relationship with Myanmar has involved support for its ruling governments as well as for its ethnic rebel groups, including the Arakan Army.", "China has a close political, economic and military relationship with Russia, and the two states often vote in unison in the UN Security Council.", "China's relationship with the United States is complex, and includes deep trade ties but significant political differences.Since the early 2000s, China has followed a policy of engaging with African nations for trade and bilateral co-operation.", "It maintains extensive and highly diversified trade links with the European Union, and became its largest trading partner for goods.", "China has strong trade ties with ASEAN countries and major South American economies, and is the largest trading partner of Brazil, Chile, Peru, Uruguay, Argentina, and several others.In 2013, China initiated the Belt and Road Initiative (BRI), a large global infrastructure building initiative with funding on the order of $50–100 billion per year.", "BRI could be one of the largest development plans in modern history.", "It has expanded significantly over the last six years and, , includes 138 countries and 30 international organizations.", "In addition to intensifying foreign policy relations, the focus is particularly on building efficient transport routes, especially the maritime Silk Road with its connections to East Africa and Europe.", "However many loans made under the program are unsustainable and China has faced a number of calls for debt relief from debtor nations.=== Sociopolitical issues and human rights ===Nobel Peace Prize laureate Liu Xiaobo who died of organ failure while in government custody in 2017The situation of human rights in China has attracted significant criticism from foreign governments, foreign press agencies, and non-governmental organizations, alleging widespread civil rights violations such as detention without trial, forced confessions, torture, restrictions of fundamental rights, and excessive use of the death penalty.", "Since its inception, Freedom House has ranked China as \"not free\" in its ''Freedom in the World'' survey, while Amnesty International has documented significant human rights abuses.", "The Chinese constitution states that the \"fundamental rights\" of citizens include freedom of speech, freedom of the press, the right to a fair trial, freedom of religion, universal suffrage, and property rights.", "However, in practice, these provisions do not afford significant protection against criminal prosecution by the state.", "China has limited protections regarding LGBT rights.Although some criticisms of government policies and the ruling CCP are tolerated, censorship of political speech and information are amongst the harshest in the world and routinely used to prevent collective action.", "China also has the most comprehensive and sophisticated Internet censorship regime in the world, with numerous websites being blocked.", "The government suppresses popular protests and demonstrations that it considers a potential threat to \"social stability\".", "China additionally uses a massive espionage network of cameras, facial recognition software, sensors, and surveillance of personal technology as a means of social control of persons living in the country.In Xinjiang, China has been accused of committing genocide against Uyghurs and detaining more than one million Uyghurs and other ethnic minorities in camps.China is regularly accused of large-scale repression and human rights abuses in Tibet and Xinjiang, where significant numbers of ethnic minorities reside, including violent police crackdowns and religious suppression.", "Since 2017, the Chinese government has been engaged in a harsh crackdown in Xinjiang, with around one million Uyghurs and other ethnic and religion minorities being detained in internment camps aimed at changing the political thinking of detainees, their identities, and their religious beliefs.", "According to Western reports, political indoctrination, torture, physical and psychological abuse, forced sterilization, sexual abuse, and forced labor are common in these facilities.", "According to a 2020 report, China's treatment of Uyghurs meets the UN definition of genocide, while a separate UN Human Rights Office report said they could potentially meet the definitions for crimes against humanity.", "The Chinese authorities have also cracked down on dissent in Hong Kong, especially after the passage of a national security law in 2020.2019–20 Hong Kong protestsIn 2017 and 2020, the Pew Research Center ranked the severity of Chinese government restrictions on religion as being among the world's highest, despite ranking religious-related social hostilities in China as low in severity.", "The Global Slavery Index estimated that in 2016 more than 3.8 million people (0.25% of the population) were living in \"conditions of modern slavery\", including victims of human trafficking, forced labor, forced marriage, child labor, and state-imposed forced labor.", "The state-imposed re-education through labor (''laojiao'') system was formally abolished in 2013, but it is not clear to what extent its practices have stopped.", "The much larger reform through labor (''laogai'') system includes labor prison factories, detention centers, and re-education camps; the Laogai Research Foundation has estimated in June 2008 that there were nearly 1,422 of these facilities, though it cautioned that this number was likely an underestimate.=== Public views of government ===Political concerns in China include the growing gap between rich and poor and government corruption.", "Nonetheless, international surveys show the Chinese public have a high level of satisfaction with their government.", "These views are generally attributed to the material comforts and security available to large segments of the Chinese populace as well as the government's attentiveness and responsiveness.", "According to the World Values Survey (2022), 91% of Chinese respondents have significant confidence in their government.", "A Harvard University survey published in July 2020 found that citizen satisfaction with the government had increased since 2003, also rating China's government as more effective and capable than ever in the survey's history." ], [ "Military", "Chengdu J-20 5th generation stealth fighterThe People's Liberation Army (PLA) is considered one of the world's most powerful militaries and has rapidly modernized in the recent decades however, it has also been accused of technology theft by some countries.", "It consists of the Ground Force (PLAGF), the Navy (PLAN), the Air Force (PLAAF), the Rocket Force (PLARF) and the Strategic Support Force (PLASSF).", "Its nearly 2.2 million active duty personnel is the largest in the world.", "The PLA holds the world's third-largest stockpile of nuclear weapons, and the world's second-largest navy by tonnage.", "China's official military budget for 2022 totalled US$230 billion (1.45 trillion Yuan), the second-largest in the world, though SIPRI estimates that its real expenditure that year was US$292 billion.", "According to SIPRI, its military spending from 2012 to 2021 averaged US$215 billion per year or 1.7 per cent of GDP, behind only the United States at US$734 billion per year or 3.6 per cent of GDP.", "The PLA is commanded by the Central Military Commission (CMC) of the party and the state; though officially two separate organizations, the two CMCs have identical membership except during leadership transition periods and effectively function as one organization.", "The chairman of the CMC is the commander-in-chief of the PLA." ], [ "Economy", "China has the world's second-largest economy in terms of nominal GDP, and the world's largest in terms of purchasing power parity (PPP).", ", China accounts for around 18% of global economy by nominal GDP.", "China is one of the world's fastest-growing major economies, with its economic growth having been almost consistently above 6 percent since the introduction of economic reforms in 1978.According to the World Bank, China's GDP grew from $150 billion in 1978 to $17.96 trillion by 2022.It ranks at 64th at GDP (nominal) per capita, making it an upper-middle income country.", "Of the world's 500 largest companies, 142 are headquartered in China.China was one of the world's foremost economic powers throughout the arc of East Asian and global history.", "The country had one of the largest economies in the world for most of the past two millennia, during which it has seen cycles of prosperity and decline.", "Since economic reforms began in 1978, China has developed into a highly diversified economy and one of the most consequential players in international trade.", "Major sectors of competitive strength include manufacturing, retail, mining, steel, textiles, automobiles, energy generation, green energy, banking, electronics, telecommunications, real estate, e-commerce, and tourism.", "China has three out of the ten largest stock exchanges in the world—Shanghai, Hong Kong and Shenzhen—that together have a market capitalization of over $15.9 trillion, .", "China has four (Shanghai, Hong Kong, Beijing, and Shenzhen) out of the world's top ten most competitive financial centers, which is more than any other country in the 2020 Global Financial Centres Index.GDP per capita at purchasing-power parity, 1990–2013.The rapid economic growth of China (blue) is readily apparent.Modern-day China is often described as an example of state capitalism or party-state capitalism.", "The state dominates in strategic \"pillar\" sectors such as energy production and heavy industries, but private enterprise has expanded enormously, with around 30 million private businesses recorded in 2008.According to official statistics, privately owned companies constitute more than 60% of China's GDP.China has been the world's largest manufacturing nation since 2010, after overtaking the US, which had been the largest for the previous hundred years.", "China has also been the second largest in high-tech manufacturing country since 2012, according to US National Science Foundation.", "China is the second largest retail market after the United States.", "China leads the world in e-commerce, accounting for over 37% of the global market share in 2021.China is the world's leader in electric vehicle consumption and production, manufacturing and buying half of all the plug-in electric cars (BEV and PHEV) in the world .", "China is also the leading producer of batteries for electric vehicles as well as several key raw materials for batteries.=== Wealth ===Shanghai World Financial Center, Jin Mao Tower and Shanghai Tower, LujiazuiChina accounted for 17.9% of the world's total wealth in 2021, second highest in the world after the US.", "China brought more people out of extreme poverty than any other country in history—between 1978 and 2018, China reduced extreme poverty by 800 million.", "From 1990 to 2018, the proportion of the Chinese population living with an income of less than $1.90 per day (2011 PPP) decreased from 66.3% to 0.3%, the share living with an income of less than $3.20 per day from 90.0% to 2.9%, and the share living with an income of less than $5.50 per day decreased from 98.3% to 17.0%.From 1978 to 2018, the average standard of living multiplied by a factor of twenty-six.", "Wages in China have grown significantly in the last 40 years—real (inflation-adjusted) wages grew seven-fold from 1978 to 2007.Per capita incomes have also risen significantly – when the PRC was founded in 1949, per capita income in China was one-fifth of the world average; per capita incomes now equal the world average itself.", "China's development is highly uneven.", "Its major cities and coastal areas are far more prosperous compared to rural and interior regions.", "It has a high level of economic inequality, which has increased quickly after the economic reforms, though has decreased significantly in the 2010s.", "In 2020, China's Gini coefficient was 0.371, according to the World Bank., China was second in the world, after the US, in total number of billionaires and total number of millionaires, with 495 Chinese billionaires and 6.2 million millionaires.", "In 2019, China overtook the US as the home to the highest number of people who have a net personal wealth of at least $110,000, according to the global wealth report by Credit Suisse.", "China had 85 female billionaires , two-thirds of the global total.", "China has had the world's largest middle-class population since 2015; the middle-class grew to 400 million by 2018.=== China in the global economy ===ImageSize = width:auto height:250 barincrement:50PlotArea = left:70 bottom:15 top:10 right:0AlignBars = justifyTimeAxis = orientation:verticalDateFormat = x.yPeriod = from:0.0 till:30ScaleMajor = unit:day start:0.0 increment:2PlotData = color:blue width:25 bar:US from:start till:26.854 bar:China from:start till:19.791 bar:Japan from:start till:4.409 bar:Germany from:start till:4.308 bar:India from:start till:3.736TextData = pos:(0,125) text:US$ TnLargest economies by nominal GDP in 2023China has been a member of the WTO since 2001 and is the world's largest trading power.", "By 2016, China was the largest trading partner of 124 countries.", "China became the world's largest trading nation in 2013 by the sum of imports and exports, as well as the world's largest commodity importer, comprising roughly 45% of maritime's dry-bulk market.China's foreign exchange reserves reached US$3.128 trillion , making its reserves by far the world's largest.", "In 2022, China was amongst the world's largest recipient of inward foreign direct investment (FDI), attracting $180 billion, though most of these were speculated to be from Hong Kong.", "In 2021, China's foreign exchange remittances were $US53 billion making it the second largest recipient of remittances in the world.", "China also invests abroad, with a total outward FDI of $146.5 billion in 2022, and a number of major takeovers of foreign firms by Chinese companies.Economists have argued that the renminbi is undervalued, due to currency intervention from the Chinese government, giving China an unfair trade advantage.", "China has also been widely criticized for manufacturing large quantities of counterfeit goods.", "The US government has also alleged that China does not respect intellectual property (IP) rights and steals IP through espionage operations.", "In 2020, Harvard University's Economic Complexity Index ranked complexity of China's exports 17th in the world, up from 24th in 2010.The Chinese government has promoted the internationalization of the renminbi in order to wean off of its dependence on the U.S. dollar as a result of perceived weaknesses of the international monetary system.", "The renminbi is a component of the IMF's special drawing rights and the world's fifth-most traded currency .", "However, partly due to capital controls that make the renminbi fall short of being a fully convertible currency, it remains far behind the Euro, the U.S. Dollar and the Japanese Yen in international trade volumes." ], [ "Science and technology", "=== Historical ===Earliest known written formula for gunpowder, from the ''Wujing Zongyao'' of 1044 CEChina was a world leader in science and technology until the Ming dynasty.", "Ancient and medieval Chinese discoveries and inventions, such as papermaking, printing, the compass, and gunpowder (the Four Great Inventions), became widespread across East Asia, the Middle East and later Europe.", "Chinese mathematicians were the first to use negative numbers.", "By the 17th century, the Western World surpassed China in scientific and technological advancement.", "The causes of this early modern Great Divergence continue to be debated by scholars.After repeated military defeats by the European colonial powers and Imperial Japan in the 19th century, Chinese reformers began promoting modern science and technology as part of the Self-Strengthening Movement.", "After the Communists came to power in 1949, efforts were made to organize science and technology based on the model of the Soviet Union, in which scientific research was part of central planning.", "After Mao's death in 1976, science and technology were promoted as one of the Four Modernizations, and the Soviet-inspired academic system was gradually reformed.=== Modern era ===Since the end of the Cultural Revolution, China has made significant investments in scientific research and is quickly catching up with the US in R&D spending.", "China officially spent around 2.4% of its GDP on R&D in 2020, totaling to around $377.8 billion.", "According to the World Intellectual Property Indicators, China received more applications than the US did in 2018 and 2019 and ranked first globally in patents, utility models, trademarks, industrial designs, and creative goods exports in 2021.It was ranked 12th in the Global Innovation Index in 2023, a considerable improvement from its rank of 35th in 2013.Chinese supercomputers have been ranked the fastest in the world on a few occasions; however, these supercomputers rely on critical components —namely processors—designed in foreign countries.", "China has also struggled with developing several technologies domestically, such as the most advanced semiconductors and reliable jet engines.China is developing its education system with an emphasis on science, technology, engineering, and mathematics (STEM).", "It became the world's largest publisher of scientific papers in 2016.==== Space program ====Launch of Shenzhou 13 by a Long March 2F rocket.", "China is one of the only three countries with independent human spaceflight capability.The Chinese space program started in 1958 with some technology transfers from the Soviet Union.", "However, it did not launch the nation's first satellite until 1970 with the Dong Fang Hong I, which made China the fifth country to do so independently.In 2003, China became the third country in the world to independently send humans into space with Yang Liwei's spaceflight aboard Shenzhou 5.As of 2023, eighteen Chinese nationals have journeyed into space, including two women.", "In 2011, China launched its first space station testbed, Tiangong-1.In 2013, a Chinese robotic rover Yutu successfully touched down on the lunar surface as part of the Chang'e 3 mission.In 2019, China became the first country to land a probe—Chang'e 4—on the far side of the Moon.", "In 2020, Chang'e 5 successfully returned Moon samples to the Earth, making China the third country to do so independently.", "In 2021, China became the third country to land a spacecraft on Mars and the second one to deploy a rover (Zhurong) on Mars.", "China completed its own modular space station, the ''Tiangong'', in low Earth orbit on 3 November 2022.On 29 November 2022, China performed its first in-orbit crew handover aboard the ''Tiangong''.In May 2023, China announced a plan to land humans on the Moon by 2030.To that end, China currently is developing a lunar-capable super-heavy launcher, the Long March 10, a new crewed spacecraft, and a crewed lunar lander." ], [ "Infrastructure", "After a decades-long infrastructural boom, China has produced numerous world-leading infrastructural projects: it has the largest high-speed rail network, the most supertall skyscrapers, the largest power plant (the Three Gorges Dam), and a global satellite navigation system with the largest number of satellites.=== Telecommunications ===Internet penetration rates in China in the context of East Asia and Southeast Asia, 1995–2012China is the largest telecom market in the world and currently has the largest number of active cellphones of any country, with over 1.7 billion subscribers, .", "It has the largest number of internet and broadband users, with over 1.05 billion Internet users —equivalent to around 73.7% of its population.", "By 2018, China had more than 1 billion 4G users, accounting for 40% of world's total.", "China is making rapid advances in 5G—by late 2018, China had started large-scale and commercial 5G trials.", ", China had over 500 million 5G users and 1.45 million base stations installed.China Mobile, China Unicom and China Telecom, are the three large providers of mobile and internet in China.", "China Telecom alone served more than 145 million broadband subscribers and 300 million mobile users; China Unicom had about 300 million subscribers; and China Mobile, the largest of them all, had 925 million users, .", "Combined, the three operators had over 3.4 million 4G base-stations in China.", "Several Chinese telecommunications companies, most notably Huawei and ZTE, have been accused of spying for the Chinese military.China has developed its own satellite navigation system, dubbed BeiDou, which began offering commercial navigation services across Asia in 2012 as well as global services by the end of 2018.Beidou followed GPS and GLONASS as the third completed global navigation satellite.=== Transport ===Since the late 1990s, China's national road network has been significantly expanded through the creation of a network of national highways and expressways.", "In 2018, China's highways had reached a total length of , making it the longest highway system in the world.", "China has the world's largest market for automobiles, having surpassed the United States in both auto sales and production.", "The country is the world's largest exporter of cars as of 2023.A side-effect of the rapid growth of China's road network has been a significant rise in traffic accidents.", "In urban areas, bicycles remain a common mode of transport, despite the increasing prevalence of automobiles – , there are approximately 470 million bicycles in China.China's railways, which are operated by the state-owned China State Railway Group Company, are among the busiest in the world, handling a quarter of the world's rail traffic volume on only 6 percent of the world's tracks in 2006., the country had of railways, the second longest network in the world.", "The railways strain to meet enormous demand particularly during the Chinese New Year holiday, when the world's largest annual human migration takes place.", "China's high-speed rail (HSR) system started construction in the early 2000s.", "By the end of 2022, high speed rail in China had reached of dedicated lines alone, making it the longest HSR network in the world.", "Services on the Beijing–Shanghai, Beijing–Tianjin, and Chengdu–Chongqing lines reach up to , making them the fastest conventional high speed railway services in the world.", "With an annual ridership of over 2.3 billion passengers in 2019, it is the world's busiest.", "The network includes the Beijing–Guangzhou high-speed railway, the single longest HSR line in the world, and the Beijing–Shanghai high-speed railway, which has three of longest railroad bridges in the world.", "The Shanghai maglev train, which reaches , is the fastest commercial train service in the world.", "Since 2000, the growth of rapid transit systems in Chinese cities has accelerated.", ", 44 Chinese cities have urban mass transit systems in operation.", ", China boasts the five longest metro systems in the world with the networks in Shanghai, Beijing, Guangzhou, Chengdu and Shenzhen being the largest.The civil aviation industry in China is mostly state-dominated, with the Chinese government retaining a majority stake in the majority of Chinese airlines.", "The top three airlines in China, which collectively made up 71% of the market in 2018, are all state-owned.", "Air travel has expanded rapidly in the last decades, with the number of passengers increasing from 16.6 million in 1990 to 551.2 million in 2017.China had approximately 241 airports in 2021.China has over 2,000 river and seaports, about 130 of which are open to foreign shipping.", "Of the fifty busiest container ports, 15 are located in China, of which the busiest is the Port of Shanghai, also the busiest port in the world.", "The country's inland waterways are the world's sixth-longest, and total .=== Water supply and sanitation ===Water supply and sanitation infrastructure in China is facing challenges such as rapid urbanization, as well as water scarcity, contamination, and pollution.", "According to the Joint Monitoring Program for Water Supply and Sanitation in 2015, about 36% of the rural population in China still did not have access to improved sanitation.", "The ongoing South–North Water Transfer Project intends to abate water shortage in the north." ], [ "Demographics", "Population density map of the People's Republic of China (2000)The 2020 Chinese census recorded the population as approximately 1,411,778,724.About 17.95% were 14 years old or younger, 63.35% were between 15 and 59 years old, and 18.7% were over 60 years old.", "Between 2010 and 2020, the average population growth rate was 0.53%.Given concerns about population growth, China implemented a two-child limit during the 1970s, and, in 1979, began to advocate for an even stricter limit of one child per family.", "Beginning in the mid-1980s, however, given the unpopularity of the strict limits, China began to allow some major exemptions, particularly in rural areas, resulting in what was actually a \"1.5\"-child policy from the mid-1980s to 2015; ethnic minorities were also exempt from one-child limits.", "The next major loosening of the policy was enacted in December 2013, allowing families to have two children if one parent is an only child.", "In 2016, the one-child policy was replaced in favor of a two-child policy.", "A three-child policy was announced on 31 May 2021, due to population aging, and in July 2021, all family size limits as well as penalties for exceeding them were removed.", "In 2023, the total fertility rate was reported to be 1.09, ranking among the lowest in the world.", "In 2023, National Bureau of Statistics estimated that the population fell 850,000 from 2021 to 2022, the first decline since 1961.According to one group of scholars, one-child limits had little effect on population growth or total population size.", "However, these scholars have been challenged.", "The policy, along with traditional preference for boys, may have contributed to an imbalance in the sex ratio at birth.", "The 2020 census found that males accounted for 51.2% of the total population.", "However, China's sex ratio is more balanced than it was in 1953, when males accounted for 51.8% of the population.=== Ethnic groups ===Ethnolinguistic map of China in 1967China legally recognizes 56 distinct ethnic groups, who comprise the ''Zhonghua minzu''.", "The largest of these nationalities are the Han Chinese, who constitute more than 91% of the total population.", "The Han Chinese – the world's largest single ethnic group – outnumber other ethnic groups in every provincial-level division except Tibet and Xinjiang.", "Ethnic minorities account for less than 10% of the population of China, according to the 2020 census.", "Compared with the 2010 population census, the Han population increased by 60,378,693 persons, or 4.93%, while the population of the 55 national minorities combined increased by 11,675,179 persons, or 10.26%.", "The 2020 census recorded a total of 845,697 foreign nationals living in mainland China.=== Languages ===Lihaozhai High School in Jianshui, Yunnan.", "The sign is in Hani (Latin alphabet), Nisu (Yi script), and Chinese.There are as many as 292 living languages in China.", "The languages most commonly spoken belong to the Sinitic branch of the Sino-Tibetan language family, which contains Mandarin (spoken by 80% of the population), and other varieties of Chinese language: Jin, Wu, Min, Hakka, Yue, Xiang, Gan, Hui, Ping and unclassified Tuhua (Shaozhou Tuhua and Xiangnan Tuhua).", "Languages of the Tibeto-Burman branch, including Tibetan, Qiang, Naxi and Yi, are spoken across the Tibetan and Yunnan–Guizhou Plateau.", "Other ethnic minority languages in southwestern China include Zhuang, Thai, Dong and Sui of the Tai-Kadai family, Miao and Yao of the Hmong–Mien family, and Wa of the Austroasiatic family.", "Across northeastern and northwestern China, local ethnic groups speak Altaic languages including Manchu, Mongolian and several Turkic languages: Uyghur, Kazakh, Kyrgyz, Salar and Western Yugur.", "Korean is spoken natively along the border with North Korea.", "Sarikoli, the language of Tajiks in western Xinjiang, is an Indo-European language.", "Taiwanese indigenous peoples, including a small population on the mainland, speak Austronesian languages.Standard Mandarin, a variety of Mandarin based on the Beijing dialect, is the national language and ''de facto'' official language of China.", "It is used as a lingua franca between people of different linguistic backgrounds.", "In the autonomous regions of China, other languages may also serve as a lingua franca, such as Uyghur in Xinjiang, where governmental services in Uyghur are constitutionally guaranteed.=== Urbanization ===largest cities in China (2010)China has urbanized significantly in recent decades.", "The percent of the country's population living in urban areas increased from 20% in 1980 to over 64% in 2021.China has over 160 cities with a population of over one million, including the 17 megacities (cities with a population of over 10 million) of Chongqing, Shanghai, Beijing, Chengdu, Guangzhou, Shenzhen, Tianjin, Xi'an, Suzhou, Zhengzhou, Wuhan, Hangzhou, Linyi, Shijiazhuang, Dongguan, Qingdao and Changsha.", "The total permanent population of Chongqing, Shanghai, Beijing and Chengdu is above 20 million.", "Shanghai is China's most populous urban area while Chongqing is its largest city proper, the only city in China with a permanent population of over 30 million.", "The figures in the table below are from the 2020 census, and are only estimates of the urban populations within administrative city limits; a different ranking exists for total municipal populations.", "The large \"floating populations\" of migrant workers make conducting censuses in urban areas difficult; the figures below include only long-term residents.=== Education ===Beijing's Peking University, one of the top-ranked universities in ChinaCompulsory education in China comprises primary and junior secondary school, which together last for nine years from the age of 6 and 15.The Gaokao, China's national university entrance exam, is a prerequisite for entrance into most higher education institutions.", "Vocational education is available to students at the secondary and tertiary level.", "More than 10 million Chinese students graduated from vocational colleges every year.", "In 2022, about 91.6 percent of students continued their education at a three-year senior secondary school, while 59.6 secondary school graduates were enrolled in higher education.China has the largest education system in the world, with about 282 million students and 17.32 million full-time teachers in over 530,000 schools.", "Annual education investment went from less than US$50 billion in 2003 to more than US$817 billion in 2020.However, there remains an inequality in education spending.", "In 2010, the annual education expenditure per secondary school student in Beijing totalled ¥20,023, while in Guizhou, one of the poorest provinces, only totalled ¥3,204.China's literacy rate has grown dramatically, from only 20% in 1949 and 65.5% in 1979, to 97% of the population over age 15 in 2020., China has over 3,000 universities, with over 44.3 million students enrolled in mainland China and 240 million Chinese citizens have received high education, making China the largest higher education system in the world.", ", China had the world's highest number of top universities.", "Currently, China trails only the United States and the United Kingdom in terms of representation on lists of the top 200 universities according to the 2023 ''Aggregate Ranking of Top Universities'', a composite ranking system of three world-most followed university rankings (ARWU+QS+ THE).", "China is home to two of the highest-ranking universities (Tsinghua University and Peking University) in Asia and emerging economies, according to the Times Higher Education World University Rankings and the QS World University Rankings.", "These universities are members of the C9 League, an alliance of elite Chinese universities offering comprehensive and leading education.=== Health ===Chart showing the rise of China's Human Development Index from 1970 to 2010The National Health Commission, together with its counterparts in the local commissions, oversees the health needs of the population.", "An emphasis on public health and preventive medicine has characterized Chinese health policy since the early 1950s.", "The Communist Party started the Patriotic Health Campaign, which was aimed at improving sanitation and hygiene, as well as treating and preventing several diseases.", "Diseases such as cholera, typhoid and scarlet fever, which were previously rife in China, were nearly eradicated by the campaign.After Deng Xiaoping began instituting economic reforms in 1978, the health of the Chinese public improved rapidly because of better nutrition, although many of the free public health services provided in the countryside disappeared.", "Healthcare in China became mostly privatized, and experienced a significant rise in quality.", "In 2009, the government began a three-year large-scale healthcare provision initiative worth US$124 billion.", "By 2011, the campaign resulted in 95% of China's population having basic health insurance coverage.", "By 2022, China had established itself as a key producer and exporter of pharmaceuticals, producing around 40 percent of active pharmaceutical ingredients in 2017., the life expectancy at birth exceeds 78 years.", "As of 2021, the infant mortality rate is 5 per thousand.", "Both have improved significantly since the 1950s.", "Rates of stunting, a condition caused by malnutrition, have declined from 33.1% in 1990 to 9.9% in 2010.Despite significant improvements in health and the construction of advanced medical facilities, China has several emerging public health problems, such as respiratory illnesses caused by widespread air pollution, hundreds of millions of cigarette smokers, and an increase in obesity among urban youths.", "In 2010, air pollution caused 1.2 million premature deaths in China.", "Chinese mental health services are inadequate, and more than 95 million people suffering from depression in the country.", "China's large population and densely populated cities have led to serious disease outbreaks, such as SARS in 2003, although this has since been largely contained.", "The COVID-19 pandemic was first identified in Wuhan in December 2019; pandemic led the government to enforce strict public health measures intended to completely eradicate the virus, a goal that was eventually abandoned in December 2022 after protests against the policy.===Religion===File:Distribution of religions in China.png|thumb|upright=1.35|Geographic distribution of religions in China: Chinese folk religion (including Confucianism, Taoism, and groups of Chinese Buddhism) Buddhism ''tout court'' Islam Ethnic minorities' indigenous religions Mongolian folk religion Northeast China folk religion influenced by Tungus and Manchu shamanism; widespread ShanrendaoFreedom of religion is guaranteed by China's constitution (Chapter 2, Article 36), although religious organizations that lack official approval can be subject to state persecution.", "The government of the country is officially atheist.", "Religious affairs and issues in the country are overseen by the National Religious Affairs Administration, under the United Front Work Department.Over the millennia, the Chinese civilization has been influenced by various religious movements.", "The \"three doctrines\", including Confucianism, Taoism, and Buddhism (Chinese Buddhism), historically have a significant role in shaping Chinese culture, enriching a theological and spiritual framework of traditional religion which harks back to the early Shang and Zhou dynasty.", "Chinese folk religion, which is framed by the three doctrines and by other traditions, consists in allegiance to the ''shen'' (神), a character that signifies the \"energies of generation\", who can be deities of the surrounding nature or ancestral principles of human groups, concepts of civility, culture heroes, many of whom feature in Chinese mythology and history.", "Amongst the most popular cults of folk religion are those of Huangdi, embodiment of the God of Heaven and one of the two divine patriarchs of the Chinese people, of Mazu (goddess of the seas), Guandi (god of war and business), Caishen (god of prosperity and richness), Pangu and many others.", "In the early decades of the 21st century, the Chinese government has been engaged in a rehabilitation of folk cults — formally recognizing them as \"folk beliefs\" (a category different from that of doctrinal religions), and often reconstructing them into forms of \"highly curated\" civil religion — as well as in a national and international promotion of Buddhism.", "China is home to many of the world's tallest religious statues, representing either deities of Chinese folk religion or enlightened beings of Buddhism; the tallest of all is the Spring Temple Buddha in Henan.Statistics on religious affiliation in China are difficult to gather due to complex and varying definitions of \"religion\" and \"belief\" and the unorganized, diffusive nature of Chinese religious traditions.", "Scholars note that in China there is no clear boundary between the three doctrines and local folk religious practices.", "Chinese religions or some of their currents are also definable as non-theistic and humanistic, since they do not hold that divine creativity is completely transcendent, but that it is inherent in the world and in particular in the human being.", "According to studies published in 2023, compiling reliable demographic analyses holden throughout the 2010s and the early 2020s, 70% of the Chinese population believes in or practices Chinese folk religion; among them, with an approach of non-exclusivity, 33.4% may be identified as Buddhists, 19.6% as Taoists, and 17.7% as adherents of other types of folk religion.", "Of the remaining population, 25.2% are fully non-believers or atheists, 2.5% are adherents of Christianity, and 1.6% are adherents of Islam.", "Chinese folk religion also comprises a variety of salvationist doctrinal organized movements which emerged since the Song dynasty.", "In China, there are also various ethnic minority groups who maintain their own indigenous religions, while sects of the major religions specifically connected to certain ethnic groups include Tibetan Buddhism among Tibetans and Mongols, and Islam among the Hui, Uyghur, Kazakh, and Kyrgyz peoples, and other ethnicities in the northern and northwestern regions of the country." ], [ "Culture and society", "A moon gate in a Chinese gardenSince ancient times, Chinese culture has been heavily influenced by Confucianism.", "Chinese culture, in turn, has heavily influenced East Asia and Southeast Asia.", "For much of the country's dynastic era, opportunities for social advancement could be provided by high performance in the prestigious imperial examinations, which have their origins in the Han dynasty.", "The literary emphasis of the exams affected the general perception of cultural refinement in China, such as the belief that calligraphy, poetry and painting were higher forms of art than dancing or drama.", "Chinese culture has long emphasized a sense of deep history and a largely inward-looking national perspective.", "Examinations and a culture of merit remain greatly valued in China today.Fenghuang County, an ancient town that harbors many architectural remains of Ming and Qing stylesToday, the Chinese government has accepted numerous elements of traditional Chinese culture as being integral to Chinese society.", "With the rise of Chinese nationalism and the end of the Cultural Revolution, various forms of traditional Chinese art, literature, music, film, fashion and architecture have seen a vigorous revival, and folk and variety art in particular have sparked interest nationally and even worldwide.", "Access to foreign media remains heavily restricted.=== Tourism ===China received 65.7 million international visitors in 2019, and in 2018 was the fourth-most-visited country in the world.", "It also experiences an enormous volume of domestic tourism; Chinese tourists made an estimated 6 billion travels within the country in 2019.China hosts the world's second-largest number of World Heritage Sites (56) after Italy, and is one of the most popular tourist destinations (first in the Asia-Pacific).=== Literature ===The stories in ''Journey to the West'' are common themes in Peking opera.Chinese literature is based on the literature of the Zhou dynasty.", "Concepts covered within the Chinese classic texts present a wide range of thoughts and subjects including calendar, military, astrology, herbology, geography and many others.", "Some of the most important early texts include the ''I Ching'' and the ''Shujing'' within the Four Books and Five Classics which served as the Confucian authoritative books for the state-sponsored curriculum in dynastic era.", "Inherited from the ''Classic of Poetry'', classical Chinese poetry developed to its floruit during the Tang dynasty.", "Li Bai and Du Fu opened the forking ways for the poetic circles through romanticism and realism respectively.", "Chinese historiography began with the ''Shiji'', the overall scope of the historiographical tradition in China is termed the Twenty-Four Histories, which set a vast stage for Chinese fictions along with Chinese mythology and folklore.", "Pushed by a burgeoning citizen class in the Ming dynasty, Chinese classical fiction rose to a boom of the historical, town and gods and demons fictions as represented by the Four Great Classical Novels which include ''Water Margin'', ''Romance of the Three Kingdoms'', ''Journey to the West'' and ''Dream of the Red Chamber''.", "Along with the wuxia fictions of Jin Yong and Liang Yusheng, it remains an enduring source of popular culture in the Chinese sphere of influence.In the wake of the New Culture Movement after the end of the Qing dynasty, Chinese literature embarked on a new era with written vernacular Chinese for ordinary citizens.", "Hu Shih and Lu Xun were pioneers in modern literature.", "Various literary genres, such as misty poetry, scar literature, young adult fiction and the xungen literature, which is influenced by magic realism, emerged following the Cultural Revolution.", "Mo Yan, a xungen literature author, was awarded the Nobel Prize in Literature in 2012.=== Cuisine ===Map showing major regional cuisines of ChinaChinese cuisine is highly diverse, drawing on several millennia of culinary history and geographical variety, in which the most influential are known as the \"Eight Major Cuisines\", including Sichuan, Cantonese, Jiangsu, Shandong, Fujian, Hunan, Anhui, and Zhejiang cuisines.", "Chinese cuisine is known for its breadth of cooking methods and ingredients.", "China's staple food is rice in the northeast and south, and wheat-based breads and noodles in the north.", "Bean products such as tofu and soy milk remain a popular source of protein.", "Pork is now the most popular meat in China, accounting for about three-fourths of the country's total meat consumption.", "There is also the vegetarian Buddhist cuisine and the pork-free Chinese Islamic cuisine.", "Chinese cuisine, due to the area's proximity to the ocean and milder climate, has a wide variety of seafood and vegetables.", "Offshoots of Chinese food, such as Hong Kong cuisine and American Chinese cuisine, have emerged in the Chinese diaspora.=== Architecture ===Chinese architecture has developed over millennia in China and has remained a vestigial source of perennial influence on the development of East Asian architecture, including in Japan, Korea, and Mongolia.", "and minor influences on the architecture of Southeast and South Asia including the countries of Malaysia, Singapore, Indonesia, Sri Lanka, Thailand, Laos, Cambodia, Vietnam and the Philippines.Chinese architecture is characterized by bilateral symmetry, use of enclosed open spaces, feng shui (e.g.", "directional hierarchies), a horizontal emphasis, and an allusion to various cosmological, mythological or in general symbolic elements.", "Chinese architecture traditionally classifies structures according to type, ranging from ''pagodas'' to palaces.Chinese architecture varies widely based on status or affiliation, such as whether the structures were constructed for emperors, commoners, or for religious purposes.", "Other variations in Chinese architecture are shown in vernacular styles associated with different geographic regions and different ethnic heritages, such as the stilt houses in the south, the Yaodong buildings in the northwest, the yurt buildings of nomadic people, and the Siheyuan buildings in the north.=== Music ===Chinese music covers a highly diverse range of music from traditional music to modern music.", "Chinese music dates back before the pre-imperial times.", "Traditional Chinese musical instruments were traditionally grouped into eight categories known as ''bayin'' (八音).", "Traditional Chinese opera is a form of musical theatre in China originating thousands of years and has regional style forms such as Beijing and Cantonese opera.", "Chinese pop (C-Pop) includes mandopop and cantopop.", "Chinese hip hop and Hong Kong hip hop have become popular.=== Cinema ===Cinema was first introduced to China in 1896 and the first Chinese film, ''Dingjun Mountain,'' was released in 1905.China has the largest number of movie screens in the world since 2016; China became the largest cinema market in 2020.The top three highest-grossing films in China were ''The Battle at Lake Changjin'' (2021), ''Wolf Warrior 2'' (2017), and ''Hi, Mom'' (2021).=== Fashion ===Hanfu is the historical clothing of the Han people in China.", "The qipao or cheongsam is a popular Chinese female dress.", "The hanfu movement has been popular in contemporary times and seeks to revitalize Hanfu clothing.", "China Fashion Week is the country's only national-level fashion festival.=== Sports ===Go is an abstract strategy board game for two players, in which the aim is to surround more territory than the opponent, and which was invented in China more than 2,500 years ago.China has one of the oldest sporting cultures.", "There is evidence that archery (''shèjiàn'') was practiced during the Western Zhou dynasty.", "Swordplay (''jiànshù'') and ''cuju'', a sport loosely related to association football date back to China's early dynasties as well.Physical fitness is widely emphasized in Chinese culture, with morning exercises such as ''qigong'' and tai chi widely practiced, and commercial gyms and private fitness clubs are gaining popularity.", "Basketball is the most popular spectator sport in China.", "The Chinese Basketball Association and the American National Basketball Association also have a huge national following amongst the Chinese populace, with native-born and NBA-bound Chinese players and well-known national household names such as Yao Ming and Yi Jianlian being held in high esteem.", "China's professional football league, known as Chinese Super League, is the largest football market in East Asia.", "Other popular sports include martial arts, table tennis, badminton, swimming and snooker.", "China is home to a huge number of cyclists, with an estimated 470 million bicycles .", "China has the world's largest esports market.", "Many more traditional sports, such as dragon boat racing, Mongolian-style wrestling and horse racing are also popular.China has participated in the Olympic Games since 1932, although it has only participated as the PRC since 1952.China hosted the 2008 Summer Olympics in Beijing, where its athletes received 48 gold medals – the highest number of any participating nation that year.", "China also won the most medals at the 2012 Summer Paralympics, with 231 overall, including 95 gold.", "In 2011, Shenzhen hosted the 2011 Summer Universiade.", "China hosted the 2013 East Asian Games in Tianjin and the 2014 Summer Youth Olympics in Nanjing, the first country to host both regular and Youth Olympics.", "Beijing and its nearby city Zhangjiakou collaboratively hosted the 2022 Winter Olympics, making Beijing the first dual Olympic city by holding both the Summer Olympics and the Winter Olympics." ], [ "See also", "* Outline of China" ], [ "Notes" ], [ "References" ], [ "Sources" ], [ "Further reading" ], [ "External links", "=== Government ===* The Central People's Government of People's Republic of China === General information ===* China at a Glance from ''People's Daily''* * Country profile – China at BBC News* China.", "''The World Factbook''.", "Central Intelligence Agency.", "* China, People's Republic of from ''UCB Libraries GovPubs''* === Maps ===* Google Maps—China* *" ] ]

[ [ "California" ], [ "Introduction", "'''California''' is a state in the Western region of the United States.", "It borders Oregon to the north, Nevada and Arizona to the east, and the Mexican state of Baja California to the south; it has a coastline along the Pacific Ocean to the west.", "With over 38.9million residents across a total area of approximately , it is the most populous U.S. state, the third-largest U.S. state by area, and the most populated subnational entity in North America.The Greater Los Angeles and San Francisco Bay areas in California are the nation's second and fifth-most populous urban regions respectively.", "Greater Los Angeles has over 18.7 million residents and the San Francisco Bay Area has over 9.6 million residents.", "Los Angeles is the state's most populous city and the nation's second-most populous city.", "San Francisco is the second-most densely populated major city in the country.", "Los Angeles County is the country's most populous county, and San Bernardino County is the nation's largest county by area.", "Sacramento is the state's capital city.California's economy is the largest of any state within the United States, with a $3.6 trillion gross state product (GSP) .", "It is the largest sub-national economy in the world.", "If California were a sovereign nation, it would rank as the world's fifth-largest economy , behind India and ahead of the United Kingdom, as well as the 37th most populous.", "The Greater Los Angeles area and the San Francisco area are the nation's second- and fourth-largest urban economies ($1.0trillion and $0.6trillion respectively ).", "The San Francisco Bay Area Combined Statistical Area had the nation's highest gross domestic product per capita ($106,757) among large primary statistical areas in 2018, and is home to five of the world's ten largest companies by market capitalization and four of the world's ten richest people.", "Slightly over 84 percent of the state's residents 25 or older hold a high school degree, the lowest high school education rate of all 50 states.Prior to European colonization, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America, and the indigenous peoples of California constituted the highest Native American population density north of what is now Mexico.", "European exploration in the 16th and 17th centuries led to the colonization of California by the Spanish Empire.", "In 1804, it was included in Alta California province within the Viceroyalty of New Spain.", "The area became a part of Mexico in 1821, following its successful war for independence, but was ceded to the United States in 1848 after the Mexican–American War.", "The California Gold Rush started in 1848 and led to dramatic social and demographic changes.", "The western portion of Alta California was then organized and admitted as the 31st state on September 9, 1850, as a free state, following the Compromise of 1850.Notable contributions to popular culture, ranging from entertainment, sports, music, and fashion, have their origins in California.", "The state also has made substantial contributions in the fields of communication, information, innovation, education, environmentalism, entertainment, economics, politics, technology, and religion.", "California is the home of Hollywood, the oldest and one of the largest film industries in the world, profoundly influencing global entertainment.", "It is considered the origin of the American film industry, hippie counterculture, beach and car culture, the personal computer, the internet, fast food, diners, burger joints, skateboarding, and the fortune cookie, among other inventions.", "The San Francisco Bay Area and the Greater Los Angeles Area are widely seen as the centers of the global technology and U.S. film industries, respectively.", "California's economy is very diverse.", "California's agricultural industry has the highest output of any U.S. state, and is led by its dairy, almonds, and grapes.", "With the busiest ports in the country (Los Angeles and Long Beach), California plays a pivotal role in the global supply chain, hauling in about 40% of all goods imported to the United States.The state's extremely diverse geography ranges from the Pacific Coast and metropolitan areas in the west to the Sierra Nevada mountains in the east, and from the redwood and Douglas fir forests in the northwest to the Mojave Desert in the southeast.", "Two-thirds of the nation's earthquake risk lies in California.", "The Central Valley, a fertile agricultural area, dominates the state's center.", "California is well known for its warm Mediterranean climate along the coast and monsoon seasonal weather inland.", "The large size of the state results in climates that vary from moist temperate rainforest in the north to arid desert in the interior, as well as snowy alpine in the mountains.", "Droughts and wildfires are an ongoing issue for the state." ], [ "Etymology", "Queen Calafia, originate in the 1510 epic ''Las Sergas de Esplandián'', written by Garci Rodríguez de Montalvo.The Spaniards gave the name to the peninsula of Baja California and to Alta California, the latter region becoming the present-day state of California.The name derived from the mythical island of California in the fictional story of Queen Calafia, as recorded in a 1510 work ''The Adventures of Esplandián'' by Castilian author Garci Rodríguez de Montalvo.", "This work was the fifth in a popular Spanish chivalric romance series that began with .", "Queen Calafia's kingdom was said to be a remote land rich in gold and pearls, inhabited by beautiful Black women who wore gold armor and lived like Amazons, as well as griffins and other strange beasts.", "In the fictional paradise, the ruler Queen Calafia fought alongside Muslims and her name may have been chosen to echo the Muslim title caliph, used for Muslim leaders.Official abbreviations of the state's name include CA, Cal., Calif., and US-CA." ], [ "History", "indigenous Californian tribes and languages at the time of European contact===Indigenous===California was one of the most culturally and linguistically diverse areas in pre-Columbian North America.", "Historians generally agree that there were at least 300,000 people living in California prior to European colonization.", "The indigenous peoples of California included more than 70 distinct ethnic groups, inhabiting environments ranging from mountains and deserts to islands and redwood forests.Living in these diverse geographic areas, the indigenous peoples developed complex forms of ecosystem management, including forest gardening to ensure the regular availability of food and medicinal plants.", "This was a form of sustainable agriculture.", "To mitigate destructive large wildfires from ravaging the natural environment, indigenous peoples developed a practice of controlled burning.", "This practice was recognized for its benefits by the California government in 2022.These groups were also diverse in their political organization, with bands, tribes, villages, and, on the resource-rich coasts, large chiefdoms, such as the Chumash, Pomo and Salinan.", "Trade, intermarriage, craft specialists, and military alliances fostered social and economic relationships between many groups.", "Although nations would sometimes war, most armed conflicts were between groups of men for vengeance.", "Acquiring territory was not usually the purpose of these small-scale battles.Men and women generally had different roles in society.", "Women were often responsible for weaving, harvesting, processing, and preparing food, while men for hunting and other forms of physical labor.", "Most societies also had roles for people whom the Spanish referred to as ''joyas'', who they saw as \"men who dressed as women\".", "''Joyas'' were responsible for death, burial, and mourning rituals, and they performed women's social roles.", "Indigenous societies had terms such as two-spirit to refer to them.", "The Chumash referred to them as '''aqi.''", "The early Spanish settlers detested and sought to eliminate them.Between 1846 and 1873, U.S. government agents and private settlers perpetrated many massacres against indigenous Californians.", "At least 9,456 were killed with estimates as high as 100,000 deaths.The indigenous peoples saw declines in their population under Spanish, Mexican, and American rule.", "A major cause was Eurasian diseases to which they had not yet developed a natural immunity.", "After California became a part of the United States, they were often forcibly removed from their lands by American settlers and ''de facto'' enslaved.", "Many reservations to which they were moved were not sustainable.", "Militias hired to protect settlers also perpetrated numerous massacres.", "There has been significant discussion over the scale of the Native American losses and whether it should be labeled an ethnic cleansing or genocide.", "Supporters of ''ethnic cleansing'' point out that most of the deaths resulted from diseases and settler actions.", "Supporters of ''genocide'' point to the role of the government in initiating and enabling the atrocities.", "In 2019, the 40th governor of California, Gavin Newsom apologized to the indigenous peoples of California for the events.", "===Spanish period===Portuguese explorer Juan Rodríguez Cabrillo claiming California for the Spanish Empire in 1542The first Europeans to explore the coast of California were the members of a Spanish maritime expedition led by Portuguese captain Juan Rodríguez Cabrillo in 1542.Cabrillo was commissioned by Antonio de Mendoza, the Viceroy of New Spain, to lead an expedition up the Pacific coast in search of trade opportunities; they entered San Diego Bay on September 28, 1542, and reached at least as far north as San Miguel Island.", "Privateer and explorer Francis Drake explored and claimed an undefined portion of the California coast in 1579, landing north of the future city of San Francisco.", "The first Asians to set foot on what would be the United States occurred in 1587, when Filipino sailors arrived in Spanish ships at Morro Bay.", "Coincidentally the descendants of the Muslim Caliph Hasan ibn Ali in formerly Islamic Manila and had converted, then mixed Christianity with Islam, upon Spanish conquest, transited through California (Named after a Caliph) on their way to Guerrero, Mexico.", "Sebastián Vizcaíno explored and mapped the coast of California in 1602 for New Spain, putting ashore in Monterey.", "Despite the on-the-ground explorations of California in the 16th century, Rodríguez's idea of California as an island persisted.", "Such depictions appeared on many European maps well into the 18th century.The Portolá expedition of 1769–70 was a pivotal event in the Spanish colonization of California, resulting in the establishment of numerous missions, presidios, and pueblos.", "The military and civil contingent of the expedition was led by Gaspar de Portolá, who traveled over land from Sonora into California, while the religious component was headed by Junípero Serra, who came by sea from Baja California.", "In 1769, Portolá and Serra established Mission San Diego de Alcalá and the Presidio of San Diego, the first religious and military settlements founded by the Spanish in California.", "By the end of the expedition in 1770, they would establish the Presidio of Monterey and Mission San Carlos Borromeo de Carmelo on Monterey Bay.", "Junípero Serra conducting the first Mass in Monterey Bay in 1770After the Portolà expedition, Spanish missionaries led by Father-President Serra set out to establish 21 Spanish missions of California along El Camino Real (\"The Royal Road\") and along the California coast, 16 sites of which having been chosen during the Portolá expedition.", "Numerous major cities in California grew out of missions, including San Francisco (Mission San Francisco de Asís), San Diego (Mission San Diego de Alcalá), Ventura (Mission San Buenaventura), or Santa Barbara (Mission Santa Barbara), among others.Juan Bautista de Anza led a similarly important expedition throughout California in 1775–76, which would extend deeper into the interior and north of California.", "The Anza expedition selected numerous sites for missions, presidios, and pueblos, which subsequently would be established by settlers.", "Gabriel Moraga, a member of the expedition, would also christen many of California's prominent rivers with their names in 1775–1776, such as the Sacramento River and the San Joaquin River.", "After the expedition, Gabriel's son, José Joaquín Moraga, would found the pueblo of San Jose in 1777, making it the first civilian-established city in California.The Spanish founded Mission San Juan Capistrano in 1776, the third to be established of California's missions.During this same period, sailors from the Russian Empire explored along the northern coast of California.", "In 1812, the Russian-American Company established a trading post and small fortification at Fort Ross on the North Coast.", "Fort Ross was primarily used to supply Russia's Alaskan colonies with food supplies.", "The settlement did not meet much success, failing to attract settlers or establish long term trade viability, and was abandoned by 1841.During the War of Mexican Independence, Alta California was largely unaffected and uninvolved in the revolution, though many Californios supported independence from Spain, which many believed had neglected California and limited its development.", "Spain's trade monopoly on California had limited local trade prospects.", "Following Mexican independence, California ports were freely able to trade with foreign merchants.", "Governor Pablo Vicente de Solá presided over the transition from Spanish colonial rule to independent Mexican rule.===Mexican period===The flag used by Californio leader Juan Bautista Alvarado's 1836 California independence movementIn 1821, the Mexican War of Independence gave the Mexican Empire (which included California) independence from Spain.", "For the next 25 years, Alta California remained a remote, sparsely populated, northwestern administrative district of the newly independent country of Mexico, which shortly after independence became a republic.", "The missions, which controlled most of the best land in the state, were secularized by 1834 and became the property of the Mexican government.", "The governor granted many square leagues of land to others with political influence.", "These huge ''ranchos'' or cattle ranches emerged as the dominant institutions of Mexican California.", "The ranchos developed under ownership by Californios (Hispanics native of California) who traded cowhides and tallow with Boston merchants.", "Beef did not become a commodity until the 1849 California Gold Rush.From the 1820s, trappers and settlers from the United States and Canada began to arrive in Northern California.", "These new arrivals used the Siskiyou Trail, California Trail, Oregon Trail and Old Spanish Trail to cross the rugged mountains and harsh deserts in and surrounding California.", "The early government of the newly independent Mexico was highly unstable, and in a reflection of this, from 1831 onwards, California also experienced a series of armed disputes, both internal and with the central Mexican government.", "During this tumultuous political period Juan Bautista Alvarado was able to secure the governorship during 1836–1842.The military action which first brought Alvarado to power had momentarily declared California to be an independent state, and had been aided by Anglo-American residents of California, including Isaac Graham.", "In 1840, one hundred of those residents who did not have passports were arrested, leading to the Graham Affair, which was resolved in part with the intercession of Royal Navy officials.Mariano G. Vallejo reviewing his troops in the Sonoma Plaza, 1846One of the largest ranchers in California was John Marsh.", "After failing to obtain justice against squatters on his land from the Mexican courts, he determined that California should become part of the United States.", "Marsh conducted a letter-writing campaign espousing the California climate, the soil, and other reasons to settle there, as well as the best route to follow, which became known as \"Marsh's route\".", "His letters were read, reread, passed around, and printed in newspapers throughout the country, and started the first wagon trains rolling to California.", "He invited immigrants to stay on his ranch until they could get settled, and assisted in their obtaining passports.After ushering in the period of organized emigration to California, Marsh became involved in a military battle between the much-hated Mexican general, Manuel Micheltorena and the California governor he had replaced, Juan Bautista Alvarado.", "The armies of each met at the Battle of Providencia near Los Angeles.", "Marsh had been forced against his will to join Micheltorena's army.", "Ignoring his superiors, during the battle, he signaled the other side for a parley.", "There were many settlers from the United States fighting on both sides.", "He convinced each side that they had no reason to be fighting each other.", "As a result of Marsh's actions, they abandoned the fight, Micheltorena was defeated, and California-born Pio Pico was returned to the governorship.", "This paved the way to California's ultimate acquisition by the United States.===U.S.", "Conquest and the California Republic===The 1846 Bear Flag Revolt declared the California Republic and prefaced the American conquest of California.In 1846, a group of American settlers in and around Sonoma rebelled against Mexican rule during the Bear Flag Revolt.", "Afterward, rebels raised the Bear Flag (featuring a bear, a star, a red stripe and the words \"California Republic\") at Sonoma.", "The Republic's only president was William B. Ide, who played a pivotal role during the Bear Flag Revolt.", "This revolt by American settlers served as a prelude to the later American military invasion of California and was closely coordinated with nearby American military commanders.The California Republic was short-lived; the same year marked the outbreak of the Mexican–American War (1846–1848).Commodore John D. Sloat of the United States Navy sailed into Monterey Bay in 1846 and began the U.S. military invasion of California, with Northern California capitulating in less than a month to the United States forces.", "In Southern California, Californios continued to resist American forces.", "Notable military engagements of the conquest include the Battle of San Pasqual and the Battle of Dominguez Rancho in Southern California, as well as the Battle of Olómpali and the Battle of Santa Clara in Northern California.", "After a series of defensive battles in the south, the Treaty of Cahuenga was signed by the Californios on January 13, 1847, securing a censure and establishing de facto American control in California.===Early American period===The Treaty of Cahuenga, signed in 1847 by Californio Andrés Pico and American John C. Frémont, was a ceasefire that ended the U.S. Conquest of California.Following the Treaty of Guadalupe Hidalgo (February 2, 1848) that ended the war, the westernmost portion of the annexed Mexican territory of Alta California soon became the American state of California, and the remainder of the old territory was then subdivided into the new American Territories of Arizona, Nevada, Colorado and Utah.", "The even more lightly populated and arid lower region of old Baja California remained as a part of Mexico.", "In 1846, the total settler population of the western part of the old Alta California had been estimated to be no more than 8,000, plus about 100,000 Native Americans, down from about 300,000 before Hispanic settlement in 1769.In 1848, only one week before the official American annexation of the area, gold was discovered in California, this being an event which was to forever alter both the state's demographics and its finances.", "Soon afterward, a massive influx of immigration into the area resulted, as prospectors and miners arrived by the thousands.", "The population burgeoned with United States citizens, Europeans, Middle Easterns, Chinese and other immigrants during the great California Gold Rush.", "By the time of California's application for statehood in 1850, the settler population of California had multiplied to 100,000.By 1854, more than 300,000 settlers had come.", "Between 1847 and 1870, the population of San Francisco increased from 500 to 150,000.The seat of government for California under Spanish and later Mexican rule had been located in Monterey from 1777 until 1845.Pio Pico, the last Mexican governor of Alta California, had briefly moved the capital to Los Angeles in 1845.The United States consulate had also been located in Monterey, under consul Thomas O. Larkin.In 1849, a state Constitutional Convention was first held in Monterey.", "Among the first tasks of the convention was a decision on a location for the new state capital.", "The first full legislative sessions were held in San Jose (1850–1851).", "Subsequent locations included Vallejo (1852–1853), and nearby Benicia (1853–1854); these locations eventually proved to be inadequate as well.", "The capital has been located in Sacramento since 1854 with only a short break in 1862 when legislative sessions were held in San Francisco due to flooding in Sacramento.Once the state's Constitutional Convention had finalized its state constitution, it applied to the U.S. Congress for admission to statehood.", "On September 9, 1850, as part of the Compromise of 1850, California became a free state and September9 a state holiday.During the American Civil War (1861–1865), California sent gold shipments eastward to Washington in support of the Union.", "However, due to the existence of a large contingent of pro-South sympathizers within the state, the state was not able to muster any full military regiments to send eastwards to officially serve in the Union war effort.", "Still, several smaller military units within the Union army, such as the \"California 100 Company\", were unofficially associated with the state of California due to a majority of their members being from California.At the time of California's admission into the Union, travel between California and the rest of the continental United States had been a time-consuming and dangerous feat.", "Nineteen years later, and seven years after it was greenlighted by President Lincoln, the first transcontinental railroad was completed in 1869.California was then reachable from the eastern States in a week's time.", "Much of the state was extremely well suited to fruit cultivation and agriculture in general.", "Vast expanses of wheat, other cereal crops, vegetable crops, cotton, and nut and fruit trees were grown (including oranges in Southern California), and the foundation was laid for the state's prodigious agricultural production in the Central Valley and elsewhere.", "In the nineteenth century, a large number of migrants from China traveled to the state as part of the Gold Rush or to seek work.", "Even though the Chinese proved indispensable in building the transcontinental railroad from California to Utah, perceived job competition with the Chinese led to anti-Chinese riots in the state, and eventually the US ended migration from China partially as a response to pressure from California with the 1882 Chinese Exclusion Act.===1900–present===View of the destruction from the 1906 San Francisco earthquakeIn the twentieth century, thousands of Japanese people migrated to the US and California specifically to attempt to purchase and own land in the state.", "However, the state in 1913 passed the Alien Land Act, excluding Asian immigrants from owning land.", "During World War II, Japanese Americans in California were interned in concentration camps such as at Tule Lake and Manzanar.", "In 2020, California officially apologized for this internment.Migration to California accelerated during the early 20th century with the completion of major transcontinental highways like the Lincoln Highway and Route 66.In the period from 1900 to 1965, the population grew from fewer than one million to the greatest in the Union.", "In 1940, the Census Bureau reported California's population as 6.0% Hispanic, 2.4% Asian, and 89.5% non-Hispanic white.To meet the population's needs, major engineering feats like the California and Los Angeles Aqueducts; the Oroville and Shasta Dams; and the Bay and Golden Gate Bridges were built across the state.", "The state government also adopted the California Master Plan for Higher Education in 1960 to develop a highly efficient system of public education.Hollywood studios, like Paramount Pictures, helped transform Hollywood into the world capital of film and helped solidify Los Angeles as a global economic hub.Meanwhile, attracted to the mild Mediterranean climate, cheap land, and the state's wide variety of geography, filmmakers established the studio system in Hollywood in the 1920s.", "California manufactured 8.7 percent of total United States military armaments produced during World War II, ranking third (behind New York and Michigan) among the 48 states.", "California however easily ranked first in production of military ships during the war (transport, cargo, merchant ships such as Liberty ships, Victory ships, and warships) at drydock facilities in San Diego, Los Angeles, and the San Francisco Bay Area.", "Due to the hiring opportunities California offered during the conflict, the population of the state greatly multiplied from the immigration it received due to the work offered in its war factories, military bases, and training facilities.", "After World War II, California's economy greatly expanded due to strong aerospace and defense industries, whose size decreased following the end of the Cold War.", "Stanford University and its Dean of Engineering Frederick Terman began encouraging faculty and graduates to stay in California instead of leaving the state, and develop a high-tech region in the area now known as Silicon Valley.", "As a result of these efforts, California is regarded as a world center of the entertainment and music industries, of technology, engineering, and the aerospace industry, and as the United States center of agricultural production.", "Just before the Dot Com Bust, California had the fifth-largest economy in the world among nations.In the mid and late twentieth century, a number of race-related incidents occurred in the state.", "Tensions between police and African Americans, combined with unemployment and poverty in inner cities, led to violent riots, such as the 1965 Watts riots and 1992 Rodney King riots.", "California was also the hub of the Black Panther Party, a group known for arming African Americans to defend against racial injustice and for organizing free breakfast programs for schoolchildren.", "Additionally, Mexican, Filipino, and other migrant farm workers rallied in the state around Cesar Chavez for better pay in the 1960s and 1970s.Civil rights activist Cesar Chavez, flanked by Brown Berets, at a 1971 rally during the Chicano movementDuring the 20th century, two great disasters happened in California.", "The 1906 San Francisco earthquake and 1928 St. Francis Dam flood remain the deadliest in U.S. history.Although air pollution problems have been reduced, health problems associated with pollution have continued.", "The brown haze known as \"smog\" has been substantially abated after the passage of federal and state restrictions on automobile exhaust.An energy crisis in 2001 led to rolling blackouts, soaring power rates, and the importation of electricity from neighboring states.", "Southern California Edison and Pacific Gas and Electric Company came under heavy criticism.Housing prices in urban areas continued to increase; a modest home which in the 1960s cost $25,000 would cost half a million dollars or more in urban areas by 2005.More people commuted longer hours to afford a home in more rural areas while earning larger salaries in the urban areas.", "Speculators bought houses they never intended to live in, expecting to make a huge profit in a matter of months, then rolling it over by buying more properties.", "Mortgage companies were compliant, as everyone assumed the prices would keep rising.", "The bubble burst in 2007–8 as housing prices began to crash and the boom years ended.", "Hundreds of billions in property values vanished and foreclosures soared as many financial institutions and investors were badly hurt.iPhone by Apple founder Steve Jobs in Silicon Valley, the largest tech hub in the worldIn the twenty-first century, droughts and frequent wildfires attributed to climate change have occurred in the state.", "From 2011 to 2017, a persistent drought was the worst in its recorded history.", "The 2018 wildfire season was the state's deadliest and most destructive, most notably Camp Fire.One of the first confirmed COVID-19 cases in the United States that occurred in California was first of which was confirmed on January 26, 2020.Meaning, all of the early confirmed cases were persons who had recently travelled to China in Asia, as testing was restricted to this group.", "On this January 29, 2020, as disease containment protocols were still being developed, the U.S. Department of State evacuated 195 persons from Wuhan, China aboard a chartered flight to March Air Reserve Base in Riverside County, and in this process, it may have granted and conferred to escalated within the land and the US at cosmic.", "On February 5, 2020, the U.S. evacuated 345 more citizens from Hubei Province to two military bases in California, Travis Air Force Base in Solano County and Marine Corps Air Station Miramar, San Diego, where they were quarantined for 14 days.", "A state of emergency was largely declared in this state of the nation on March 4, 2020, and as of February 24, 2021, remains in effect.", "A mandatory statewide stay-at-home order was issued on March 19, 2020, due to increase, which was ended on January 25, 2021, allowing citizens to return to normal life.", "On April 6, 2021, the state announced plans to fully reopen the economy by June 15, 2021.Cultural and language revitalization efforts among indigenous Californians have progressed among several tribes as of 2022.Some land returns to indigenous stewardship have occurred throughout California.", "In 2022, the largest dam removal and river restoration project in US history was announced for the Klamath River as a win for California tribes." ], [ "Geography", "Topographic map of CaliforniaCovering an area of , California is the third-largest state in the United States in area, after Alaska and Texas.", "California is one of the most geographically diverse states in the union and is often geographically bisected into two regions, Southern California, comprising the ten southernmost counties, and Northern California, comprising the 48 northernmost counties.", "It is bordered by Oregon to the north, Nevada to the east and northeast, Arizona to the southeast, the Pacific Ocean to the west and shares an international border with the Mexican state of Baja California to the south (with which it makes up part of The Californias region of North America, alongside Baja California Sur).In the middle of the state lies the California Central Valley, bounded by the Sierra Nevada in the east, the coastal mountain ranges in the west, the Cascade Range to the north and by the Tehachapi Mountains in the south.", "The Central Valley is California's productive agricultural heartland.Divided in two by the Sacramento-San Joaquin River Delta, the northern portion, the Sacramento Valley serves as the watershed of the Sacramento River, while the southern portion, the San Joaquin Valley is the watershed for the San Joaquin River.", "Both valleys derive their names from the rivers that flow through them.", "With dredging, the Sacramento and the San Joaquin Rivers have remained deep enough for several inland cities to be seaports.Big Sur, on the Central CoastYosemite, in the Sierra NevadaThe Sacramento-San Joaquin River Delta is a critical water supply hub for the state.", "Water is diverted from the delta and through an extensive network of pumps and canals that traverse nearly the length of the state, to the Central Valley and the State Water Projects and other needs.", "Water from the Delta provides drinking water for nearly 23million people, almost two-thirds of the state's population as well as water for farmers on the west side of the San Joaquin Valley.Suisun Bay lies at the confluence of the Sacramento and San Joaquin Rivers.", "The water is drained by the Carquinez Strait, which flows into San Pablo Bay, a northern extension of San Francisco Bay, which then connects to the Pacific Ocean via the Golden Gate strait.The Channel Islands are located off the Southern coast, while the Farallon Islands lie west of San Francisco.The Sierra Nevada (Spanish for \"snowy range\") includes the highest peak in the contiguous 48 states, Mount Whitney, at .", "The range embraces Yosemite Valley, famous for its glacially carved domes, and Sequoia National Park, home to the giant sequoia trees, the largest living organisms on Earth, and the deep freshwater lake, Lake Tahoe, the largest lake in the state by volume.To the east of the Sierra Nevada are Owens Valley and Mono Lake, an essential migratory bird habitat.", "In the western part of the state is Clear Lake, the largest freshwater lake by area entirely in California.", "Although Lake Tahoe is larger, it is divided by the California/Nevada border.", "The Sierra Nevada falls to Arctic temperatures in winter and has several dozen small glaciers, including Palisade Glacier, the southernmost glacier in the United States.Death Valley, in the Mojave DesertSan Miguel, in the Channel IslandsThe Tulare Lake was the largest freshwater lake west of the Mississippi River.", "A remnant of Pleistocene-era Lake Corcoran, Tulare Lake dried up by the early 20th century after its tributary rivers were diverted for agricultural irrigation and municipal water uses.About 45 percent of the state's total surface area is covered by forests, and California's diversity of pine species is unmatched by any other state.", "California contains more forestland than any other state except Alaska.", "Many of the trees in the California White Mountains are the oldest in the world; an individual bristlecone pine is over 5,000 years old.In the south is a large inland salt lake, the Salton Sea.", "The south-central desert is called the Mojave; to the northeast of the Mojave lies Death Valley, which contains the lowest and hottest place in North America, the Badwater Basin at .", "The horizontal distance from the bottom of Death Valley to the top of Mount Whitney is less than .", "Indeed, almost all of southeastern California is arid, hot desert, with routine extreme high temperatures during the summer.", "The southeastern border of California with Arizona is entirely formed by the Colorado River, from which the southern part of the state gets about half of its water.A majority of California's cities are located in either the San Francisco Bay Area or the Sacramento metropolitan area in Northern California; or the Los Angeles area, the Inland Empire, or the San Diego metropolitan area in Southern California.", "The Los Angeles Area, the Bay Area, and the San Diego metropolitan area are among several major metropolitan areas along the California coast.As part of the Ring of Fire, California is subject to tsunamis, floods, droughts, Santa Ana winds, wildfires, and landslides on steep terrain; California also has several volcanoes.", "It has many earthquakes due to several faults running through the state, the largest being the San Andreas Fault.", "About 37,000 earthquakes are recorded each year; most are too small to be felt, but two-thirds of the human risk from earthquakes lies in California.===Climate===Köppen climate types in CaliforniaMost of the state has a Mediterranean climate.", "The cool California Current offshore often creates summer fog near the coast.", "Farther inland, there are colder winters and hotter summers.", "The maritime moderation results in the shoreline summertime temperatures of Los Angeles and San Francisco being the coolest of all major metropolitan areas of the United States and uniquely cool compared to areas on the same latitude in the interior and on the east coast of the North American continent.", "Even the San Diego shoreline bordering Mexico is cooler in summer than most areas in the contiguous United States.", "Just a few miles inland, summer temperature extremes are significantly higher, with downtown Los Angeles being several degrees warmer than at the coast.", "The same microclimate phenomenon is seen in the climate of the Bay Area, where areas sheltered from the ocean experience significantly hotter summers and colder winters in contrast with nearby areas closer to the ocean.California wildfires affect the state yearly.", "In the south, the Santa Ana winds often expand fires and spread smoke over hundreds of miles.Northern parts of the state have more rain than the south.", "California's mountain ranges also influence the climate: some of the rainiest parts of the state are west-facing mountain slopes.", "Coastal northwestern California has a temperate climate, and the Central Valley has a Mediterranean climate but with greater temperature extremes than the coast.", "The high mountains, including the Sierra Nevada, have an alpine climate with snow in winter and mild to moderate heat in summer.California's mountains produce rain shadows on the eastern side, creating extensive deserts.", "The higher elevation deserts of eastern California have hot summers and cold winters, while the low deserts east of the Southern California mountains have hot summers and nearly frostless mild winters.", "Death Valley, a desert with large expanses below sea level, is considered the hottest location in the world; the highest temperature in the world, , was recorded there on July 10, 1913.The lowest temperature in California was on January 20, 1937, in Boca.The table below lists average temperatures for January and August in a selection of places throughout the state; some highly populated and some not.", "This includes the relatively cool summers of the Humboldt Bay region around Eureka, the extreme heat of Death Valley, and the mountain climate of Mammoth in the Sierra Nevada.+Average temperatures and precipitation for selected communities in CaliforniaLocation August(°F) August(°C) January(°F) January(°C) Annualprecipitation(mm/in)Los Angeles 83/64 29/18 66/48 20/8 377/15LAX/LA Beaches 75/64 23/18 65/49 18/9 326/13San Diego 76/67 24/19 65/49 18/9 262/10San Jose 82/58 27/14 58/42 14/5 401/16San Francisco 67/54 20/12 56/46 14/8 538/21Fresno 97/66 34/19 55/38 12/3 292/11Sacramento 91/58 33/14 54/39 12/3 469/18Oakland 73/58 23/14 58/44 14/7 588/23Bakersfield 96/69 36/21 56/39 13/3 165/7Riverside 94/60 35/18 67/39 19/4 260/10Eureka 62/53 16/11 54/41 12/5 960/38Death Valley 115/86 46/30 67/40 19/4 60/2Mammoth Lakes 77/45 25/7 40/15 4/ −9 583/23The wide range of climates leads to a high demand for water.", "Over time, droughts have been increasing due to climate change and overextraction, becoming less seasonal and more year-round, further straining California's electricity supply and water security and having an impact on California business, industry, and agriculture.In 2022, a new state program was created in collaboration with indigenous peoples of California to revive the practice of controlled burns as a way of clearing excessive forest debris and making landscapes more resilient to wildfires.", "Native American use of fire in ecosystem management was outlawed in 1911, yet has now been recognized.===Ecology===Mount Whitney, in the Sierra Nevada, is the highest mountain in the contiguous United States.California is one of the ecologically richest and most diverse parts of the world, and includes some of the most endangered ecological communities.", "California is part of the Nearctic realm and spans a number of terrestrial ecoregions.California's large number of endemic species includes relict species, which have died out elsewhere, such as the Catalina ironwood (''Lyonothamnus floribundus'').", "Many other endemics originated through differentiation or adaptive radiation, whereby multiple species develop from a common ancestor to take advantage of diverse ecological conditions such as the California lilac (''Ceanothus'').", "Many California endemics have become endangered, as urbanization, logging, overgrazing, and the introduction of exotic species have encroached on their habitat.===Flora and fauna===Giant Sequoias, native to California, are the largest trees in the world.", "Shown is the Grizzly Giant in Yosemite.California boasts several superlatives in its collection of flora: the largest trees, the tallest trees, and the oldest trees.", "California's native grasses are perennial plants, and there are close to hundred succulent species native to the state.", "After European contact, these were generally replaced by invasive species of European annual grasses; and, in modern times, California's hills turn a characteristic golden-brown in summer.Because California has the greatest diversity of climate and terrain, the state has six life zones which are the lower Sonoran Desert; upper Sonoran (foothill regions and some coastal lands), transition (coastal areas and moist northeastern counties); and the Canadian, Hudsonian, and Arctic Zones, comprising the state's highest elevations.Plant life in the dry climate of the lower Sonoran zone contains a diversity of native cactus, mesquite, and paloverde.", "The Joshua tree is found in the Mojave Desert.", "Flowering plants include the dwarf desert poppy and a variety of asters.", "Fremont cottonwood and valley oak thrive in the Central Valley.", "The upper Sonoran zone includes the chaparral belt, characterized by forests of small shrubs, stunted trees, and herbaceous plants.", "''Nemophila'', mint, ''Phacelia'', ''Viola'', and the California poppy (''Eschscholzia californica'', the state flower) also flourish in this zone, along with the lupine, more species of which occur here than anywhere else in the world.A California sea lion in La JollaThe transition zone includes most of California's forests with the redwood (''Sequoia sempervirens'') and the \"big tree\" or giant sequoia (''Sequoiadendron giganteum''), among the oldest living things on earth (some are said to have lived at least 4,000 years).", "Tanbark oak, California laurel, sugar pine, madrona, broad-leaved maple, and Douglas-fir also grow here.", "Forest floors are covered with swordfern, alumnroot, barrenwort, and trillium, and there are thickets of huckleberry, azalea, elder, and wild currant.", "Characteristic wild flowers include varieties of mariposa, tulip, and tiger and leopard lilies.The high elevations of the Canadian zone allow the Jeffrey pine, red fir, and lodgepole pine to thrive.", "Brushy areas are abundant with dwarf manzanita and ceanothus; the unique Sierra puffball is also found here.", "Right below the timberline, in the Hudsonian zone, the whitebark, foxtail, and silver pines grow.", "At about , begins the Arctic zone, a treeless region whose flora include a number of wildflowers, including Sierra primrose, yellow columbine, alpine buttercup, and alpine shooting star.Palm trees are a well-known feature of California, particularly in Southern California and Los Angeles; many species have been imported, though the ''Washington filifera'' (commonly known as the ''California fan palm'') is native to the state, mainly growing in the Colorado Desert oases.", "Other common plants that have been introduced to the state include the eucalyptus, acacia, pepper tree, geranium, and Scotch broom.", "The species that are federally classified as endangered are the Contra Costa wallflower, Antioch Dunes evening primrose, Solano grass, San Clemente Island larkspur, salt marsh bird's beak, McDonald's rock-cress, and Santa Barbara Island liveforever.", ", 85 plant species were listed as threatened or endangered.A Tule Elk in the San Joaquin ValleyIn the deserts of the lower Sonoran zone, the mammals include the jackrabbit, kangaroo rat, squirrel, and opossum.", "Common birds include the owl, roadrunner, cactus wren, and various species of hawk.", "The area's reptilian life include the sidewinder viper, desert tortoise, and horned toad.", "The upper Sonoran zone boasts mammals such as the antelope, brown-footed woodrat, and ring-tailed cat.", "Birds unique to this zone are the California thrasher, bushtit, and California condor.In the transition zone, there are Colombian black-tailed deer, black bears, gray foxes, cougars, bobcats, and Roosevelt elk.", "Reptiles such as the garter snakes and rattlesnakes inhabit the zone.", "In addition, amphibians such as the water puppy and redwood salamander are common too.", "Birds such as the kingfisher, chickadee, towhee, and hummingbird thrive here as well.The Canadian zone mammals include the mountain weasel, snowshoe hare, and several species of chipmunks.", "Conspicuous birds include the blue-fronted jay, mountain chickadee, hermit thrush, American dipper, and Townsend's solitaire.", "As one ascends into the Hudsonian zone, birds become scarcer.", "While the gray-crowned rosy finch is the only bird native to the high Arctic region, other bird species such as Anna's hummingbird and Clark's nutcracker.", "Principal mammals found in this region include the Sierra coney, white-tailed jackrabbit, and the bighorn sheep.", ", the bighorn sheep was listed as endangered by the U.S.", "Fish and Wildlife Service.", "The fauna found throughout several zones are the mule deer, coyote, mountain lion, northern flicker, and several species of hawk and sparrow.Methuselah is the oldest tree in the world, found in the Ancient Bristlecone Pine Forest of Inyo National Forest.Aquatic life in California thrives, from the state's mountain lakes and streams to the rocky Pacific coastline.", "Numerous trout species are found, among them rainbow, golden, and cutthroat.", "Migratory species of salmon are common as well.", "Deep-sea life forms include sea bass, yellowfin tuna, barracuda, and several types of whale.", "Native to the cliffs of northern California are seals, sea lions, and many types of shorebirds, including migratory species., 118 California animals were on the federal endangered list; 181 plants were listed as endangered or threatened.", "Endangered animals include the San Joaquin kitfox, Point Arena mountain beaver, Pacific pocket mouse, salt marsh harvest mouse, Morro Bay kangaroo rat (and five other species of kangaroo rat), Amargosa vole, California least tern, California condor, loggerhead shrike, San Clemente sage sparrow, San Francisco garter snake, five species of salamander, three species of chub, and two species of pupfish.", "Eleven butterflies are also endangered and two that are threatened are on the federal list.", "Among threatened animals are the coastal California gnatcatcher, Paiute cutthroat trout, southern sea otter, and northern spotted owl.", "California has a total of of National Wildlife Refuges.", ", 123 California animals were listed as either endangered or threatened on the federal list.", "Also, , 178 species of California plants were listed either as endangered or threatened on this federal list.===Rivers===San Francisco Bay (center left) and the California Delta (top right)The most prominent river system within California is formed by the Sacramento River and San Joaquin River, which are fed mostly by snowmelt from the west slope of the Sierra Nevada, and respectively drain the north and south halves of the Central Valley.", "The two rivers join in the Sacramento–San Joaquin River Delta, flowing into the Pacific Ocean through San Francisco Bay.", "Many major tributaries feed into the Sacramento–San Joaquin system, including the Pit River, Feather River and Tuolumne River.The Klamath and Trinity Rivers drain a large area in far northwestern California.", "The Eel River and Salinas River each drain portions of the California coast, north and south of San Francisco Bay, respectively.", "The Mojave River is the primary watercourse in the Mojave Desert, and the Santa Ana River drains much of the Transverse Ranges as it bisects Southern California.", "The Colorado River forms the state's southeast border with Arizona.Most of California's major rivers are dammed as part of two massive water projects: the Central Valley Project, providing water for agriculture in the Central Valley, and the California State Water Project diverting water from Northern to Southern California.", "The state's coasts, rivers, and other bodies of water are regulated by the California Coastal Commission.===Regions===Map of California's regionsMap showing the division between Northern California (top white) and Southern California (bottom red)California is traditionally separated into Northern California and Southern California, divided by a straight border which runs across the state, separating the northern 48 counties from the southern 10 counties.", "Despite the persistence of the northern-southern divide, California is more precisely divided into many regions, multiple of which stretch across the northern-southern divide.", "; Major divisions* '''Northern California'''* '''Southern California'''; Regions=== Cities and towns ===The state has 482 incorporated cities and towns, of which 460 are cities and 22 are towns.", "Under California law, the terms \"city\" and \"town\" are explicitly interchangeable; the name of an incorporated municipality in the state can either be \"City of (Name)\" or \"Town of (Name)\".Sacramento became California's first incorporated city on February 27, 1850.San Jose, San Diego, and Benicia tied for California's second incorporated city, each receiving incorporation on March 27, 1850.Jurupa Valley became the state's most recent and 482nd incorporated municipality, on July 1, 2011.The majority of these cities and towns are within one of five metropolitan areas: the Los Angeles Metropolitan Area, the San Francisco Bay Area, the Riverside-San Bernardino Area, the San Diego metropolitan area, or the Sacramento metropolitan area.+ Largest metropolitan statistical areas in California CA rank U.S. rankMetropolitan statistical area2020 census2010 censusChangeCountiesLos Angeles-Long Beach-Anaheim, CA MSA Los Angeles, OrangeSan Francisco-Oakland-Hayward, CA MSA Alameda, Contra Costa, Marin, San Francisco, San MateoRiverside-San Bernardino-Ontario, CA MSA Riverside, San BernardinoSan Diego-Carlsbad, CA MSA San DiegoSacramento–Roseville–Arden-Arcade, CA MSA El Dorado, Placer, Sacramento, YoloSan Jose-Sunnyvale-Santa Clara, CA MSA San Benito, Santa ClaraFresno, CA MSA FresnoBakersfield, CA MSA KernOxnard-Thousand Oaks-Ventura, CA MSA VenturaStockton-Lodi, CA MSA San Joaquin+ Largest combined statistical areas in California CA rank U.S. rankCombined statistical area2020 census2010 censusChangeCountiesLos Angeles-Long Beach, CA Combined Statistical Area Los Angeles, Orange, Riverside, San Bernardino, VenturaSan Jose-San Francisco-Oakland, CA Combined Statistical Area Alameda, Contra Costa, Marin, Merced, Napa, San Benito, San Francisco, San Joaquin, San Mateo, Santa Clara, Santa Cruz, Solano, Sonoma, StanislausSacramento-Roseville, CA Combined Statistical Area El Dorado, Nevada, Placer, Sacramento, Sutter, Yolo, YubaFresno-Madera, CA Combined Statistical Area Fresno, Kings, MaderaRedding-Red Bluff, CA Combined Statistical Area Shasta, Tehama" ], [ "Demographics", "===Population===Nearly one out of every eight Americans lives in California.", "The United States Census Bureau reported that the population of California was 39,538,223 on April 1, 2020, a 6.13% increase since the 2010 census.", "The estimated state population in 2022 was 39.22 million.", "For over a century (1900–2020), California experienced steady population growth, adding an average of more than 300,000 people per year from 1940 onward.", "California's rate of growth began to slow by the 1990s, although it continued to experience population growth in the first two decades of the 21st century.", "The state experienced population declines in 2020 and 2021, attributable to declining birth rates, COVID-19 pandemic deaths, and less internal migration from other states to California.", "According to the U.S. Census Bureau, between 2021 and 2022, 818,000 California residents moved out of state with emigrants listing high cost of living, high taxes, and a difficult business environment as the motivation.California's population density, 2020The Greater Los Angeles Area is the second-largest metropolitan area in the United States (U.S.), while Los Angeles is the second-largest city in the U.S. Conversely, San Francisco is the most densely-populated city in California and one of the most densely populated cities in the U.S.. Also, Los Angeles County has held the title of most populous U.S. county for decades, and it alone is more populous than 42 U.S. states.", "Including Los Angeles, four of the top 20 most populous cities in the U.S. are in California: Los Angeles (2nd), San Diego (8th), San Jose (10th), and San Francisco (17th).", "The center of population of California is located four miles west-southwest of the city of Shafter, Kern County.As of 2019, California ranked second among states by life expectancy, with a life expectancy of 80.9 years.Starting in the year 2010, for the first time since the California Gold Rush, California-born residents made up the majority of the state's population.", "Along with the rest of the United States, California's immigration pattern has also shifted over the course of the late 2000s to early 2010s.", "Immigration from Latin American countries has dropped significantly with most immigrants now coming from Asia.", "In total for 2011, there were 277,304 immigrants.", "Fifty-seven percent came from Asian countries versus 22% from Latin American countries.", "Net immigration from Mexico, previously the most common country of origin for new immigrants, has dropped to zero / less than zero since more Mexican nationals are departing for their home country than immigrating.The state's population of undocumented immigrants has been shrinking in recent years, due to increased enforcement and decreased job opportunities for lower-skilled workers.", "The number of migrants arrested attempting to cross the Mexican border in the Southwest decreased from a high of 1.1million in 2005 to 367,000 in 2011.Despite these recent trends, illegal aliens constituted an estimated 7.3 percent of the state's population, the third highest percentage of any state in the country, totaling nearly 2.6million.", "In particular, illegal immigrants tended to be concentrated in Los Angeles, Monterey, San Benito, Imperial, and Napa Counties—the latter four of which have significant agricultural industries that depend on manual labor.", "More than half of illegal immigrants originate from Mexico.", "The state of California and some California cities, including Los Angeles, Oakland and San Francisco, have adopted sanctuary policies.According to HUD's 2022 Annual Homeless Assessment Report, there were an estimated 171,521 homeless people in California.===Race and ethnicity===Hispanic and Latino Californians make up the state's largest ethnic group.", "The map displays California's counties by percentage of Hispanics and Latinos in the 2020 Census:Racial and ethnic composition as of the 2020 census Race and ethnicityAloneTotal Hispanic or Latino White (non-Hispanic) Asian (non-Hispanic) African American (non-Hispanic) Native American (non-Hispanic) Pacific Islander (non-Hispanic) Other (non-Hispanic) Ethnic origins in CaliforniaAccording to the United States Census Bureau in 2018 the population self-identified as (alone or in combination): 72.1% White (including Hispanic Whites), 36.8% non-Hispanic whites, 15.3% Asian, 6.5% Black or African American, 1.6% Native American and Alaska Native, 0.5% Native Hawaiian or Pacific Islander, and 3.9% two or more races.By ethnicity, in 2018 the population was 60.7% non-Hispanic (of any race) and 39.3% Hispanic or Latino (of any race).", "Hispanics are the largest single ethnic group in California.", "Non-Hispanic whites constituted 36.8% of the state's population.", "''Californios'' are the Hispanic residents native to California, who make up the Spanish-speaking community that has existed in California since 1542, of varying Mexican American/Chicano, Criollo Spaniard, and Mestizo origin.", "California has the largest Mexican, Salvadoran and Guatemalan population., 75.1% of California's population younger than age 1 were minorities, meaning they had at least one parent who was not non-Hispanic white (white Hispanics are counted as minorities).In terms of total numbers, California has the largest population of White Americans in the United States, an estimated 22,200,000 residents.", "The state has the 5th largest population of African Americans in the United States, an estimated 2,250,000 residents.", "California's Asian American population is estimated at 4.4million, constituting a third of the nation's total.", "California's Native American population of 285,000 is the most of any state.According to estimates from 2011, California has the largest minority population in the United States by numbers, making up 60% of the state population.", "Over the past 25 years, the population of non-Hispanic whites has declined, while Hispanic and Asian populations have grown.", "Between 1970 and 2011, non-Hispanic whites declined from 80% of the state's population to 40%, while Hispanics grew from 32% in 2000 to 38% in 2011.It is currently projected that Hispanics will rise to 49% of the population by 2060, primarily due to domestic births rather than immigration.", "With the decline of immigration from Latin America, Asian Americans now constitute the fastest growing racial/ethnic group in California; this growth is primarily driven by immigration from China, India and the Philippines, respectively.Most of California's immigrant population are born in Mexico (3.9 million), the Philippines (825,200), China (768,400), India (556,500) and Vietnam (502,600).California has the largest multiracial population in the United States.", "California has the highest rate of interracial marriage.By the year 1880, the most of California's immigrants came from Ireland, China, New York, Germany and England.Mexican is the most common ancestry in California, followed by English, German and Irish.===Languages===+ '''Languages spoken in California by more than 100,000 persons''' Language Population() %English20,763,638Spanish10,434,308Chinese1,244,445Tagalog757,488Vietnamese544,046Korean356,901Arabic231,612Persian221,650Armenian211,614Hindi208,148Russian178,176Punjabi156,763Japanese135,992French126,371English serves as California's de jure and de facto official language.", "According to the 2021 American Community Survey conducted by the United States Census Bureau, 56.08% (20,763,638) of California residents age5 and older spoke only English at home, while 43.92% spoke another language at home.", "60.35% of people who speak a language other than English at home are able to speak English \"well\" or \"very well\", with this figure varying significantly across the different linguistic groups.", "Like most U.S. states (32 out of 50), California law enshrines English as its official language, and has done so since the passage of Proposition 63 by California voters in 1986.Various government agencies do, and are often required to, furnish documents in the various languages needed to reach their intended audiences.Spanish is the most commonly spoken language in California, behind English, spoken by 28.18% (10,434,308) of the population (in 2021).", "The Spanish language has been spoken in California since 1542 and is deeply intertwined with California's cultural landscape and history.", "Spanish was the official administrative language of California through the Spanish and Mexican eras, until 1848.Following the U.S. Conquest of California and the Treaty of Guadalupe-Hidalgo, the U.S. Government guaranteed the rights of Spanish speaking Californians.", "The first Constitution of California was written in both languages at the Monterey Constitutional Convention of 1849 and protected the rights of Spanish speakers to use their language in government proceedings and mandating that all government documents be published in both English and Spanish.Despite the initial recognition of Spanish by early American governments in California, the revised 1879 constitution stripped the rights of Spanish speakers and the official status of Spanish.", "The growth of the English-only movement by the mid-20th century led to the passage of 1986 California Proposition 63, which enshrined English as the only official language in California and ended Spanish language instruction in schools.", "2016 California Proposition 58 reversed the prohibition on bilingual education, though there are still many barriers to the proliferation of Spanish bilingual education, including a shortage of teachers and lack of funding.", "The government of California has since made efforts to promote Spanish language access and bilingual education, as have private educational institutions in California.", "Many businesses in California promote the usage of Spanish by their employees, to better serve both California's Hispanic population and the larger Spanish-speaking world.California has historically been one of the most linguistically diverse areas in the world, with more than 70 indigenous languages derived from 64 root languages in six language families.", "A survey conducted between 2007 and 2009 identified 23 different indigenous languages among California farmworkers.", "All of California's indigenous languages are endangered, although there are now efforts toward language revitalization.", "California has the highest concentration nationwide of Chinese, Vietnamese and Punjabi speakers.As a result of the state's increasing diversity and migration from other areas across the country and around the globe, linguists began noticing a noteworthy set of emerging characteristics of spoken American English in California since the late 20th century.", "This variety, known as California English, has a vowel shift and several other phonological processes that are different from varieties of American English used in other regions of the United States.=== Religion ===The largest religious denominations by number of adherents as a percentage of California's population in 2014 were the Catholic Church with 28 percent, Evangelical Protestants with 20 percent, and Mainline Protestants with 10 percent.", "Together, all kinds of Protestants accounted for 32 percent.", "Those unaffiliated with any religion represented 27 percent of the population.", "The breakdown of other religions is 1% Muslim, 2% Hindu and 2% Buddhist.", "This is a change from 2008, when the population identified their religion with the Catholic Church with 31 percent; Evangelical Protestants with 18 percent; and Mainline Protestants with 14 percent.", "In 2008, those unaffiliated with any religion represented 21 percent of the population.", "The breakdown of other religions in 2008 was 0.5% Muslim, 1% Hindu and 2% Buddhist.", "The ''American Jewish Year Book'' placed the total Jewish population of California at about 1,194,190 in 2006.According to the Association of Religion Data Archives (ARDA) the largest denominations by adherents in 2010 were the Catholic Church with 10,233,334; The Church of Jesus Christ of Latter-day Saints with 763,818; and the Southern Baptist Convention with 489,953.Cathedral of San Carlos Borromeo in Monterey, built 1791–94, is the oldest parish in California.|leftThe first priests to come to California were Catholic missionaries from Spain.", "Catholics founded 21 missions along the California coast, as well as the cities of Los Angeles and San Francisco.", "California continues to have a large Catholic population due to the large numbers of Mexicans and Central Americans living within its borders.", "California has twelve dioceses and two archdioceses, the Archdiocese of Los Angeles and the Archdiocese of San Francisco, the former being the largest archdiocese in the United States.A Pew Research Center survey revealed that California is somewhat less religious than the rest of the states: 62 percent of Californians say they are \"absolutely certain\" of their belief in God, while in the nation 71 percent say so.", "The survey also revealed 48 percent of Californians say religion is \"very important\", compared to 56 percent nationally." ], [ "Culture", "The Hollywood Sign in Los AngelesThe culture of California is a Western culture and has its modern roots in the culture of the United States, but also, historically, many Hispanic Californio and Mexican influences.", "As a border and coastal state, California culture has been greatly influenced by several large immigrant populations, especially those from Latin America and Asia.California has long been a subject of interest in the public mind and has often been promoted by its boosters as a kind of paradise.", "In the early 20th century, fueled by the efforts of state and local boosters, many Americans saw the Golden State as an ideal resort destination, sunny and dry all year round with easy access to the ocean and mountains.", "In the 1960s, popular music groups such as the Beach Boys promoted the image of Californians as laid-back, tanned beach-goers.The California Gold Rush of the 1850s is still seen as a symbol of California's economic style, which tends to generate technology, social, entertainment, and economic fads and booms and related busts.===Media and entertainment===Disney, headquartered in Burbank, is one of the world's largest media and entertainment companies.Hollywood and the rest of the Los Angeles area is a major global center for entertainment, with the U.S. film industry's \"Big Five\" major film studios (Columbia, Disney, Paramount, Universal, and Warner Bros.) as well as many minor film studios being based in or around the area.", "Many animation studios are also headquartered in the state.The four major American television commercial broadcast networks (ABC, CBS, NBC, and Fox) as well as other networks all have production facilities and offices in the state.", "All the four major commercial broadcast networks, plus the two major Spanish-language networks (Telemundo and Univision) each have at least three owned-and-operated TV stations in California, including at least one in Los Angeles and at least one in San Francisco.Twitter, headquartered in San Francisco, is one of the largest social media networks in the world.The California State Fair is held annually during the summer at Cal Expo in northeastern Sacramento.One of the oldest radio stations in the United States still in existence, KCBS (AM) in the San Francisco Bay Area, was founded in 1909.Universal Music Group, one of the \"Big Four\" record labels, is based in Santa Monica, while Warner Records is based in Los Angeles.", "Many independent record labels, such as Mind of a Genius Records, are also headquartered in the state.", "California is also the birthplace of several international music genres, including the Bakersfield sound, Bay Area thrash metal, alternative rock, g-funk, nu metal, glam metal, thrash metal, psychedelic rock, stoner rock, punk rock, hardcore punk, metalcore, pop punk, surf music, third wave ska, west coast hip hop, west coast jazz, jazz rap, and many other genres.", "Other genres such as pop rock, indie rock, hard rock, hip hop, pop, rock, rockabilly, country, heavy metal, grunge, new wave and disco were popularized in the state.", "In addition, many British bands, such as Led Zeppelin, Deep Purple, Black Sabbath, and the Rolling Stones settled in the state after becoming internationally famous.As the home of Silicon Valley, the Bay Area is the headquarters of several prominent internet media, social media, and other technology companies.", "Three of the \"Big Five\" technology companies (Apple, Meta, and Google) are based in the area as well as other services such as Netflix, Pandora Radio, Twitter, Yahoo!, and YouTube.", "Other prominent companies that are headquartered here include HP inc. and Intel.", "Microsoft and Amazon also have offices in the area.California, particularly Southern California, is considered the birthplace of modern car culture.Several fast food, fast casual, and casual dining chains were also founded California, including some that have since expanded internationally like California Pizza Kitchen, Denny's, IHOP, McDonald's, Panda Express, and Taco Bell.===Sports===Pebble Beach Golf Links, one of the best ranked golf courses in the worldThe Grand Prix of Long Beach is the longest running major street race in North America.California has nineteen major professional sports league franchises, far more than any other state.", "The San Francisco Bay Area has six major league teams spread in its three major cities: San Francisco, San Jose, and Oakland, while the Greater Los Angeles Area is home to ten major league franchises.", "San Diego and Sacramento each have one major league team.", "The NFL Super Bowl has been hosted in California 12 times at five different stadiums: Los Angeles Memorial Coliseum, the Rose Bowl, Stanford Stadium, Levi's Stadium, and San Diego's Qualcomm Stadium.", "A thirteenth, Super Bowl LVI, was held at SoFi Stadium in Inglewood on February 13, 2022.California has long had many respected collegiate sports programs.", "California is home to the oldest college bowl game, the annual Rose Bowl, among others.The NFL has three teams in the state: the Los Angeles Rams, Los Angeles Chargers, and San Francisco 49ers.MLB has five teams in the state: the San Francisco Giants, Oakland Athletics, Los Angeles Dodgers, Los Angeles Angels, and San Diego Padres.The NBA has four teams in the state: the Golden State Warriors, Los Angeles Clippers, Los Angeles Lakers, and Sacramento Kings.", "Additionally, the WNBA also has one team in the state: the Los Angeles Sparks.The NHL has three teams in the state: the Anaheim Ducks, Los Angeles Kings, and San Jose Sharks.MLS has three teams in the state: the Los Angeles Galaxy, San Jose Earthquakes, and Los Angeles Football Club.MLR has one team in the state: the San Diego Legion.California is the only U.S. state to have hosted both the Summer and Winter Olympics.", "The 1932 and 1984 summer games were held in Los Angeles.", "Squaw Valley Ski Resort (now Palisades Tahoe) in the Lake Tahoe region hosted the 1960 Winter Olympics.", "Los Angeles will host the 2028 Summer Olympics, marking the fourth time that California will have hosted the Olympic Games.", "Multiple games during the 1994 FIFA World Cup took place in California, with the Rose Bowl hosting eight matches (including the final), while Stanford Stadium hosted six matches.In addition to the Olympic games, California also hosts the California State Games.Many sports, such as surfing, snowboarding, and skateboarding, were invented in California, while others like volleyball, beach soccer, and skiing were popularized in the state.Other sports that are big in the state include golf, rodeo, tennis, mountain climbing, marathon running, horse racing, bowling, mixed martial arts, boxing, and motorsports, especially NASCAR and Formula One.Los Angeles Memorial Coliseum hosted the Summer Olympics in 1932 and 1984, and will also host in 2028.Team Sport LeagueLos Angeles RamsAmerican footballNational Football League (NFL)Los Angeles ChargersAmerican footballNational Football LeagueSan Francisco 49ersAmerican footballNational Football LeagueLos Angeles DodgersBaseballMajor League Baseball (MLB)Los Angeles AngelsBaseballMajor League BaseballOakland AthleticsBaseballMajor League BaseballSan Diego PadresBaseballMajor League BaseballSan Francisco GiantsBaseballMajor League BaseballGolden State WarriorsBasketballNational Basketball Association (NBA)Los Angeles ClippersBasketballNational Basketball AssociationLos Angeles LakersBasketballNational Basketball AssociationSacramento KingsBasketballNational Basketball AssociationLos Angeles SparksBasketballWomen's National Basketball Association (WNBA)Anaheim DucksIce hockeyNational Hockey League (NHL)Los Angeles KingsIce hockeyNational Hockey LeagueSan Jose SharksIce hockeyNational Hockey LeagueLos Angeles GalaxySoccerMajor League Soccer (MLS)San Jose EarthquakesSoccerMajor League SoccerLos Angeles Football ClubSoccerMajor League SoccerAngel City FCSoccerNational Women's Soccer League (NWSL)San Diego Wave FCSoccerNational Women's Soccer LeagueSan Diego LegionRugby unionMajor League Rugby" ], [ "Education", "Santa Barbara High School, one of the oldest high schools in continuous use in Southern CaliforniaCalifornia has the most school students in the country, with over 6.2 million in the 2005–06 school year, giving California more students in school than 36 states have in total population and one of the highest projected enrollments in the country.Public secondary education consists of high schools that teach elective courses in trades, languages, and liberal arts with tracks for gifted, college-bound and industrial arts students.", "California's public educational system is supported by a unique constitutional amendment that requires a minimum annual funding level for grades K–12 and community colleges that grows with the economy and student enrollment figures.In 2016, California's K–12 public school per-pupil spending was ranked 22nd in the nation ($11,500 per student vs. $11,800 for the U.S. average).For 2012, California's K–12 public schools ranked 48th in the number of employees per student, at 0.102 (the U.S. average was 0.137), while paying the 7th most per employee, $49,000 (the U.S. average was $39,000).A 2007 study concluded that California's public school system was \"broken\" in that it suffered from overregulation.===Higher education===UC Berkeley is the oldest campus of the University of California, and the state's flagship public university.Stanford University is a private university that is one of the top-ranked universities in the world.California public postsecondary education is organized into three separate systems:* The state's public research university system is the University of California (UC).", "As of fall 2011, the University of California had a combined student body of 234,464 students.", "There are ten UC campuses; nine are general campuses offering both undergraduate and graduate programs which culminate in the award of bachelor's degrees, master's degrees, and doctorates; there is one specialized campus, UC San Francisco, which is entirely dedicated to graduate education in health care, and is home to the UCSF Medical Center, the highest-ranked hospital in California.", "The system was originally intended to accept the top one-eighth of California high school students, but several of the campuses have become even more selective.", "The UC system historically held exclusive authority to award the doctorate, but this has since changed and CSU now has limited statutory authorization to award a handful of types of doctoral degrees independently of UC.", "* The California State University (CSU) system has almost 430,000 students.", "The CSU (which takes the definite article in its abbreviated form, while UC does not) was originally intended to accept the top one-third of California high school students, but several of the campuses have become much more selective.", "The CSU was originally authorized to award only bachelor's and master's degrees, and could award the doctorate only as part of joint programs with UC or private universities.", "Since then, CSU has been granted the authority to independently award several doctoral degrees (in specific academic fields that do not intrude upon UC's traditional jurisdiction).", "* The California Community Colleges system provides lower-division coursework culminating in the associate degree, as well as basic skills and workforce training culminating in various kinds of certificates.", "(Fifteen California community colleges now award four-year bachelor's degrees in disciplines which are in high demand in their geographical area.)", "It is the largest network of higher education in the U.S., composed of 112 colleges serving a student population of over 2.6million.California is also home to notable private universities such as Stanford University, the California Institute of Technology (Caltech), the University of Southern California, the Claremont Colleges, Santa Clara University, Loyola Marymount University, the University of San Diego, the University of San Francisco, Chapman University, Pepperdine University, Occidental College, and University of the Pacific, among numerous other private colleges and universities, including many religious and special-purpose institutions.", "California has a particularly high density of arts colleges, including the California College of the Arts, California Institute of the Arts, San Francisco Art Institute, Art Center College of Design, and Academy of Art University, among others." ], [ "Economy", "Silicon Valley is the largest tech hub in the world and home to Big Tech companies like Apple, Alphabet, Meta, Intel, Netflix, Inc., Uber, Nvidia, HP, X Corp and many more.California's economy ranks among the largest in the world.", ", the gross state product (GSP) was $3.6trillion ($92,190 per capita), the largest in the United States.", "California is responsible for one seventh of the nation's gross domestic product (GDP).", ", California's nominal GDP is larger than all but four countries (the United States, China, Japan, and Germany).", "In terms of purchasing power parity (PPP), it is larger than all but eight countries (the United States, China, India, Japan, Germany, Russia, Brazil, and Indonesia).", "California's economy is larger than Africa and Australia and is almost as large as South America.", "The state recorded total, non-farm employment of 16,677,800 among 966,224 employer establishments.The combined Port of Los Angeles-Port of Long Beach is the largest port in the U.S. by import volume and one of the busiest ports in the world.As the largest and second-largest U.S. ports respectively, the Port of Los Angeles and the Port of Long Beach in Southern California collectively play a pivotal role in the global supply chain, together hauling in about 40% of all imports to the United States by TEU volume.", "The Port of Oakland and Port of Hueneme are the 10th and 26th largest seaports in the U.S., respectively, by number of TEUs handled.The five largest sectors of employment in California are trade, transportation, and utilities; government; professional and business services; education and health services; and leisure and hospitality.", "In output, the five largest sectors are financial services, followed by trade, transportation, and utilities; education and health services; government; and manufacturing.", "California has an unemployment rate of 3.9% .California's economy is dependent on trade and international related commerce accounts for about one-quarter of the state's economy.", "In 2008, California exported $144billion worth of goods, up from $134billion in 2007 and $127billion in 2006.Computers and electronic products are California's top export, accounting for 42 percent of all the state's exports in 2008.=== Agriculture ===California vineyards in Wine Country.", "The agricultural industry in California is the largest in the U.S.Agriculture is an important sector in California's economy.", "According to the USDA in 2011, the three largest California agricultural products by value were milk and cream, shelled almonds, and grapes.", "Farming-related sales more than quadrupled over the past three decades, from $7.3billion in 1974 to nearly $31billion in 2004.This increase has occurred despite a 15 percent decline in acreage devoted to farming during the period, and water supply suffering from chronic instability.", "Factors contributing to the growth in sales-per-acre include more intensive use of active farmlands and technological improvements in crop production.", "In 2008, California's 81,500 farms and ranches generated $36.2billion products revenue.", "In 2011, that number grew to $43.5billion products revenue.", "The agriculture sector accounts for two percent of the state's GDP and employs around three percent of its total workforce.=== Income ===California is the most visited state in the country.", "Disneyland in Anaheim is a major tourist destination, with 16.9 million annual visits in 2022.Per capita GDP in 2007 was $38,956, ranking eleventh in the nation.", "Per capita income varies widely by geographic region and profession.", "The Central Valley is the most impoverished, with migrant farm workers making less than minimum wage.", "According to a 2005 report by the Congressional Research Service, the San Joaquin Valley was characterized as one of the most economically depressed regions in the United States, on par with the region of Appalachia.Using the supplemental poverty measure, California has a poverty rate of 23.5%, the highest of any state in the country.", "However, using the official measure the poverty rate was only 13.3% as of 2017.Many coastal cities include some of the wealthiest per-capita areas in the United States.", "The high-technology sectors in Northern California, specifically Silicon Valley, in Santa Clara and San Mateo counties, have emerged from the economic downturn caused by the dot-com bust.In 2019, there were 1,042,027 millionaire households in the state, more than any other state in the nation.", "In 2010, California residents were ranked first among the states with the best average credit score of 754.File:USA-World Nominal GDP.PNG|If California was an independent country, its gross domestic product (nominal) would rank fifth in the world (2022).File:California counties by GDP 2021.png|California counties by GDP (2021)===State finances===California economic regionsState spending increased from $56billion in 1998 to $127billion in 2011.California has the third highest per capita spending on welfare among the states, as well as the highest spending on welfare at $6.67billion.", "In January 2011, California's total debt was at least $265billion.", "On June 27, 2013, Governor Jerry Brown signed a balanced budget (no deficit) for the state, its first in decades; however, the state's debt remains at $132billion.With the passage of Proposition 30 in 2012 and Proposition 55 in 2016, California now levies a 13.3% maximum marginal income tax rate with ten tax brackets, ranging from 1% at the bottom tax bracket of $0 annual individual income to 13.3% for annual individual income over $1,000,000 (though the top brackets are only temporary until Proposition 55 expires at the end of 2030).", "While Proposition 30 also enacted a minimum state sales tax of 7.5%, this sales tax increase was not extended by Proposition 55 and reverted to a previous minimum state sales tax rate of 7.25% in 2017.Local governments can and do levy additional sales taxes in addition to this minimum rate.All real property is taxable annually; the ad valorem tax is based on the property's fair market value at the time of purchase or the value of new construction.", "Property tax increases are capped at 2% annually or the rate of inflation (whichever is lower), per Proposition 13." ], [ "Infrastructure", "===Energy===Moss Landing Power Plant, located on the coast of Monterey BayBecause it is the most populous state in the United States, California is one of the country's largest users of energy.", "The state has extensive hydro-electric energy generation facilities, however, moving water is the single largest energy use in the state.", "Also, due to high energy rates, conservation mandates, mild weather in the largest population centers and strong environmental movement, its ''per capita'' energy use is one of the smallest of any state in the United States.", "Due to the high electricity demand, California imports more electricity than any other state, primarily hydroelectric power from states in the Pacific Northwest (via Path 15 and Path 66) and coal- and natural gas-fired production from the desert Southwest via Path 46.The state's crude oil and natural gas deposits are located in the Central Valley and along the coast, including the large Midway-Sunset Oil Field.", "Natural gas-fired power plants typically account for more than one-half of state electricity generation.Ivanpah Solar Power Facility, located in the Mojave DesertAs a result of the state's strong environmental movement, California has some of the most aggressive renewable energy goals in the United States.", "Senate Bill SB 1020 (the Clean Energy, Jobs and Affordability Act of 2022) commits the state to running its operations on clean, renewable energy resources by 2035, and SB 1203 also requires the state to achieve net-zero operations for all agencies.", "Currently, several solar power plants such as the Solar Energy Generating Systems facility are located in the Mojave Desert.", "California's wind farms include Altamont Pass, San Gorgonio Pass, and Tehachapi Pass.", "The Tehachapi area is also where the Tehachapi Energy Storage Project is located.", "Several dams across the state provide hydro-electric power.", "It would be possible to convert the total supply to 100% renewable energy, including heating, cooling and mobility, by 2050.California has one major nuclear power plant (Diablo Canyon) in operation.", "The San Onofre nuclear plant was shut down in 2013.More than 1,700tons of radioactive waste are stored at San Onofre, and sit on the coast where there is a record of past tsunamis.", "Voters banned the approval of new nuclear power plants since the late 1970s because of concerns over radioactive waste disposal.", "In addition, several cities such as Oakland, Berkeley and Davis have declared themselves as nuclear-free zones.===Transportation===The Golden Gate Bridge in the San Francisco Bay Area, is one of the most famous bridges in the world.====Highways====California's vast terrain is connected by an extensive system of controlled-access highways ('freeways'), limited-access roads ('expressways'), and highways.", "California is known for its car culture, giving California's cities a reputation for severe traffic congestion.", "Construction and maintenance of state roads and statewide transportation planning are primarily the responsibility of the California Department of Transportation, nicknamed \"Caltrans\".", "The rapidly growing population of the state is straining all of its transportation networks, and California has some of the worst roads in the United States.", "The Reason Foundation's 19th Annual Report on the Performance of State Highway Systems ranked California's highways the third-worst of any state, with Alaska second, and Rhode Island first.San Francisco Bay Ferry is a public water taxi system in the Bay Area.", "The state has been a pioneer in road construction.", "One of the state's more visible landmarks, the Golden Gate Bridge, was the longest suspension bridge main span in the world at between 1937 (when it opened) and 1964.With its orange paint and panoramic views of the bay, this highway bridge is a popular tourist attraction and also accommodates pedestrians and bicyclists.", "The San Francisco–Oakland Bay Bridge (often abbreviated the \"Bay Bridge\"), completed in 1936, transports about 280,000 vehicles per day on two-decks.", "Its two sections meet at Yerba Buena Island through the world's largest diameter transportation bore tunnel, at wide by high.", "The Arroyo Seco Parkway, connecting Los Angeles and Pasadena, opened in 1940 as the first freeway in the Western United States.", "It was later extended south to the Four Level Interchange in downtown Los Angeles, regarded as the first stack interchange ever built.The California Highway Patrol is the largest statewide police agency in the United States in employment with more than 10,000 employees.", "They are responsible for providing any police-sanctioned service to anyone on California's state-maintained highways and on state property.By the end of 2021, 30,610,058 people in California held a California Department of Motor Vehicles-issued driver's licenses or state identification card, and there were 36,229,205 registered vehicles, including 25,643,076 automobiles, 853,368 motorcycles, 8,981,787 trucks and trailers, and 121,716 miscellaneous vehicles (including historical vehicles and farm equipment).====Air travel====Los Angeles Intl.", "Airport (LAX) is the 4th busiest airport in the world.Los Angeles International Airport (LAX), the 4th busiest airport in the world in 2018, and San Francisco International Airport (SFO), the 25th busiest airport in the world in 2018, are major hubs for trans-Pacific and transcontinental traffic.", "There are about a dozen important commercial airports and many more general aviation airports throughout the state.====Railroads====Amtrak California's ''Pacific Surfliner'' in San Clemente, on the Orange CoastInter-city rail travel is provided by Amtrak California; the three routes, the ''Capitol Corridor'', ''Pacific Surfliner'', and ''San Joaquin'', are funded by Caltrans.", "These services are the busiest intercity rail lines in the United States outside the Northeast Corridor and ridership is continuing to set records.", "The routes are becoming increasingly popular over flying, especially on the LAX-SFO route.", "Integrated subway and light rail networks are found in Los Angeles (Los Angeles Metro Rail) and San Francisco (Muni Metro).", "Light rail systems are also found in San Jose (VTA light rail), San Diego (San Diego Trolley), Sacramento (Sacramento RT Light Rail), and Northern San Diego County (Sprinter).", "Furthermore, commuter rail networks serve the San Francisco Bay Area (Altamont Corridor Express, Bay Area Rapid Transit, Caltrain, Sonoma–Marin Area Rail Transit), Greater Los Angeles (Metrolink), and San Diego County (Coaster).The California High-Speed Rail Authority was authorized in 1996 by the state legislature to plan a California High-Speed Rail system to put before the voters.", "The plan they devised, 2008 California Proposition 1A, connecting all the major population centers in the state, was approved by the voters at the November 2008 general election.", "The first phase of construction was begun in 2015, and the first segment long, is planned to be put into operation by the end of 2030.Planning and work on the rest of the system is continuing, with funding for completing it is an ongoing issue.", "California's 2023 integrated passenger rail master plan includes a high speed rail system.====Busses====Nearly all counties operate bus lines, and many cities operate their own city bus lines as well.", "Intercity bus travel is provided by Greyhound, Megabus, and Amtrak Thruway.===Water===Lake Shasta, in the Shasta Cascade region, is California's largest reservoir.California's interconnected water system is the world's largest, managing over of water per year, centered on six main systems of aqueducts and infrastructure projects.", "Water use and conservation in California is a politically divisive issue, as the state experiences periodic droughts and has to balance the demands of its large agricultural and urban sectors, especially in the arid southern portion of the state.", "The state's widespread redistribution of water also invites the frequent scorn of environmentalists.The California Water Wars, a conflict between Los Angeles and the Owens Valley over water rights, is one of the most well-known examples of the struggle to secure adequate water supplies.", "Former California Governor Arnold Schwarzenegger said: \"We've been in crisis for quite some time because we're now 38million people and not anymore 18million people like we were in the late 60s.", "So it developed into a battle between environmentalists and farmers and between the south and the north and between rural and urban.", "And everyone has been fighting for the last four decades about water.\"" ], [ "Government and politics", "The California Capitol in Sacramento, seat of the California government, hosts the California Legislature and the Governor of California.===State government===The capital city of California is Sacramento.The state is organized into three branches of government—the executive branch consisting of the governor and the other independently elected constitutional officers; the legislative branch consisting of the Assembly and Senate; and the judicial branch consisting of the Supreme Court of California and lower courts.", "The state also allows ballot propositions: direct participation of the electorate by initiative, referendum, recall, and ratification.", "Before the passage of Proposition 14 in 2010, California allowed each political party to choose whether to have a closed primary or a primary where only party members and independents vote.", "After June 8, 2010, when Proposition 14 was approved, excepting only the United States president and county central committee offices, all candidates in the primary elections are listed on the ballot with their preferred party affiliation, but they are not the official nominee of that party.", "At the primary election, the two candidates with the top votes will advance to the general election regardless of party affiliation.", "If at a special primary election, one candidate receives more than 50% of all the votes cast, they are elected to fill the vacancy and no special general election will be held.====Executive branch====Stanford Mansion is the official reception center for the California government and one of the workplaces of the Governor of California.The California executive branch consists of the governor and seven other elected constitutional officers: lieutenant governor, attorney general, secretary of state, state controller, state treasurer, insurance commissioner, and state superintendent of public instruction.", "They serve four-year terms and may be re-elected only once.The many California state agencies that are under the governor's cabinet are grouped together to form cabinet-level entities that are referred to by government officials as \"superagencies\".", "Those departments that are directly under the other independently elected officers work separately from these superagencies.====Legislative branch====The California State Legislature consists of a 40-member Senate and 80-member Assembly.", "Senators serve four-year terms and Assembly members two.", "Members of the Assembly are subject to term limits of six terms, and members of the Senate are subject to term limits of three terms.====Judicial branch====The Supreme Court of California is headquartered at the Earl Warren Building (shown) in San Francisco, but also meets in Sacramento and Los Angeles.California's legal system is explicitly based upon English common law but carries many features from Spanish civil law, such as community property.", "California's prison population grew from 25,000 in 1980 to over 170,000 in 2007.Capital punishment is a legal form of punishment and the state has the largest \"Death Row\" population in the country (though Oklahoma and Texas are far more active in carrying out executions).", "California has performed 13 executions since 1976, with the last being in 2006.California's judiciary system is the largest in the United States with a total of 1,600 judges (the federal system has only about 840).", "At the apex is the seven-member Supreme Court of California, while the California Courts of Appeal serve as the primary appellate courts and the California Superior Courts serve as the primary trial courts.", "Justices of the Supreme Court and Courts of Appeal are appointed by the governor, but are subject to retention by the electorate every 12 years.The administration of the state's court system is controlled by the Judicial Council, composed of the chief justice of the California Supreme Court, 14 judicial officers, four representatives from the State Bar of California, and one member from each house of the state legislature.In fiscal year 2020–2021, the state judiciary's 2,000 judicial officers and 18,000 judicial branch employees processed approximately 4.4 million cases.===Local government===San Francisco City Hall is the seat of government of the consolidated City and County of San Francisco.California has an extensive system of local government that manages public functions throughout the state.", "Like most states, California is divided into counties, of which there are 58 (including San Francisco) covering the entire state.", "Most urbanized areas are incorporated as cities.", "School districts, which are independent of cities and counties, handle public education.", "Many other functions, such as fire protection and water supply, especially in unincorporated areas, are handled by special districts.====Counties====California is divided into 58 counties.", "Per Article 11, Section 1, of the Constitution of California, they are the legal subdivisions of the state.", "The county government provides countywide services such as law enforcement, jails, elections and voter registration, vital records, property assessment and records, tax collection, public health, health care, social services, libraries, flood control, fire protection, animal control, agricultural regulations, building inspections, ambulance services, and education departments in charge of maintaining statewide standards.", "In addition, the county serves as the local government for all unincorporated areas.", "Each county is governed by an elected board of supervisors.====City and town governments====Los Angeles City Hall, seat of the Government of Los AngelesIncorporated cities and towns in California are either charter or general-law municipalities.", "General-law municipalities owe their existence to state law and are consequently governed by it; charter municipalities are governed by their own city or town charters.", "Municipalities incorporated in the 19th century tend to be charter municipalities.", "All ten of the state's most populous cities are charter cities.", "Most small cities have a council–manager form of government, where the elected city council appoints a city manager to supervise the operations of the city.", "Some larger cities have a directly elected mayor who oversees the city government.", "In many council-manager cities, the city council selects one of its members as a mayor, sometimes rotating through the council membership—but this type of mayoral position is primarily ceremonial.", "The Government of San Francisco is the only consolidated city-county in California, where both the city and county governments have been merged into one unified jurisdiction.====School districts and special districts====Los Angeles Unified School District is the second largest school district in the United States by enrollment.About 1,102 school districts, independent of cities and counties, handle California's public education.", "California school districts may be organized as elementary districts, high school districts, unified school districts combining elementary and high school grades, or community college districts.There are about 3,400 special districts in California.", "A special district, defined by California Government Code § 16271(d) as \"any agency of the state for the local performance of governmental or proprietary functions within limited boundaries\", provides a limited range of services within a defined geographic area.", "The geographic area of a special district can spread across multiple cities or counties, or could consist of only a portion of one.", "Most of California's special districts are ''single-purpose districts'', and provide one service.===Federal representation===California Congressional Delegation in 2020The state of California sends 52 members to the House of Representatives, the nation's largest congressional state delegation.", "Consequently, California also has the largest number of electoral votes in national presidential elections, with 54.The former speaker of the House of Representatives is the representative of California's 20th district, Kevin McCarthy.California is represented in the United States Senate by Alex Padilla, a native and former secretary of state of California, and Laphonza Butler, a labor union official who was appointed to the Senate by Governor Gavin Newson to complete the term of Dianne Feinstein, who died on the 29th of September, 2023.Former U.S. senator Kamala Harris, a native, former district attorney from San Francisco, former attorney general of California, resigned on January 18, 2021, to assume her role as the current Vice President of the United States.", "In the 1992 U.S. Senate election, California became the first state to elect a Senate delegation entirely composed of women, due to the victories of Feinstein and Barbara Boxer.", "Following the Vice President, Gov.", "Newsom appointed Secretary of State Alex Padilla to finish the rest of Harris's term which ended in 2022.Padilla successfully ran for a full term that same year.", "Padilla was sworn in on January 20, 2021, the same day as the inauguration of Joe Biden as well as Harris.===Armed forces===NAS North Island at Naval Base Coronado in San DiegoIn California, , the U.S. Department of Defense had a total of 117,806 active duty servicemembers of which 88,370 were Sailors or Marines, 18,339 were Airmen, and 11,097 were Soldiers, with 61,365 Department of Defense civilian employees.", "Additionally, there were a total of 57,792 Reservists and Guardsman in California.In 2010, Los Angeles County was the largest origin of military recruits in the United States by county, with 1,437 individuals enlisting in the military.", "However, , Californians were relatively under-represented in the military as a proportion to its population.In 2000, California, had 2,569,340 veterans of United States military service: 504,010 served in World War II, 301,034 in the Korean War, 754,682 during the Vietnam War, and 278,003 during 1990–2000 (including the Persian Gulf War).", ", there were 1,942,775 veterans living in California, of which 1,457,875 served during a period of armed conflict, and just over four thousand served before World WarII (the largest population of this group of any state).California's military forces consist of the Army and Air National Guard, the naval and state military reserve (militia), and the California Cadet Corps.On August 5, 1950, a nuclear-capable United States Air Force Boeing B-29 Superfortress bomber carrying a nuclear bomb crashed shortly after takeoff from Fairfield-Suisun Air Force Base.", "Brigadier General Robert F. Travis, command pilot of the bomber, was among the dead.===Ideology===+California registered voters Party Number of voters Percentage160pxParty registration by county(October 2022): Democratic10,283,25846.87% Republican5,232,09423.85% No Party Preference4,943,69622.53% American Independent777,1523.54% Libertarian231,4591.05% Peace and Freedom123,0370.56% Green96,2290.44%Other253,3491.16%Total21,940,274100%California has an idiosyncratic political culture compared to the rest of the country, and is sometimes regarded as a trendsetter.", "In socio-cultural mores and national politics, Californians are perceived as more liberal than other Americans, especially those who live in the inland states.", "In the 2016 United States presidential election, California had the third highest percentage of Democratic votes behind the District of Columbia and Hawaii.", "In the 2020 United States presidential election, it had the 6th highest behind the District of Columbia, Vermont, Massachusetts, Maryland, and Hawaii.", "According to the Cook Political Report, California contains five of the 15 most Democratic congressional districts in the United States.Among the political idiosyncrasies, California was the second state to recall their state governor (the first state being North Dakota in 1921), the second state to legalize abortion, and the only state to ban marriage for gay couples twice by vote (including Proposition8 in 2008).", "Voters also passed Proposition 71 in 2004 to fund stem cell research, making California the second state to legalize stem cell research after New Jersey, and Proposition 14 in 2010 to completely change the state's primary election process.", "California has also experienced disputes over water rights; and a tax revolt, culminating with the passage of Proposition 13 in 1978, limiting state property taxes.", "California voters have rejected affirmative action on multiple occasions, most recently in November 2020.The state's trend towards the Democratic Party and away from the Republican Party can be seen in state elections.", "From 1899 to 1939, California had Republican governors.", "Since 1990, California has generally elected Democratic candidates to federal, state and local offices, including current Governor Gavin Newsom; however, the state has elected Republican Governors, though many of its Republican Governors, such as Arnold Schwarzenegger, tend to be considered moderate Republicans and more centrist than the national party.Anti-war protesters and pro-military counterprotesters in Berkeley (2008)Several political movements have advocated for California independence.", "The California National Party and the California Freedom Coalition both advocate for California independence along the lines of progressivism and civic nationalism.", "The Yes California movement attempted to organize an independence referendum via ballot initiative for 2019, which was then postponed.The Democrats also now hold a supermajority in both houses of the state legislature.", "There are 62 Democrats and 18 Republicans in the Assembly; and 32 Democrats and 8 Republicans in the Senate.The trend towards the Democratic Party is most obvious in presidential elections.", "From 1952 through 1988, California was a Republican leaning state, with the party carrying the state's electoral votes in nine of ten elections, with 1964 as the exception.", "Southern California Republicans Richard Nixon and Ronald Reagan were both elected twice as the 37th and 40th U.S. Presidents, respectively.", "However, Democrats have won all of California's electoral votes for the last eight elections, starting in 1992.In the United States House, the Democrats held a 34–19 edge in the CA delegation of the 110th United States Congress in 2007.As the result of gerrymandering, the districts in California were usually dominated by one or the other party, and few districts were considered competitive.", "In 2008, Californians passed Proposition 20 to empower a 14-member independent citizen commission to redraw districts for both local politicians and Congress.", "After the 2012 elections, when the new system took effect, Democrats gained four seats and held a 38–15 majority in the delegation.", "Following the 2018 midterm House elections, Democrats won 46 out of 53 congressional house seats in California, leaving Republicans with seven.Occupy Los Angeles movement (2011)In general, Democratic strength is centered in the populous coastal regions of the Los Angeles metropolitan area and the San Francisco Bay Area.", "Republican strength is still greatest in eastern parts of the state.", "Orange County had remained largely Republican until the 2016 and 2018 elections, in which a majority of the county's votes were cast for Democratic candidates.", "One study ranked Berkeley, Oakland, Inglewood and San Francisco in the top 20 most liberal American cities; and Bakersfield, Orange, Escondido, Garden Grove, and Simi Valley in the top 20 most conservative cities.In October 2022, out of the 26,876,800 people eligible to vote, 21,940,274 people were registered to vote.", "Of the people registered, the three largest registered groups were Democrats (10,283,258), Republicans (5,232,094), and No Party Preference (4,943,696).", "Los Angeles County had the largest number of registered Democrats (2,996,565) and Republicans (958,851) of any county in the state.California retains the death penalty, though it has not been used since 2006.There is currently a gubernatorial hold on executions.", "Authorized methods of execution include the gas chamber.=== Twinned regions ===California has region twinning arrangements with:* Catalonia, autonomous community of Spain* Alberta, province of Canada* Jeju Province of South Korea* Guangdong, province of China" ], [ "See also", "* Index of California-related articles* Outline of California* List of people from California" ], [ "Notes" ], [ "References", "===Citations======Works cited===* * *" ], [ "Further reading", "* * * * Matthews, Glenna.", "''The Golden State in the Civil War: Thomas Starr King, the Republican Party, and the Birth of Modern California''.", "New York: Cambridge University Press, 2012.", "* *" ], [ "External links", "* State of California* California State Guide, from the Library of Congress* * data.ca.gov: open data portal from California state agencies* California State Facts from USDA* California Drought: Farm and Food Impacts from USDA, Economic Research Service* * 1973 documentary featuring aerial views of the California coastline from Mt.", "Shasta to Los Angeles* Early City Views (Los Angeles)" ] ]

[ [ "Columbia River" ], [ "Introduction", "The '''Columbia River''' (Upper Chinook: '''' or ''''; Sahaptin: ''Nch’i-Wàna'' or ''Nchi wana''; Sinixt dialect'' '') is the largest river in the Pacific Northwest region of North America.", "The river forms in the Rocky Mountains of British Columbia, Canada.", "It flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state of Oregon before emptying into the Pacific Ocean.", "The river is long, and its largest tributary is the Snake River.", "Its drainage basin is roughly the size of France and extends into seven states of the United States and one Canadian province.", "The fourth-largest river in the United States by volume, the Columbia has the greatest flow of any river entering the Pacific outside of Asia, and the 36th greatest discharge of any river in the world.The Columbia and its tributaries have been central to the region's culture and economy for thousands of years.", "They have been used for transportation since ancient times, linking the region's many cultural groups.", "The river system hosts many species of anadromous fish, which migrate between freshwater habitats and the saline waters of the Pacific Ocean.", "These fish—especially the salmon species—provided the core subsistence for native peoples.The first documented European discovery of the Columbia River occurred when Bruno de Heceta sighted the river's mouth in 1775.On May 11, 1792, a private American ship, Columbia Rediviva, under Captain Robert Gray from Boston became the first non-indigenous vessel to enter the river.", "Later in 1792, William Robert Broughton of the British Royal Navy commanding HMS ''Chatham'' as part of the Vancouver Expedition, navigated past the Oregon Coast Range and 100 miles upriver to what is now Vancouver, Washington.", "In the following decades, fur-trading companies used the Columbia as a key transportation route.", "Overland explorers entered the Willamette Valley through the scenic, but treacherous Columbia River Gorge, and pioneers began to settle the valley in increasing numbers.", "Steamships along the river linked communities and facilitated trade; the arrival of railroads in the late 19th century, many running along the river, supplemented these links.Since the late 19th century, public and private sectors have extensively developed the river.", "To aid ship and barge navigation, locks have been built along the lower Columbia and its tributaries, and dredging has opened, maintained, and enlarged shipping channels.", "Since the early 20th century, dams have been built across the river for power generation, navigation, irrigation, and flood control.", "The 14 hydroelectric dams on the Columbia's main stem and many more on its tributaries produce more than 44 percent of total U.S. hydroelectric generation.", "Production of nuclear power has taken place at two sites along the river.", "Plutonium for nuclear weapons was produced for decades at the Hanford Site, which is now the most contaminated nuclear site in the United States.", "These developments have greatly altered river environments in the watershed, mainly through industrial pollution and barriers to fish migration." ], [ "Course", "The Columbia begins its journey in the southern Rocky Mountain Trench in British Columbia (BC).", "Columbia Lake above sea level and the adjoining Columbia Wetlands form the river's headwaters.", "The trench is a broad, deep, and long glacial valley between the Canadian Rockies and the Columbia Mountains in BC.", "For its first , the Columbia flows northwest along the trench through Windermere Lake and the town of Invermere, a region known in BC as the Columbia Valley, then northwest to Golden and into Kinbasket Lake.", "Rounding the northern end of the Selkirk Mountains, the river turns sharply south through a region known as the Big Bend Country, passing through Revelstoke Lake and the Arrow Lakes.", "Revelstoke, the Big Bend, and the Columbia Valley combined are referred to in BC parlance as the Columbia Country.", "Below the Arrow Lakes, the Columbia passes the cities of Castlegar, located at the Columbia's confluence with the Kootenay River, and Trail, two major population centers of the West Kootenay region.", "The Pend Oreille River joins the Columbia about north of the United States–Canada border.alt=Modified satellite view of the Columbia River watershed showing the course of the river in red from Columbia Lake in British Columbia, Canada, to Astoria, Oregon, in the United States.", "The maps show that the river, although flowing on average in a southwesterly direction from source to mouth, changes direction sharply from northwest to south at Big Bend in Canada, from south to west near Grand Coulee Dam in Washington, from west to south near Wenatchee, Washington, and from south to west near the Tri-Cities area in Washington.|Course of the Columbia RiverThe Columbia enters eastern Washington flowing south and turning to the west at the Spokane River confluence.", "It marks the southern and eastern borders of the Colville Indian Reservation and the western border of the Spokane Indian Reservation.", "The river turns south after the Okanogan River confluence, then southeasterly near the confluence with the Wenatchee River in central Washington.", "This C-shaped segment of the river is also known as the \"Big Bend\".", "During the Missoula Floods 1015,000 years ago, much of the floodwater took a more direct route south, forming the ancient river bed known as the Grand Coulee.", "After the floods, the river found its present course, and the Grand Coulee was left dry.", "The construction of the Grand Coulee Dam in the mid-20th century impounded the river, forming Lake Roosevelt, from which water was pumped into the dry coulee, forming the reservoir of Banks Lake.The river flows past The Gorge Amphitheatre, a prominent concert venue in the Northwest, then through Priest Rapids Dam, and then through the Hanford Nuclear Reservation.", "Entirely within the reservation is Hanford Reach, the only U.S. stretch of the river that is completely free-flowing, unimpeded by dams, and not a tidal estuary.", "The Snake River and Yakima River join the Columbia in the Tri-Cities population center.", "The Columbia makes a sharp bend to the west at the Washington–Oregon border.", "The river defines that border for the final of its journey.The Columbia River Gorge facing east toward Beacon RockThe Deschutes River joins the Columbia near The Dalles.", "Between The Dalles and Portland, the river cuts through the Cascade Range, forming the dramatic Columbia River Gorge.", "No other rivers except for the Klamath and Pit River completely breach the Cascadesthe other rivers that flow through the range also originate in or very near the mountains.", "The headwaters and upper course of the Pit River are on the Modoc Plateau; downstream, the Pit cuts a canyon through the southern reaches of the Cascades.", "In contrast, the Columbia cuts through the range nearly a thousand miles from its source in the Rocky Mountains.", "The gorge is known for its strong and steady winds, scenic beauty, and its role as an important transportation link.", "The river continues west, bending sharply to the north-northwest near Portland and Vancouver, Washington, at the Willamette River confluence.", "Here the river slows considerably, dropping sediment that might otherwise form a river delta.", "Near Longview, Washington and the Cowlitz River confluence, the river turns west again.", "The Columbia empties into the Pacific Ocean just west of Astoria, Oregon, over the Columbia Bar, a shifting sandbar that makes the river's mouth one of the most hazardous stretches of water to navigate in the world.", "Because of the danger and the many shipwrecks near the mouth, it acquired a reputation as the \"Graveyard of Ships\".The Columbia drains an area of about .", "Its drainage basin covers nearly all of Idaho, large portions of British Columbia, Oregon, and Washington, and ultimately all of Montana west of the Continental Divide, and small portions of Wyoming, Utah, and Nevada; the total area is similar to the size of France.", "Roughly of the river's length and 85 percent of its drainage basin are in the US.", "The Columbia is the twelfth-longest river and has the sixth-largest drainage basin in the United States.", "In Canada, where the Columbia flows for and drains , the river ranks 23rd in length, and the Canadian part of its basin ranks 13th in size among Canadian basins.", "The Columbia shares its name with nearby places, such as British Columbia, as well as with landforms and bodies of water.=== Discharge ===Bathymetric map of the mouth of the Columbia RiverWith an average flow at the mouth of about , the Columbia is the largest river by discharge flowing into the Pacific from the Americas and is the fourth-largest by volume in the U.S.", "The average flow where the river crosses the international border between Canada and the United States is from a drainage basin of .", "This amounts to about 15 percent of the entire Columbia watershed.", "The Columbia's highest recorded flow, measured at The Dalles, was in June 1894, before the river was dammed.", "The lowest flow recorded at The Dalles was on April 16, 1968, and was caused by the initial closure of the John Day Dam, upstream.", "The Dalles is about from the mouth; the river at this point drains about or about 91 percent of the total watershed.", "Flow rates on the Columbia are affected by many large upstream reservoirs, many diversions for irrigation, and, on the lower stretches, reverse flow from the tides of the Pacific Ocean.", "The National Ocean Service observes water levels at six tide gauges and issues tide forecasts for twenty-two additional locations along the river between the entrance at the North Jetty and the base of Bonneville Dam, its head of tide.The Columbia River multiannual average discharge: Water period (cfs) (m3/s) (km3)Columbia River at the mouth, Oregon, Washington1892 - 1999257,8007,3002301928 - 1965251,9007,1342251951 - 1980265,0007,5042371926 - 2022267,6007,579239Columbia River at Port Westward, Oregon, 86 km from the mouth1879 - 2004251,1007,1102241879 - 2022249,2007,0572231926 - 2022264,2007,4812361992 - 2022233,9006,625209Columbia River at The Dalles, Oregon, 304 km from the mouth1858 - 1899221,8006,2801981970 - 2004200,2005,6701791879 - 2018189,7005,371170" ], [ "Geology", "Drumheller Channels, part of the Channeled Scablands formed by the Missoula FloodsWhen the rifting of Pangaea, due to the process of plate tectonics, pushed North America away from Europe and Africa and into the Panthalassic Ocean (ancestor to the modern Pacific Ocean), the Pacific Northwest was not part of the continent.", "As the North American continent moved westward, the Farallon Plate subducted under its western margin.", "As the plate subducted, it carried along island arcs which were accreted to the North American continent, resulting in the creation of the Pacific Northwest between 150 and 90 million years ago.", "The general outline of the Columbia Basin was not complete until between 60 and 40 million years ago, but it lay under a large inland sea later subject to uplift.", "Between 50 and 20 million years ago, from the Eocene through the Miocene eras, tremendous volcanic eruptions frequently modified much of the landscape traversed by the Columbia.", "The lower reaches of the ancestral river passed through a valley near where Mount Hood later arose.", "Carrying sediments from erosion and erupting volcanoes, it built a thick delta that underlies the foothills on the east side of the Coast Range near Vernonia in northwestern Oregon.", "Between 17 million and 6 million years ago, huge outpourings of flood basalt lava covered the Columbia River Plateau and forced the lower Columbia into its present course.", "The modern Cascade Range began to uplift 5 to 4 million years ago.", "Cutting through the uplifting mountains, the Columbia River significantly deepened the Columbia River Gorge.The river and its drainage basin experienced some of the world's greatest known catastrophic floods toward the end of the last ice age.", "The periodic rupturing of ice dams at Glacial Lake Missoula resulted in the Missoula Floods, with discharges exceeding the combined flow of all the other rivers in the world, dozens of times over thousands of years.", "The exact number of floods is unknown, but geologists have documented at least 40; evidence suggests that they occurred between about 19,000 and 13,000 years ago.Panoramic view of Columbia River Gorge from Dog Mountain in WashingtonThe floodwaters rushed across eastern Washington, creating the channeled scablands, which are a complex network of dry canyon-like channels, or coulees that are often braided and sharply gouged into the basalt rock underlying the region's deep topsoil.", "Numerous flat-topped buttes with rich soil stand high above the chaotic scablands.", "Constrictions at several places caused the floodwaters to pool into large temporary lakes, such as Lake Lewis, in which sediments were deposited.", "Water depths have been estimated at at Wallula Gap and over modern Portland, Oregon.", "Sediments were also deposited when the floodwaters slowed in the broad flats of the Quincy, Othello, and Pasco Basins.", "The floods' periodic inundation of the lower Columbia River Plateau deposited rich sediments; 21st-century farmers in the Willamette Valley \"plow fields of fertile Montana soil and clays from Washington's Palouse\".Over the last several thousand years a series of large landslides have occurred on the north side of the Columbia River Gorge, sending massive amounts of debris south from Table Mountain and Greenleaf Peak into the gorge near the present site of Bonneville Dam.", "The most recent and significant is known as the Bonneville Slide, which formed a massive earthen dam, filling of the river's length.", "Various studies have placed the date of the Bonneville Slide anywhere between 1060 and 1760 AD; the idea that the landslide debris present today was formed by more than one slide is relatively recent and may explain the large range of estimates.", "It has been suggested that if the later dates are accurate there may be a link with the 1700 Cascadia earthquake.", "The pile of debris resulting from the Bonneville Slide blocked the river until rising water finally washed away the sediment.", "It is not known how long it took the river to break through the barrier; estimates range from several months to several years.", "Much of the landslide's debris remained, forcing the river about south of its previous channel and forming the Cascade Rapids.", "In 1938, the construction of Bonneville Dam inundated the rapids as well as the remaining trees that could be used to refine the estimated date of the landslide.In 1980, the eruption of Mount St. Helens deposited large amounts of sediment in the lower Columbia, temporarily reducing the depth of the shipping channel by ." ], [ "Indigenous peoples", "Chief Joseph of the Nez Perce peopleHumans have inhabited the Columbia's watershed for more than 15,000 years, with a transition to a sedentary lifestyle based mainly on salmon starting about 3,500 years ago.", "In 1962, archaeologists found evidence of human activity dating back 11,230 years at the Marmes Rockshelter, near the confluence of the Palouse and Snake rivers in eastern Washington.", "In 1996 the skeletal remains of a 9,000-year-old prehistoric man (dubbed Kennewick Man) were found near Kennewick, Washington.", "The discovery rekindled debate in the scientific community over the origins of human habitation in North America and sparked a protracted controversy over whether the scientific or Native American community was entitled to possess and/or study the remains.Many different Native Americans and First Nations peoples have a historical and continuing presence on the Columbia.", "South of the Canada–US border, the Colville, Spokane, Coeur d'Alene, Yakama, Nez Perce, Cayuse, Palus, Umatilla, Cowlitz, and the Confederated Tribes of Warm Springs live along the US stretch.", "Along the upper Snake River and Salmon River, the Shoshone Bannock tribes are present.", "The Sinixt or Lakes people lived on the lower stretch of the Canadian portion, while above that the Shuswap people (Secwepemc in their own language) reckon the whole of the upper Columbia east to the Rockies as part of their territory.", "The Canadian portion of the Columbia Basin outlines the traditional homelands of the Canadian Kootenay–Ktunaxa.The Chinook tribe, which is not federally recognized, who live near the lower Columbia River, call it '''' or '''' in the Upper Chinook (Kiksht) language, and it is ''Nch’i-Wàna'' or ''Nchi wana'' to the Sahaptin (Ichishkíin Sɨ́nwit)-speaking peoples of its middle course in present-day Washington.", "The river is known as '''' by the Sinixt people, who live in the area of the Arrow Lakes in the river's upper reaches in Canada.", "All three terms essentially mean \"the big river\".Oral histories describe the formation and destruction of the Bridge of the Gods, a land bridge that connected the Oregon and Washington sides of the river in the Columbia River Gorge.", "The bridge, which aligns with geological records of the Bonneville Slide, was described in some stories as the result of a battle between gods, represented by Mount Adams and Mount Hood, in their competition for the affection of a goddess, represented by Mount St. Helens.", "Native American stories about the bridge differ in their details but agree in general that the bridge permitted increased interaction between tribes on the north and south sides of the river.Horses, originally acquired from Spanish New Mexico, spread widely via native trade networks, reaching the Shoshone of the Snake River Plain by 1700.The Nez Perce, Cayuse, and Flathead people acquired their first horses around 1730.Along with horses came aspects of the emerging plains culture, such as equestrian and horse training skills, greatly increased mobility, hunting efficiency, trade over long distances, intensified warfare, the linking of wealth and prestige to horses and war, and the rise of large and powerful tribal confederacies.", "The Nez Perce and Cayuse kept large herds and made annual long-distance trips to the Great Plains for bison hunting, adopted the plains culture to a significant degree, and became the main conduit through which horses and the plains culture diffused into the Columbia River region.", "Other peoples acquired horses and aspects of the plains culture unevenly.", "The Yakama, Umatilla, Palus, Spokane, and Coeur d'Alene maintained sizable herds of horses and adopted some of the plains cultural characteristics, but fishing and fish-related economies remained important.", "Less affected groups included the Molala, Klickitat, Wenatchi, Okanagan, and Sinkiuse-Columbia peoples, who owned small numbers of horses and adopted few plains culture features.", "Some groups remained essentially unaffected, such as the Sanpoil and Nespelem people, whose culture remained centered on fishing.Natives of the region encountered foreigners at several times and places during the 18th and 19th centuries.", "European and American vessels explored the coastal area around the mouth of the river in the late 18th century, trading with local natives.", "The contact would prove devastating to the Indian tribes; a large portion of their population was wiped out by a smallpox epidemic.", "Canadian explorer Alexander Mackenzie crossed what is now interior British Columbia in 1793.From 1805 to 1806, the Lewis and Clark Expedition entered the Oregon Country along the Clearwater and Snake rivers, and encountered numerous small settlements of natives.", "Their records recount tales of hospitable traders who were not above stealing small items from the visitors.", "They also noted brass teakettles, a British musket, and other artifacts that had been obtained in trade with coastal tribes.", "From the earliest contact with westerners, the natives of the mid- and lower Columbia were not tribal, but instead congregated in social units no larger than a village, and more often at a family level; these units would shift with the season as people moved about, following the salmon catch up and down the river's tributaries.Sparked by the 1847 Whitman Massacre, a number of violent battles were fought between American settlers and the region's natives.", "The subsequent Indian Wars, especially the Yakima War, decimated the native population and removed much land from native control.", "As years progressed, the right of natives to fish along the Columbia became the central issue of contention with the states, commercial fishers, and private property owners.", "The US Supreme Court upheld fishing rights in landmark cases in 1905 and 1918, as well as the 1974 case ''United States v. Washington'', commonly called the Boldt Decision.Dipnet fishing at Celilo Falls, 1941Fish were central to the culture of the region's natives, both as sustenance and as part of their religious beliefs.", "Natives drew fish from the Columbia at several major sites, which also served as trading posts.", "Celilo Falls, located east of the modern city of The Dalles, was a vital hub for trade and the interaction of different cultural groups, being used for fishing and trading for 11,000 years.", "Prior to contact with westerners, villages along this stretch may have at times had a population as great as 10,000.The site drew traders from as far away as the Great Plains.The Cascades Rapids of the Columbia River Gorge, and Kettle Falls and Priest Rapids in eastern Washington, were also major fishing and trading sites.In prehistoric times the Columbia's salmon and steelhead runs numbered an estimated annual average of 10 to 16 million fish.", "In comparison, the largest run since 1938 was in 1986, with 3.2 million fish entering the Columbia.", "The annual catch by natives has been estimated at .", "The most important and productive native fishing site was located at Celilo Falls, which was perhaps the most productive inland fishing site in North America.", "The falls were located at the border between Chinookan- and Sahaptian-speaking peoples and served as the center of an extensive trading network across the Pacific Plateau.", "Celilo was the oldest continuously inhabited community on the North American continent.Salmon canneries established by white settlers beginning in 1866 had a strong negative impact on the salmon population, and in 1908 US President Theodore Roosevelt observed that the salmon runs were but a fraction of what they had been 25 years prior.As river development continued in the 20th century, each of these major fishing sites was flooded by a dam, beginning with Cascades Rapids in 1938.The development was accompanied by extensive negotiations between natives and US government agencies.", "The Confederated Tribes of Warm Springs, a coalition of various tribes, adopted a constitution and incorporated after the 1938 completion of the Bonneville Dam flooded Cascades Rapids; Still, in the 1930s, there were natives who lived along the river and fished year round, moving along with the fish's migration patterns throughout the seasons.", "The Yakama were slower to do so, organizing a formal government in 1944.In the 21st century, the Yakama, Nez Perce, Umatilla, and Warm Springs tribes all have treaty fishing rights along the Columbia and its tributaries.In 1957 Celilo Falls was submerged by the construction of The Dalles Dam, and the native fishing community was displaced.", "The affected tribes received a $26.8 million settlement for the loss of Celilo and other fishing sites submerged by The Dalles Dam.", "The Confederated Tribes of Warm Springs used part of its $4 million settlement to establish the Kah-Nee-Ta resort south of Mount Hood." ], [ "New waves of explorers", "Multnomah Falls, painted by James W. Alden, 1857Some historians believe that Japanese or Chinese vessels blown off course reached the Northwest Coast long before Europeans—possibly as early as 219 BCE.", "Historian Derek Hayes claims that \"It is a near certainty that Japanese or Chinese people arrived on the northwest coast long before any European.\"", "It is unknown whether they landed near the Columbia.", "Evidence exists that Spanish castaways reached the shore in 1679 and traded with the Clatsop; if these were the first Europeans to see the Columbia, they failed to send word home to Spain.In the 18th century, there was strong interest in discovering a Northwest Passage that would permit navigation between the Atlantic (or inland North America) and the Pacific Ocean.", "Many ships in the area, especially those under Spanish and British command, searched the northwest coast for a large river that might connect to Hudson Bay or the Missouri River.", "The first documented European discovery of the Columbia River was that of Bruno de Heceta, who in 1775 sighted the river's mouth.", "On the advice of his officers, he did not explore it, as he was short-staffed and the current was strong.", "He considered it a bay, and called it ''Ensenada de Asunción'' (''Assumption Cove'').", "Later Spanish maps, based on his sighting, showed a river, labeled ''Río de San Roque'' (''The Saint Roch River''), or an entrance, called ''Entrada de Hezeta'', named for Bruno de Hezeta, who sailed the region.", "Following Hezeta's reports, British maritime fur trader Captain John Meares searched for the river in 1788 but concluded that it did not exist.", "He named Cape Disappointment for the non-existent river, not realizing the cape marks the northern edge of the river's mouth.What happened next would form the basis for decades of both cooperation and dispute between British and American exploration of, and ownership claim to, the region.", "Royal Navy commander George Vancouver sailed past the mouth in April 1792 and observed a change in the water's color, but he accepted Meares' report and continued on his journey northward.", "Later that month, Vancouver encountered the American captain Robert Gray at the Strait of Juan de Fuca.", "Gray reported that he had seen the entrance to the Columbia and had spent nine days trying but failing to enter.Carver's map from 1778, showing the River of the West, New Albion, Lake Winnipeg, and the Mountains of Bright StoneOn May 12, 1792, Gray returned south and crossed the Columbia Bar, becoming the first known explorer of European descent to enter the river.", "Gray's fur trading mission had been financed by Boston merchants, who outfitted him with a private vessel named ''Columbia Rediviva''; he named the river after the ship on May 18.Gray spent nine days trading near the mouth of the Columbia, then left without having gone beyond upstream.", "The farthest point reached was Grays Bay at the mouth of Grays River.", "Gray's discovery of the Columbia River was later used by the United States to support its claim to the Oregon Country, which was also claimed by Russia, Great Britain, Spain and other nations.In October 1792, Vancouver sent Lieutenant William Robert Broughton, his second-in-command, up the river.", "Broughton got as far as the Sandy River at the western end of the Columbia River Gorge, about upstream, sighting and naming Mount Hood.", "Broughton formally claimed the river, its drainage basin, and the nearby coast for Britain.", "In contrast, Gray had not made any formal claims on behalf of the United States.", "''Columbia River, Cascade Mountains, Oregon'', (1876) by Vincent Colyer (oil on canvas).", "Beacon Rock is visible on the left.Detail from the Lewis and Clark Expedition map.", "The Willamette River is shown as the \"Multnomah\", while the Snake River is \"Lewis's River\".", "(See complete map.", ")Because the Columbia was at the same latitude as the headwaters of the Missouri River, there was some speculation that Gray and Vancouver had discovered the long-sought Northwest Passage.", "A 1798 British map showed a dotted line connecting the Columbia with the Missouri.", "When the American explorers Meriwether Lewis and William Clark charted the vast, unmapped lands of the American West in their overland expedition (1803–1805), they found no passage between the rivers.", "After crossing the Rocky Mountains, Lewis and Clark built dugout canoes and paddled down the Snake River, reaching the Columbia near the present-day Tri-Cities, Washington.", "They explored a few miles upriver, as far as Bateman Island, before heading down the Columbia, concluding their journey at the river's mouth and establishing Fort Clatsop, a short-lived establishment that was occupied for less than three months.Canadian explorer David Thompson, of the North West Company, spent the winter of 180708 at Kootanae House near the source of the Columbia at present-day Invermere, BC.", "Over the next few years he explored much of the river and its northern tributaries.", "In 1811 he traveled down the Columbia to the Pacific Ocean, arriving at the mouth just after John Jacob Astor's Pacific Fur Company had founded Astoria.", "On his return to the north, Thompson explored the one remaining part of the river he had not yet seen, becoming the first Euro-descended person to travel the entire length of the river.In 1825, the Hudson's Bay Company (HBC) established Fort Vancouver on the bank of the Columbia, in what is now Vancouver, Washington, as the headquarters of the company's Columbia District, which encompassed everything west of the Rocky Mountains, north of California, and south of Russian-claimed Alaska.", "Chief Factor John McLoughlin, a physician who had been in the fur trade since 1804, was appointed superintendent of the Columbia District.", "The HBC reoriented its Columbia District operations toward the Pacific Ocean via the Columbia, which became the region's main trunk route.", "In the early 1840s Americans began to colonize the Oregon country in large numbers via the Oregon Trail, despite the HBC's efforts to discourage American settlement in the region.", "For many the final leg of the journey involved travel down the lower Columbia River to Fort Vancouver.", "This part of the Oregon Trail, the treacherous stretch from The Dalles to below the Cascades, could not be traversed by horses or wagons (only watercraft, at great risk).", "This prompted the 1846 construction of the Barlow Road.In the Treaty of 1818 the United States and Britain agreed that both nations were to enjoy equal rights in Oregon Country for 10 years.", "By 1828, when the so-called \"joint occupation\" was renewed indefinitely, it seemed probable that the lower Columbia River would in time become the border between the two nations.", "For years the Hudson's Bay Company successfully maintained control of the Columbia River and American attempts to gain a foothold were fended off.", "In the 1830s, American religious missions were established at several locations in the lower Columbia River region.", "In the 1840s a mass migration of American settlers undermined British control.", "The Hudson's Bay Company tried to maintain dominance by shifting from the fur trade, which was in decline, to exporting other goods such as salmon and lumber.", "Colonization schemes were attempted, but failed to match the scale of American settlement.", "Americans generally settled south of the Columbia, mainly in the Willamette Valley.", "The Hudson's Bay Company tried to establish settlements north of the river, but nearly all the British colonists moved south to the Willamette Valley.", "The hope that the British colonists might dilute the American presence in the valley failed in the face of the overwhelming number of American settlers.", "These developments rekindled the issue of \"joint occupation\" and the boundary dispute.", "While some British interests, especially the Hudson's Bay Company, fought for a boundary along the Columbia River, the Oregon Treaty of 1846 set the boundary at the 49th parallel.", "As part of the treaty, the British retained all areas north of the line while the United States acquired the south.", "The Columbia River became much of the border between the U.S. territories of Oregon and Washington.", "Oregon became a U.S. state in 1859, while Washington later entered into the Union in 1889.By the turn of the 20th century, the difficulty of navigating the Columbia was seen as an impediment to the economic development of the Inland Empire region east of the Cascades.", "The dredging and dam building that followed would permanently alter the river, disrupting its natural flow but also providing electricity, irrigation, navigability and other benefits to the region." ], [ "Navigation", "The mouth of the Columbia is just past Astoria, Oregon; ships must navigate the treacherous Columbia Bar (near horizon, not visible in this picture) to enter or exit the river.Hassalo'' runs the Cascades Rapids, May 26, 1888.The rapids are now submerged under the pool of the Bonneville Dam.Benson log raft, containing an entire year's worth of logs from one timber camp, heads downriver in 1906American captain Robert Gray and British captain George Vancouver, who explored the river in 1792, proved that it was possible to cross the Columbia Bar.", "Many of the challenges associated with that feat remain today; even with modern engineering alterations to the mouth of the river, the strong currents and shifting sandbar make it dangerous to pass between the river and the Pacific Ocean.The use of steamboats along the river, beginning with the British ''Beaver'' in 1836 and followed by American vessels in 1850, contributed to the rapid settlement and economic development of the region.", "Steamboats operated in several distinct stretches of the river: on its lower reaches, from the Pacific Ocean to Cascades Rapids; from the Cascades to the Dalles-Celilo Falls; from Celilo to Priests Rapids; on the Wenatchee Reach of eastern Washington; on British Columbia's Arrow Lakes; and on tributaries like the Willamette, the Snake and Kootenay Lake.", "The boats, initially powered by burning wood, carried passengers and freight throughout the region for many years.", "Early railroads served to connect steamboat lines interrupted by waterfalls on the river's lower reaches.", "In the 1880s, railroads maintained by companies such as the Oregon Railroad and Navigation Company began to supplement steamboat operations as the major transportation links along the river.=== Opening the passage to Lewiston ===As early as 1881, industrialists proposed altering the natural channel of the Columbia to improve navigation.", "Changes to the river over the years have included the construction of jetties at the river's mouth, dredging, and the construction of canals and navigation locks.", "Today, ocean freighters can travel upriver as far as Portland and Vancouver, and barges can reach as far inland as Lewiston, Idaho.The shifting Columbia Bar makes passage between the river and the Pacific Ocean difficult and dangerous, and numerous rapids along the river hinder navigation.", "''Pacific Graveyard,'' a 1964 book by James A. Gibbs, describes the many shipwrecks near the mouth of the Columbia.", "Jetties, first constructed in 1886, extend the river's channel into the ocean.", "Strong currents and the shifting sandbar remain a threat to ships entering the river and necessitate continuous maintenance of the jetties.In 1891, the Columbia was dredged to enhance shipping.", "The channel between the ocean and Portland and Vancouver was deepened from to .", "''The Columbian'' called for the channel to be deepened to as early as 1905, but that depth was not attained until 1976.Cascade Locks and Canal were first constructed in 1896 around the Cascades Rapids, enabling boats to travel safely through the Columbia River Gorge.", "The Celilo Canal, bypassing Celilo Falls, opened to river traffic in 1915.In the mid-20th century, the construction of dams along the length of the river submerged the rapids beneath a series of reservoirs.", "An extensive system of locks allowed ships and barges to pass easily between reservoirs.", "A navigation channel reaching Lewiston, Idaho, along the Columbia and Snake rivers, was completed in 1975.Among the main commodities are wheat and other grains, mainly for export.", "As of 2016, the Columbia ranked third, behind the Mississippi and Paraná rivers, among the world's largest export corridors for grain.The 1980 eruption of Mount St. Helens caused mudslides in the area, which reduced the Columbia's depth by for a stretch, disrupting Portland's economy.=== Deeper shipping channel ===The ''Essayons'', one of three Army Corps of Engineers dredgers tasked with ongoing maintenance of the Columbia's shipping channel, began service in 1983.Efforts to maintain and improve the navigation channel have continued to the present day.", "In 1990 a new round of studies examined the possibility of further dredging on the lower Columbia.", "The plans were controversial from the start because of economic and environmental concerns.In 1999, Congress authorized deepening the channel between Portland and Astoria from , which will make it possible for large container and grain ships to reach Portland and Vancouver.", "The project has met opposition because of concerns about stirring up toxic sediment on the riverbed.", "Portland-based Northwest Environmental Advocates brought a lawsuit against the Army Corps of Engineers, but it was rejected by the Ninth U.S.", "Circuit Court of Appeals in August 2006.The project includes measures to mitigate environmental damage; for instance, the US Army Corps of Engineers must restore 12 times the area of wetland damaged by the project.", "In early 2006, the Corps spilled of hydraulic oil into the Columbia, drawing further criticism from environmental organizations.Work on the project began in 2005 and concluded in 2010.The project's cost is estimated at $150 million.", "The federal government is paying 65 percent, Oregon and Washington are paying $27 million each, and six local ports are also contributing to the cost." ], [ "Dams", "Fish ladder at John Day Dam.", "This dam is frequently referred to as the \"fish killer\", and its reservoir forms the deadliest stretch of the river for young salmon.Bonneville and The Dalles, as seen from Rowena CrestKinbasket Lake, a reservoir on the Columbia RiverIn 1902, the United States Bureau of Reclamation was established to aid in the economic development of arid western states.", "One of its major undertakings was building Grand Coulee Dam to provide irrigation for the of the Columbia Basin Project in central Washington.", "With the onset of World War II, the focus of dam construction shifted to production of hydroelectricity.", "Irrigation efforts resumed after the war.River development occurred within the structure of the 1909 International Boundary Waters Treaty between the United States and Canada.", "The United States Congress passed the Rivers and Harbors Act of 1925, which directed the U.S. Army Corps of Engineers and the Federal Power Commission to explore the development of the nation's rivers.", "This prompted agencies to conduct the first formal financial analysis of hydroelectric development; the reports produced by various agencies were presented in House Document 308.Those reports, and subsequent related reports, are referred to as 308 Reports.In the late 1920s, political forces in the Northwestern United States generally favored the private development of hydroelectric dams along the Columbia.", "But the overwhelming victories of gubernatorial candidate George W. Joseph in the 1930 Republican primary, and later his law partner Julius Meier, were understood to demonstrate strong public support for public ownership of dams.", "In 1933, President Franklin D. Roosevelt signed a bill that enabled the construction of the Bonneville and Grand Coulee dams as public works projects.", "The legislation was attributed to the efforts of Oregon Senator Charles McNary, Washington Senator Clarence Dill, and Oregon Congressman Charles Martin, among others.In 1948, floods swept through the Columbia watershed, destroying Vanport, then the second largest city in Oregon, and impacting cities as far north as Trail, BC.", "The flooding prompted the U.S. Congress to pass the Flood Control Act of 1950, authorizing the federal development of additional dams and other flood control mechanisms.", "By that time local communities had become wary of federal hydroelectric projects, and sought local control of new developments; a public utility district in Grant County, Washington, ultimately began construction of the dam at Priest Rapids.In the 1960s, the United States and Canada signed the Columbia River Treaty, which focused on flood control and the maximization of downstream power generation.", "Canada agreed to build dams and provide reservoir storage, and the United States agreed to deliver to Canada one-half of the increase in United States downstream power benefits as estimated five years in advance.", "Canada's obligation was met by building three dams (two on the Columbia, and one on the Duncan River), the last of which was completed in 1973.Today the main stem of the Columbia River has fourteen dams, of which three are in Canada and eleven in the United States.", "Four mainstem dams and four lower Snake River dams contain navigation locks to allow ship and barge passage from the ocean as far as Lewiston, Idaho.", "The river system as a whole has more than 400 dams for hydroelectricity and irrigation.", "The dams address a variety of demands, including flood control, navigation, stream flow regulation, storage, and delivery of stored waters, reclamation of public lands and Indian reservations, and the generation of hydroelectric power.The larger U.S. dams are owned and operated by the federal government (some by the Army Corps of Engineers and some by the Bureau of Reclamation), while the smaller dams are operated by public utility districts and private power companies.", "The federally operated system is known as the Federal Columbia River Power System, which includes 31 dams on the Columbia and its tributaries.", "The system has altered the seasonal flow of the river to meet higher electricity demands during the winter.", "At the beginning of the 20th century, roughly 75 percent of the Columbia's flow occurred in the summer, between April and September.", "By 1980, the summer proportion had been lowered to about 50 percent, essentially eliminating the seasonal pattern.The installation of dams dramatically altered the landscape and ecosystem of the river.", "At one time, the Columbia was one of the top salmon-producing river systems in the world.", "Previously active fishing sites, such as Celilo Falls in the eastern Columbia River Gorge, have exhibited a sharp decline in fishing along the Columbia in the last century, and salmon populations have been dramatically reduced.", "Fish ladders have been installed at some dam sites to help the fish journey to spawning waters.", "Chief Joseph Dam has no fish ladders and completely blocks fish migration to the upper half of the Columbia River system.=== Irrigation ===Prominent dams of the Columbia River Basin.", "Color indicates dam ownership: The Bureau of Reclamation's Columbia Basin Project focused on the generally dry region of central Washington known as the Columbia Basin, which features rich loess soil.", "Several groups developed competing proposals, and in 1933, President Franklin D. Roosevelt authorized the Columbia Basin Project.", "The Grand Coulee Dam was the project's central component; upon completion, it pumped water up from the Columbia to fill the formerly dry Grand Coulee, forming Banks Lake.", "By 1935, the intended height of the dam was increased from a range between to , a height that would extend the lake impounded by the dam to the Canada–United States border; the project had grown from a local New Deal relief measure to a major national project.The project's initial purpose was irrigation, but the onset of World War II created a high electricity demand, mainly for aluminum production and for the development of nuclear weapons at the Hanford Site.", "Irrigation began in 1951.The project provides water to more than of fertile but arid land in central Washington, transforming the region into a major agricultural center.", "Important crops include orchard fruit, potatoes, alfalfa, mint, beans, beets, and wine grapes.Since 1750, the Columbia has experienced six multi-year droughts.", "The longest, lasting 12 years in the mid‑19th century, reduced the river's flow to 20 percent below average.", "Scientists have expressed concern that a similar drought would have grave consequences in a region so dependent on the Columbia.", "In 1992–1993, a lesser drought affected farmers, hydroelectric power producers, shippers, and wildlife managers.Many farmers in central Washington build dams on their property for irrigation and to control frost on their crops.", "The Washington Department of Ecology, using new techniques involving aerial photographs, estimated there may be as many as a hundred such dams in the area, most of which are illegal.", "Six such dams have failed in recent years, causing hundreds of thousands of dollars of damage to crops and public roads.", "Fourteen farms in the area have gone through the permitting process to build such dams legally.=== Hydroelectricity ===The Columbia's heavy flow and large elevation drop over a short distance, , give it tremendous capacity for hydroelectricity generation.", "In comparison, the Mississippi drops less than .", "The Columbia alone possesses one-third of the United States's hydroelectric potential.", "In 2012, the river and its tributaries accounted for 29 GW of hydroelectric generating capacity, contributing 44 percent of the total hydroelectric generation in the nation.", "''Roll on, Columbia, roll on, roll on, Columbia, roll on / Your power is turning our darkness to dawn / Roll on, Columbia, roll on.", "''Lyrics from Woody Guthrie's 1941 song Roll on Columbia, written for the Bonneville Power Administration.The largest of the 150 hydroelectric projects, the Grand Coulee Dam and Chief Joseph Dam are also the largest in the United States.", "As of 2017, Grand Coulee is the fifth largest hydroelectric plant in the world.Inexpensive hydropower supported the location of a large aluminum industry in the region because its reduction from bauxite requires large amounts of electricity.", "Until 2000, the Northwestern United States produced up to 17 percent of the world's aluminum and 40 percent of the aluminum produced in the United States.", "The commoditization of power in the early 21st century, coupled with a drought that reduced the generation capacity of the river, damaged the industry and by 2001, Columbia River aluminum producers had idled 80 percent of its production capacity.", "By 2003, the entire United States produced only 15 percent of the world's aluminum and many smelters along the Columbia had gone dormant or out of business.Power remains relatively inexpensive along the Columbia, and since the mid-2000 several global enterprises have moved server farm operations into the area to avail themselves of cheap power.", "Downriver of Grand Coulee, each dam's reservoir is closely regulated by the Bonneville Power Administration (BPA), the U.S. Army Corps of Engineers, and various Washington public utility districts to ensure flow, flood control, and power generation objectives are met.", "Increasingly, hydro-power operations are required to meet standards under the U.S.", "Endangered Species Act and other agreements to manage operations to minimize impacts on salmon and other fish, and some conservation and fishing groups support removing four dams on the lower Snake River, the largest tributary of the Columbia.In 1941, the BPA hired Oklahoma folksinger Woody Guthrie to write songs for a documentary film promoting the benefits of hydropower.", "In the month he spent traveling the region Guthrie wrote 26 songs, which have become an important part of the cultural history of the region." ], [ "Ecology and environment", "=== Fish migration ===Seining salmon on the Columbia River, 1914Eagle Creek in Oregon, November 2007.The Columbia supports several species of anadromous fish that migrate between the Pacific Ocean and freshwater tributaries of the river.", "Sockeye salmon, Coho and Chinook (\"king\") salmon, and steelhead, all of the genus ''Oncorhynchus'', are ocean fish that migrate up the rivers at the end of their life cycles to spawn.", "White sturgeon, which take 15 to 25 years to mature, typically migrate between the ocean and the upstream habitat several times during their lives.Salmon populations declined dramatically after the establishment of canneries in 1867.In 1879 it was reported that 545,450 salmon, with an average weight of were caught (in a recent season) and mainly canned for export to England.", "A can weighing could be sold for 8d or 9d.", "By 1908, there was widespread concern about the decline of salmon and sturgeon.", "In that year, the people of Oregon passed two laws under their newly instituted program of citizens' initiatives limiting fishing on the Columbia and other rivers.", "Then in 1948, another initiative banned the use of seine nets (devices already used by Native Americans, and refined by later settlers) altogether.Dams interrupt the migration of anadromous fish.", "Salmon and steelhead return to the streams in which they were born to spawn; where dams prevent their return, entire populations of salmon die.", "Some of the Columbia and Snake River dams employ fish ladders, which are effective to varying degrees at allowing these fish to travel upstream.", "Another problem exists for the juvenile salmon headed downstream to the ocean.", "Previously, this journey would have taken two to three weeks.", "With river currents slowed by the dams, and the Columbia converted from a wild river to a series of slackwater pools, the journey can take several months, which increases the mortality rate.", "In some cases, the Army Corps of Engineers transports juvenile fish downstream by truck or river barge.", "The Chief Joseph Dam and several dams on the Columbia's tributaries entirely block migration, and there are no migrating fish on the river above these dams.", "Sturgeons have different migration habits and can survive without ever visiting the ocean.", "In many upstream areas cut off from the ocean by dams, sturgeon simply live upstream of the dam.Not all fish have suffered from the modifications to the river; the northern pikeminnow (formerly known as the ''squawfish'') thrives in the warmer, slower water created by the dams.", "Research in the mid-1980s found that juvenile salmon were suffering substantially from the predatory pikeminnow, and in 1990, in the interest of protecting salmon, a \"bounty\" program was established to reward anglers for catching pikeminnow.In 1994, the salmon catch was smaller than usual in the rivers of Oregon, Washington, and British Columbia, causing concern among commercial fishermen, government agencies, and tribal leaders.", "US government intervention, to which the states of Alaska, Idaho, and Oregon objected, included an 11-day closure of an Alaska fishery.", "In April 1994 the Pacific Fisheries Management Council unanimously approved the strictest regulations in 18 years, banning all commercial salmon fishing for that year from Cape Falcon north to the Canada–US border.", "In the winter of 1994, the return of coho salmon far exceeded expectations, which was attributed in part to the fishing ban.Also in 1994, United States Secretary of the Interior Bruce Babbitt proposed the removal of several Pacific Northwest dams because of their impact on salmon spawning.", "The Northwest Power Planning Council approved a plan that provided more water for fish and less for electricity, irrigation, and transportation.", "Environmental advocates have called for the removal of certain dams in the Columbia system in the years since.", "Of the 227 major dams in the Columbia River drainage basin, the four Washington dams on the lower Snake River are often identified for removal, for example in an ongoing lawsuit concerning a Bush administration plan for salmon recovery.", "These dams and reservoirs limit the recovery of upriver salmon runs to Idaho's Salmon and Clearwater rivers.", "Historically, the Snake produced over 1.5 million spring and summer Chinook salmon, a number that has dwindled to several thousand in recent years.", "Idaho Power Company's Hells Canyon dams have no fish ladders (and do not pass juvenile salmon downstream), and thus allow no steelhead or salmon to migrate above Hells Canyon.", "In 2007, the destruction of the Marmot Dam on the Sandy River was the first dam removal in the system.", "Other Columbia Basin dams that have been removed include Condit Dam on Washington's White Salmon River, and the Milltown Dam on the Clark Fork in Montana.=== Pollution ===In southeastern Washington, a stretch of the river passes through the Hanford Site, established in 1943 as part of the Manhattan Project.", "The site served as a plutonium production complex, with nine nuclear reactors and related facilities along the banks of the river.", "From 1944 to 1971, pump systems drew cooling water from the river and, after treating this water for use by the reactors, returned it to the river.", "Before being released back into the river, the used water was held in large tanks known as retention basins for up to six hours.", "Longer-lived isotopes were not affected by this retention, and several terabecquerels entered the river every day.", "By 1957, the eight plutonium production reactors at Hanford dumped a daily average of 50,000 curies of radioactive material into the Columbia.", "These releases were kept secret by the federal government until the release of declassified documents in the late 1980s.", "Radiation was measured downstream as far west as the Washington and Oregon coasts.Nuclear reactors at the Hanford Site along the riverThe nuclear reactors were decommissioned at the end of the Cold War, and the Hanford site is the focus of one of the world's largest environmental cleanup, managed by the Department of Energy under the oversight of the Washington Department of Ecology and the Environmental Protection Agency.", "Nearby aquifers contain an estimated 270 billion US gallons (1 billion m3) of groundwater contaminated by high-level nuclear waste that has leaked out of Hanford's underground storage tanks.", ", 1 million US gallons (3,785 m3) of highly radioactive waste is traveling through groundwater toward the Columbia River.", "This waste is expected to reach the river in 12 to 50 years if cleanup does not proceed on schedule.In addition to concerns about nuclear waste, numerous other pollutants are found in the river.", "These include chemical pesticides, bacteria, arsenic, dioxins, and polychlorinated biphenyls (PCB).Studies have also found significant levels of toxins in fish and the waters they inhabit within the basin.", "Accumulation of toxins in fish threatens the survival of fish species, and human consumption of these fish can lead to health problems.", "Water quality is also an important factor in the survival of other wildlife and plants that grow in the Columbia River drainage basin.", "The states, Indian tribes, and federal government are all engaged in efforts to restore and improve the water, land, and air quality of the Columbia River drainage basin and have committed to work together to accomplish critical ecosystem restoration efforts.", "Several cleanup efforts are underway, including Superfund projects at Portland Harbor, Hanford, and Lake Roosevelt.Timber industry activity further contaminates river water, for example in the increased sediment runoff that results from clearcuts.", "The Northwest Forest Plan, a piece of federal legislation from 1994, mandated that timber companies consider the environmental impacts of their practices on rivers like the Columbia.On July 1, 2003, Christopher Swain became the first person to swim the Columbia River's entire length, to raise public awareness about the river's environmental health.=== Nutrient cycle ===Both natural and anthropogenic processes are involved in the cycling of nutrients in the Columbia River basin.", "Natural processes in the system include estuarine mixing of fresh and ocean waters, and climate variability patterns such as the Pacific Decadal Oscillation and the El Nino Southern Oscillation (both climatic cycles that affect the amount of regional snowpack and river discharge).", "Natural sources of nutrients in the Columbia River include weathering, leaf litter, salmon carcasses, runoff from its tributaries, and ocean estuary exchange.", "Major anthropogenic impacts on nutrients in the basin are due to fertilizers from agriculture, sewage systems, logging, and the construction of dams.Nutrient dynamics vary in the river basin from the headwaters to the main river and dams, to finally reaching the Columbia River estuary and ocean.", "Upstream in the headwaters, salmon runs are the main source of nutrients.", "Dams along the river impact nutrient cycling by increasing residence time of nutrients, and reducing the transport of silicate to the estuary, which directly impacts diatoms, a type of phytoplankton.", "The dams are also a barrier to salmon migration and can increase the amount of methane locally produced.", "The Columbia River estuary exports high rates of nutrients into the Pacific, except for nitrogen, which is delivered into the estuary by ocean upwelling sources." ], [ "Watershed", "Near The Gorge Amphitheatre in George, WashingtonMost of the Columbia's drainage basin (which, at , is about the size of France) lies roughly between the Rocky Mountains on the east and the Cascade Mountains on the west.", "In the United States and Canada the term watershed is often used to mean drainage basin.", "The term ''Columbia Basin'' is used to refer not only to the entire drainage basin but also to subsets of the river's watershed, such as the relatively flat and unforested area in eastern Washington bounded by the Cascades, the Rocky Mountains, and the Blue Mountains.", "Within the watershed are diverse landforms including mountains, arid plateaus, river valleys, rolling uplands, and deep gorges.", "Grand Teton National Park lies in the watershed, as well as parts of Yellowstone National Park, Glacier National Park, Mount Rainier National Park, and North Cascades National Park.", "Canadian National Parks in the watershed include Kootenay National Park, Yoho National Park, Glacier National Park, and Mount Revelstoke National Park.", "Hells Canyon, the deepest gorge in North America, and the Columbia Gorge are in the watershed.", "Vegetation varies widely, ranging from western hemlock and western redcedar in the moist regions to sagebrush in the arid regions.", "The watershed provides habitat for 609 known fish and wildlife species, including the bull trout, bald eagle, gray wolf, grizzly bear, and Canada lynx.The World Wide Fund for Nature (WWF) divides the waters of the Columbia and its tributaries into three freshwater ecoregions: Columbia Glaciated, Columbia Unglaciated, and Upper Snake.", "The Columbia Glaciated ecoregion, about a third of the total watershed, lies in the north and was covered with ice sheets during the Pleistocene.", "The ecoregion includes the mainstem Columbia north of the Snake River and tributaries such as the Yakima, Okanagan, Pend Oreille, Clark Fork, and Kootenay rivers.", "The effects of glaciation include a number of large lakes and a relatively low diversity of freshwater fish.", "The Upper Snake ecoregion is defined as the Snake River watershed above Shoshone Falls, which totally blocks fish migration.", "This region has 14 species of fish, many of which are endemic.", "The Columbia Unglaciated ecoregion makes up the rest of the watershed.", "It includes the mainstem Columbia below the Snake River and tributaries such as the Salmon, John Day, Deschutes, and lower Snake Rivers.", "Of the three ecoregions it is the richest in terms of freshwater species diversity.", "There are 35 species of fish, of which four are endemic.", "There are also high levels of mollusk endemism.In 2016, over eight million people lived within the Columbia's drainage basin.", "Of this total about 3.5 million people lived in Oregon, 2.1 million in Washington, 1.7 million in Idaho, half a million in British Columbia, and 0.4 million in Montana.", "Population in the watershed has been rising for many decades and is projected to rise to about 10 million by 2030.The highest population densities are found west of the Cascade Mountains along the I-5 corridor, especially in the Portland-Vancouver urban area.", "High densities are also found around Spokane, Washington, and Boise, Idaho.", "Although much of the watershed is rural and sparsely populated, areas with recreational and scenic values are growing rapidly.", "The central Oregon county of Deschutes is the fastest-growing in the state.", "Populations have also been growing just east of the Cascades in central Washington around the city of Yakima and the Tri-Cities area.", "Projections for the coming decades assume growth throughout the watershed.", "The Canadian part of the Okanagan subbasin is also growing rapidly.Climate varies greatly within the watershed.", "Elevation ranges from sea level at the river mouth to more than in the mountains, and temperatures vary with elevation.", "The highest peak is Mount Rainier, at .", "High elevations have cold winters and short cool summers; interior regions are subject to great temperature variability and severe droughts.", "Over some of the watershed, especially west of the Cascade Mountains, precipitation maximums occur in winter, when Pacific storms come ashore.", "Atmospheric conditions block the flow of moisture in summer, which is generally dry except for occasional thunderstorms in the interior.", "In some of the eastern parts of the watershed, especially shrub-steppe regions with Continental climate patterns, precipitation maximums occur in early summer.", "Annual precipitation varies from more than a year in the Cascades to less than in the interior.", "Much of the watershed gets less than a year.Several major North American drainage basins and many minor ones border the Columbia River's drainage basin.", "To the east, in northern Wyoming and Montana, the Continental Divide separates the Columbia watershed from the Mississippi-Missouri watershed, which empties into the Gulf of Mexico.", "To the northeast, mostly along the southern border between British Columbia and Alberta, the Continental Divide separates the Columbia watershed from the Nelson-Lake Winnipeg-Saskatchewan watershed, which empties into Hudson Bay.", "The Mississippi and Nelson watersheds are separated by the Laurentian Divide, which meets the Continental Divide at Triple Divide Peak near the headwaters of the Columbia's Flathead River tributary.", "This point marks the meeting of three of North America's main drainage patterns, to the Pacific Ocean, to Hudson Bay, and to the Atlantic Ocean via the Gulf of Mexico.Further north along the Continental Divide, a short portion of the combined Continental and Laurentian divides separate the Columbia watershed from the MacKenzie-Slave-Athabasca watershed, which empties into the Arctic Ocean.", "The Nelson and Mackenzie watersheds are separated by a divide between streams flowing to the Arctic Ocean and those of the Hudson Bay watershed.", "This divide meets the Continental Divide at Snow Dome (also known as Dome), near the northernmost bend of the Columbia River.To the southeast, in western Wyoming, another divide separates the Columbia watershed from the Colorado–Green watershed, which empties into the Gulf of California.", "The Columbia, Colorado, and Mississippi watersheds meet at Three Waters Mountain in the Wind River Range of .", "To the south, in Oregon, Nevada, Utah, Idaho, and Wyoming, the Columbia watershed is divided from the Great Basin, whose several watersheds are endorheic, not emptying into any ocean but rather drying up or sinking into sumps.", "Great Basin watersheds that share a border with the Columbia watershed include Harney Basin, Humboldt River, and Great Salt Lake.", "The associated triple divide points are Commissary Ridge North, Wyoming, and Sproats Meadow Northwest, Oregon.", "To the north, mostly in British Columbia, the Columbia watershed borders the Fraser River watershed.", "To the west and southwest the Columbia watershed borders a number of smaller watersheds that drain to the Pacific Ocean, such as the Klamath River in Oregon and California and the Puget Sound Basin in Washington.=== Major tributaries ===The Deschutes River at its confluence with the ColumbiaThe Columbia receives more than 60 significant tributaries.", "The four largest that empty directly into the Columbia (measured either by discharge or by size of watershed) are the Snake River (mostly in Idaho), the Willamette River (in northwest Oregon), the Kootenay River (mostly in British Columbia), and the Pend Oreille River (mostly in northern Washington and Idaho, also known as the lower part of the Clark Fork).", "Each of these four averages more than and drains an area of more than .The Snake is by far the largest tributary.", "Its watershed of is larger than the state of Idaho.", "Its discharge is roughly a third of the Columbia's at the rivers' confluence but compared to the Columbia upstream of the confluence the Snake is longer (113%) and has a larger drainage basin (104%).The Pend Oreille River system (including its main tributaries, the Clark Fork and Flathead rivers) is also similar in size to the Columbia at their confluence.", "Compared to the Columbia River above the two rivers' confluence, the Pend Oreille-Clark-Flathead is nearly as long (about 86%), its basin about three-fourths as large (76%), and its discharge over a third (37%).Brilliant), Sinixt village site at the confluence of the Kootenay and Columbia Rivers|alt=View of an overgrown field with a rotting fencepost in the foreground and a range of hills in the distanceTributaryAverage dischargeDrainage basinft3/sm3/smi2km2Snake RiverWillamette RiverKootenay River (Kootenai)Pend Oreille RiverCowlitz RiverSpokane RiverLewis RiverDeschutes RiverYakima RiverWenatchee RiverOkanogan RiverKettle RiverSandy RiverJohn Day River" ], [ "See also", "* Columbia Park (Kennewick, Washington), a recreational area* Columbia River Estuary* Columbia River Maritime Museum, Astoria, Oregon* Empire Builder, an Amtrak rail line that follows the river from Portland to Pasco, Washington* Estella Mine, an abandoned mine with a view of the Columbia River Valley* Historic Columbia River Highway, a scenic highway on the Oregon side* List of crossings of the Columbia River* List of dams in the Columbia River watershed* List of longest rivers of Canada* List of longest rivers of the United States (by main stem)* List of longest streams of Oregon* Lists of ecoregions in North America and Oregon* Lists of rivers of British Columbia, Oregon, and Washington* Okanagan Trail, a historic trail that followed the Columbia and Okanagan rivers* Robert Gray's Columbia River expedition" ], [ "Notes" ], [ "References", "=== Sources ===* * * * * * * * * * * * * * * * * * * * * * * * * * (see here for full online transcription)* * * * * * * * * * * * * * * * * * * ===Further reading===* White, Richard.", "''The Organic Machine: The Remaking of the Columbia River'' (Hill and Wang, 1996)" ], [ "External links", "* BC Hydro* Bibliography on Water Resources and International Law Peace Palace Library* * * Columbia River US Environmental Protection Agency* Columbia River Gorge National Scenic Area from the US Forest Service* Columbia River Inter-Tribal Fish Commission* * , dating to the 17th century* University of Washington Libraries Digital Collections – Tollman and Canaris Photographs Photographs document the salmon fishing industry on the southern Washington coast and in the lower Columbia River around the year 1897 and offer insights about commercial salmon fishing and the techniques used at the beginning of the 20th century.", "* Virtual World: Columbia River ''National Geographic'' via Internet Archive" ] ]

[ [ "Commelinales" ], [ "Introduction", "'''Commelinales''' is an order of flowering plants.", "It comprises five families: Commelinaceae, Haemodoraceae, Hanguanaceae, Philydraceae, and Pontederiaceae.", "All the families combined contain over 885 species in about 70 genera; the majority of species are in the Commelinaceae.", "Plants in the order share a number of synapomorphies that tie them together, such as a lack of mycorrhizal associations and tapetal raphides.", "Estimates differ as to when the Commelinales evolved, but most suggest an origin and diversification sometime during the mid- to late Cretaceous.", "Depending on the methods used, studies suggest a range of origin between 123 and 73 million years, with diversification occurring within the group 110 to 66 million years ago.", "The order's closest relatives are in the Zingiberales, which includes ginger, bananas, cardamom, and others." ], [ "Taxonomy", "According to the most recent classification scheme, the APG IV of 2016, the order includes five families:* Commelinaceae* Haemodoraceae* Hanguanaceae* Philydraceae* PontederiaceaeThis is unchanged from the APG III of 2009 and the APG II of 2003, but different from the older APG system of 1998, which did not include Hanguanaceae.=== Previous classification systems ===The older Cronquist system of 1981, which was based purely on morphological data, placed the order in subclass Commelinidae of class Liliopsida and included the families Commelinaceae, Mayacaceae, Rapateaceae and Xyridaceae.", "These families are now known to be only distantly related.In the classification system of Dahlgren the Commelinales were one of four orders in the superorder Commeliniflorae (also called Commelinanae), and contained five families, of which only Commelinaceae has been retained by the Angiosperm Phylogeny Group." ], [ "References", "**" ] ]

[ [ "Cucurbitales" ], [ "Introduction", "The '''Cucurbitales''' are an order of flowering plants, included in the rosid group of dicotyledons.", "This order mostly belongs to tropical areas, with limited presence in subtropical and temperate regions.", "The order includes shrubs and trees, together with many herbs and climbers.", "One major characteristic of the Cucurbitales is the presence of unisexual flowers, mostly pentacyclic, with thick pointed petals (whenever present).", "The pollination is usually performed by insects, but wind pollination is also present (in Coriariaceae and Datiscaceae).The order consists of roughly 2600 species in eight families.", "The largest families are Begoniaceae (begonia family) with around 1500 species and Cucurbitaceae (gourd family) with around 900 species.", "These two families include the only economically important plants.", "Specifically, the Cucurbitaceae (gourd family) include some food species, such as squash, pumpkin (both from ''Cucurbita''), watermelon (''Citrullus vulgaris''), and cucumber and melons (''Cucumis'').", "The Begoniaceae are known for their horticultural species, of which there are over 130 with many more varieties." ], [ "Overview", "The Cucurbitales are an order of plants with a cosmopolitan distribution, particularly diverse in the tropics.", "Most are herbs, climber herbs, woody lianas or shrubs but some genera include canopy-forming evergreen lauroid trees.", "Members of the Cucurbitales form an important component of low to montane tropical forest with greater representation in terms of the number of species.", "Although not known with certainty the total number of species in the order, conservative estimates indicate about 2600 species worldwide, distributed in 109 genera.", "Compared to other flowering plant orders, the taxonomy is poorly understood due to their great diversity, difficulty in identification, and limited study.The order Cucurbitales in the eurosid I clade comprises almost 2600 species in 109 or 110 genera in eight families, tropical and temperate, of very different sizes, morphology, and ecology.", "It is a case of divergent evolution.", "In contrast, there is convergent evolution with other groups not related due to ecological or physical drivers toward a similar solution, including analogous structures.Some species are trees that have similar foliage to the true laurels due to convergent evolution.The patterns of speciation in the Cucurbitales are diversified in a high number of species.", "They have a pantropical distribution with centers of diversity in Africa, South America, and Southeast Asia.", "They most likely originated in West Gondwana 67–107 million years ago, so the oldest split could relate to the break-up of Gondwana in the middle Eocene to late Oligocene, 45–24 million years ago.", "The group reached their current distribution by multiple intercontinental dispersal events.", "One factor was product of aridification, other groups responded to favorable climatic periods and expanded across the available habitat, occurring as opportunistic species across wide distribution; other groups diverged over long periods within isolated areas.The Cucurbitales comprise the families: Apodanthaceae, Anisophylleaceae, Begoniaceae, Coriariaceae, Corynocarpaceae, Cucurbitaceae, Tetramelaceae, and Datiscaceae.", "Some of the synapomorphies of the order are: leaves in spiral with secondary veins palmated, calyx or perianth valvate, and the elevated stomatal calyx/perianth bearing separate styles.", "The two whorls are similar in texture.", "''Tetrameles nudiflora'' is a tree of immense proportions of height and width; Tetramelaceae, Anisophylleaceae, and Corynocarpaceae are tall canopy trees in temperate and tropical forests.", "The genus ''Dendrosicyos'', with the only species being the cucumber tree, is adapted to the arid semidesert island of Socotra.", "Deciduous perennial Cucurbitales lose all of their leaves for part of the year depending on variations in rainfall.", "The leaf loss coincides with the dry season in tropical, subtropical and arid regions.", "In temperate or polar climates, the dry season is due to the inability of the plant to absorb water available in the form of ice.", "Apodanthaceae are obligatory endoparasites that only emerge once a year in the form of small flowers that develop into small berries, however taxonomists have not agreed on the exact placement of this family within the Cucurbitales.Over half of the known members of this order belong to the greatly diverse begonia family Begoniaceae, with around 1500 species in two genera.", "Before modern DNA-molecular classifications, some Cucurbitales species were assigned to orders as diverse as Ranunculales, Malpighiales, Violales, and Rafflesiales.", "Early molecular studies revealed several surprises, such as the nonmonophyly of the traditional Datiscaceae, including ''Tetrameles'' and ''Octomeles'', but the exact relationships among the families remain unclear.The lack of knowledge about the order in general is due to many species being found in countries with limited economic means or unstable political environments, factors unsuitable for plant collection and detailed study.", "Thus the vast majority of species remain poorly determined, and a future increase in the number of species is expected." ], [ "Classification", "Under the Cronquist system, the families Begoniaceae, Cucurbitaceae, and Datiscaceae were placed in the order Violales, within the subclass Dilleniidae, with the Tetramelaceae subsumed into the Datiscaceae.", "Corynocarpaceae was placed in order Celastrales, and Anisophylleaceae in order Rosales, both under subclass Rosidae.", "Coriariaceae was placed in Ranunculaceae, subclass Magnoliidae.", "Apodanthaceae was not recognised as a family, its genera being assigned to another parasitic plant family, the Rafflesiaceae.", "The present classification is due to APG III (2009)." ], [ "Systematics", "Modern molecular phylogenetics suggest the following relationships:" ], [ "References" ], [ "Further reading", "* *" ], [ "External links" ] ]

[ [ "Contra dance" ], [ "Introduction", "Contra dancers at the 2019 Flurry Festival'''Contra dance''' (also '''contradance''', '''contra-dance''' and other variant spellings) is a form of folk dancing made up of long lines of couples.", "It has mixed origins from English country dance, Scottish country dance, and French dance styles in the 17th century.", "Sometimes described as New England folk dance or Appalachian folk dance, contra dances can be found around the world, but are most common in the United States (periodically held in nearly every state), Canada, and other Anglophone countries.A contra dance event is a social dance that one can attend without a partner.", "The dancers form couples, and the couples form sets of two couples in long lines starting from the stage and going down the length of the dance hall.", "Throughout the course of a dance, couples progress up and down these lines, dancing with each other couple in the line.", "The dance is led by a caller who teaches the sequence of moves, called \"figures,\" in the dance before the music starts.", "In a single dance, a caller may include anywhere from six to twelve figures, which are repeated as couples progress up and down the lines.", "Each time through the dance takes 64 beats, after which the pattern is repeated.", "The essence of the dance is in following the pattern with your set and your line; since there is no required footwork, many people find contra dance easier to learn than other forms of social dancing.Musicians play for a contra dance at the John C. Campbell Folk School in Brasstown, North Carolina.Almost all contra dances are danced to live music.", "The music played includes, but is not limited to, Irish, Scottish, old-time, bluegrass and French-Canadian folk tunes.", "The fiddle is considered the core instrument, though other stringed instruments can be used, such as the guitar, banjo, bass and mandolin, as well as the piano, accordion, flute, clarinet and more.", "Techno contra dances are done to techno music, typically accompanied by DJ lighting.", "Music in a dance can consist of a single tune or a medley of tunes, and key changes during the course of a dance are common.Many callers and bands perform for local contra dances, and some are hired to play for dances around the U.S. and Canada.", "Many dancers travel regionally (or even nationally) to contra dance weekends and week-long contra dance camps, where they can expect to find other dedicated and skilled dancers, callers, and bands." ], [ "History", "Peterborough, New Hampshire, United States (silent video)Contra dance has European origins, and over 100 years of cultural influences from many different sources.At the end of the 17th century, English country dances were taken up by French dance masters.", "The French called these dances ''contredanses'' (which roughly translated by sound \"countrydance\" to \"contredanse\"), as indicated in a 1706 dance book called ''Recueil de Contredances''.", "As time progressed, these dances returned to England and were spread and reinterpreted in the United States, and eventually the French form of the name came to be associated with the American folk dances, where they were alternatively called \"country dances\" or in some parts of New England such as New Hampshire, \"contradances\".Contra dances were fashionable in the United States and were considered one of the most popular social dances across class lines in the late 18th century, though these events were usually referred to as \"country dances\" until the 1780s, when the term contra dance became more common to describe these events.", "In the mid-19th century, group dances started to decline in popularity in favor of quadrilles, lancers, and couple dances such as the waltz and polka.", "By the late 19th century, contras were mostly confined to rural settings.", "This began to change with the square dance revival of the 1920s, pioneered by Henry Ford, founder of the Ford Motor Company, in part as a response in opposition to modern jazz influences in the United States.", "In the 1920s, Ford asked his friend Benjamin Lovett, a dance coordinator in Massachusetts, to come to Michigan to begin a dance program.", "Initially, Lovett could not as he was under contract at a local inn; consequently, Ford bought the property rights to the inn.", "Lovett and Ford initiated a dance program in Dearborn, Michigan that included several folk dances, including contras.", "Ford also published a book titled ''Good Morning: After a Sleep of Twenty-Five Years, Old-Fashioned Dancing Is Being Revived'' in 1926 detailing steps for some contra dances.Caller and musician Dudley Laufman, a significant figure in the contra dance revival of the mid-20th centuryIn the 1930s and 1940s, the popularity of jazz, swing, and big band music caused contra dance to decline in several parts of the US; the tradition carried on primarily in towns within the northeastern portions of North America, such as Ohio, the Maritime provinces of Canada, and particularly in New England.", "Ralph Page almost single-handedly maintained the New England tradition until it was revitalized in the 1950s and 1960s, particularly by Ted Sannella and Dudley Laufman.The New England contra dance tradition was also maintained in Vermont by the Ed Larkin Old Time Contra Dancers, formed by Edwin Loyal Larkin in 1934.The group Larkin founded is still performing, teaching the dances, and holding monthly open house dances in Tunbridge, Vermont.By then, early dance camps, retreats, and weekends had emerged, such as Pinewoods Camp, in Plymouth, Massachusetts, which became primarily a music and dance camp in 1933, and NEFFA, the New England Folk Festival, also in Massachusetts, which began in 1944.Pittsburgh Contra Dance celebrated its 100th anniversary in 2015.These and others continue to be popular and some offer other dances and activities besides contra dancing.A BIDA contra dance in Cambridge, Massachusetts, during the COVID-19 pandemicIn the 1970s, Sannella and other callers introduced dance moves from English Country Dance, such as heys and gypsies, to the contra dances.", "New dances, such as ''Shadrack's Delight'' by Tony Parkes, featured symmetrical dancing by all couples.", "(Previously, the actives and inactives – see Progression – had significantly different roles).", "Double progression dances, popularized by Herbie Gaudreau, added to the aerobic nature of the dances, and one caller, Gene Hubert, wrote a quadruple progression dance, ''Contra Madness''.", "Becket formation was introduced, with partners starting the dance next to each other in the line instead of opposite each other.", "The Brattleboro Dawn Dance started in 1976, and continues to run semiannually.In the early 1980s, Tod Whittemore started the first Saturday dance in the Peterborough Town House, which remains one of the more popular regional dances.", "The Peterborough dance influenced Bob McQuillen, who became a notable musician in New England.", "As musicians and callers moved to other locations, they founded contra dances in Michigan, Washington, Oregon, California, Texas, and elsewhere." ], [ "Events", "Glen Echo Park in the suburbs of Washington, D.C.Contra dances take place in more than 200 cities and towns across the U.S. (), as well as other countries.Contra dance events are open to all, regardless of experience, unless explicitly labeled otherwise.", "It is common to see dancers with a wide range of ages, from children to the elderly.", "Contra dances are family-friendly, and alcohol consumption is not part of the culture.", "Many events offer beginner-level instructions prior to the dance.", "A typical evening of contra dance is three hours long, including an intermission.", "The event consists of a number of individual ''contra dances'', each lasting about 15 minutes, and typically a band intermission with some waltzes, schottisches, polkas, or Swedish hambos.", "In some places, square dances are thrown into the mix, sometimes at the discretion of the caller.", "Music for the evening is typically performed by a live band, playing jigs and reels from Ireland, Scotland, Canada, or the USA.", "The tunes may range from traditional originating a century ago, to modern compositions including electric guitar, synth keyboard, and driving percussion – so long as the music fits the timing for contra dance patterns.", "Sometimes, a rock tune will be woven in.Generally, a leader, known as a caller, will teach each individual dance just before the music for that dance begins.", "During this introductory walk-through, participants learn the dance by walking through the steps and formations, following the caller's instructions.", "The caller gives the instructions orally, and sometimes augments them with demonstrations of steps by experienced dancers in the group.", "The walk-through usually proceeds in the order of the moves as they will be done with the music; in some dances, the caller may vary the order of moves during the dance, a fact that is usually explained as part of the caller's instructions.After the walk-through, the music begins and the dancers repeat that sequence some number of times before that dance ends, often 10 to 15 minutes, depending on the length of the contra lines.", "Calls are normally given at least the first few times through, and often for the last.", "At the end of each dance, the dancers thank their partners.", "The contra dance tradition in North America is to change partners for every dance, while in the United Kingdom typically people dance with the same partner the entire evening.", "One who attends an evening of contra dances in North America does not need to bring his or her own partner.", "In the short break between individual dances, the dancers invite each other to dance.", "Booking ahead by asking partner or partners ahead of time for each individual dance is common at some venues, but has been discouraged by some.A pandemic era New Year's Eve contra dance in Greenfield, MassachusettsMost contra dances do not have an expected dress code.", "No special outfits are worn, but comfortable and loose-fitting clothing that does not restrict movement is usually recommended.", "Women usually wear skirts or dresses as they are cooler than wearing trousers; some men also dance in kilts or skirts.", "Low heeled, broken-in, soft-soled, non-marking shoes, such as dance shoes, sneakers, or sandals, are recommended and, in some places, required.", "As dancing can be aerobic, dancers are sometimes encouraged to bring a change of clothes.As in any social dance, cooperation is vital to contra dancing.", "Since over the course of any single dance, individuals interact with not just their partners but everyone else in the set, contra dancing might be considered a group activity.", "As will necessarily be the case when beginners are welcomed in by more practiced dancers, mistakes are made; most dancers are willing to help beginners in learning the steps.", "However, because the friendly, social nature of the dances can be misinterpreted or even abused, some groups have created anti-harassment policies." ], [ "Form", "A contra dance in Manhattan===Formations===Contra dances are arranged in long lines of couples.", "A pair of lines is called a ''set''.", "Sets are generally arranged so they run the length of the hall, with the ''top'' of the set being the end closest to the band and caller, and the ''bottom'' of the set being the end farthest from the caller.Couples consist of two people, traditionally one male and one female, though same-sex pairs are increasingly common.", "Traditionally the dancers are referred to as the ''lady'' and ''gent'', though various other terms have been used: some dances have used ''men'' and ''women'', rejecting ''ladies'' and ''gents'' as elitist; others have used gender-neutral role terms including ''bares'' and ''bands'', ''jets'' and ''rubies'', and ''larks'' and ''ravens'' or ''robins''.", "Couples interact primarily with an adjacent couple for each round of the dance.", "Each sub-group of two interacting couples is known to choreographers as a ''minor set'' and to dancers as a ''foursome'' or ''hands four''.", "Couples in the same minor set are ''neighbors''.", "Minor sets originate at the head of the set, starting with the topmost dancers as the ''ones'' (the ''active couple'' or ''actives''); the other couple are ''twos'' (or ''inactives'').", "The ones are said to be ''above'' their neighboring twos; twos are ''below''.", "If there is an uneven number of couples dancing, the bottom-most couple will wait out the first time through the dance.There are four common ways of arranging couples in the minor sets: ''proper'', ''improper'', ''Becket'', and ''triple'' formations.", "Traditionally, most dances were in the proper formation, with all the gents in one line and all the ladies in the other.", "Until the end of the nineteenth century, minor sets were most commonly triples.", "In the twentieth century, duple-minor dances became more common.", "Since the mid twentieth century, there has been a shift towards improper dances, in which gents and ladies alternate on each side of the set, being the most common formation.", "Triple dances have also lost popularity in modern contras, while Becket formation, in which dancers stand next to their partners, facing another couple, is a modern innovation.===Progression===A fundamental aspect of contra dancing is that, during a single dance, each dancer has one partner, but interacts with many different people.", "During a single dance, the same pattern is repeated over and over (one time through lasts roughly 30 seconds), but each time, a pair of dancers will dance with new neighbors (moving on to new neighbors is called ''progressing'').", "Dancers do not need to memorize these patterns in advance, since the dance leader, or caller, will generally explain the pattern for this dance before the music begins, and give people a chance to walk through the pattern so dancers can learn the moves.", "The walk through also helps dancers understand how the dance pattern leads them toward new people each time.", "Once the music starts, the caller continues to describe each move until the dancers are comfortable with that dance pattern.", "The dance progression is built into the contra dance pattern as continuous motion with the music, and does not interrupt the dancing.", "While all dancers in the room are part of the same dance pattern, half of the couples in the room are moving toward the band at any moment and half are moving away, so when everybody steps forward, they find new people to dance with.", "Once a couple reaches the end of the set, they switch direction, dancing back along the set the other way.A single dance runs around ten minutes, long enough to progress at least 15–20 times.", "If the sets are short to medium length the caller often tries to run the dance until each couple has danced with every other couple both as a one and a two and returned to where they started.", "A typical room of contra dancers may include about 120 people; but this varies from 30 people in smaller towns, to over 300 people in cities like Washington DC, Los Angeles, or New York.", "With longer sets (more than 60 people), one dance typically does not allow dancing with every dancer in the group.==Choreography==Attendees of Youth Dance Weekend 2019 dance \"Dela Says Yippee\" by Dugan Murphy to music by CallunaContra dance choreography specifies the dance formation, the figures, and the sequence of those figures in a dance.", "Contra dance figures (with a few exceptions) do not have defined footwork; within the limits of the music and the comfort of their fellow dancers, individuals move according to their own taste.Most contra dances consist of a sequence of about 6 to 12 individual figures, prompted by the caller in time to the music as the figures are danced.", "As the sequence repeats, the caller may cut down his or her prompting, and eventually drop out, leaving the dancers to each other and the music.A ''figure'' is a pattern of movement that typically takes eight ''counts'', although figures with four or 16 counts are also common.", "Each dance is a collection of figures assembled to allow the dancers to progress along the set (see \"Progression\", above).A ''count'' (as used above) is one half of a musical measure, such as one quarter note in time or three eighth notes in time.", "A count may also be called a ''step'', as contra dance is a walking form, and each count of a dance typically matches a single physical step in a figure.Typical contra dance choreography comprises four ''parts'', each 16 counts (8 measures) long.", "The parts are called A1, A2, B1 and B2.This nomenclature stems from the music: Most contra dance tunes (as written) have two parts (A and B), each 8 measures long, and each fitting one part of the dance.", "The A and B parts are each played twice in a row, hence, A1, A2, B1, B2.While the same music is generally played in, for example, parts A1 and A2, distinct choreography is followed in those parts.", "Thus, a contra dance is typically 64 counts, and goes with a 32 measure tune.", "Tunes of this form are called \"square\"; tunes that deviate from this form are called \"crooked\".Sample contra dances:* Traditional – the actives do most of the movement:''Chorus jig'' (proper duple minor)::A1 (16) Actives down the outside and back.", "(The inactives stand still or substitute a swing).", "::A2 (16) Actives down the center, turn individually, come back, and cast off.", "(The inactives stand still for the first , take a step up the hall, and then participate in the cast).", "::B1 (16) Actives turn contra corners.", "(The inactives participate in half the turns.", ")::B2 (16) Actives meet in the middle for a balance and swing, end swing facing up.", "(The inactives stand still.", ")::''Note:'' inactives will often clog in place or otherwise participate in the dance, even though the figures do not call for them to move.", "* Modern – the dance is symmetrical for actives and inactives:\"Hay in the Barn\" by Chart Guthrie (improper duple minor)::A1 (16) Neighbors balance and swing::A2 (8) Ladies chain across, (8) half hey, ladies pass right shoulders to start.", "::B1 (16) Partners balance and swing.", "::B2 (8) Ladies chain across, (8) half hey, ladies pass right shoulders to start.Many modern contra dances have these characteristics:* longways for as many as will* first couples improper, or Becket formation* flowing choreography* no-one stationary for more than 16 beats (e.g.", "first couple balance and swing, finish facing down to make lines of four)* containing at least one swing and normally both a partner swing and a neighbor swing* the vast majority of the moves from a set of well-known moves that the dancers know already* composed mostly of moves that keep all dancers connected * generally danced to 32 bar jigs or reels played at between 110 and 130 bpm* danced with a smooth walk with many spins and twirlsAn event which consists primarily (or solely) of dances in this style is sometimes referred to as a \"modern urban contra dance\"." ], [ "Music", "Calluna plays Money Musk at Youth Dance Weekend 2019 in Weston, VermontThe most common contra dance repertoire is rooted in the Anglo-Celtic tradition as it developed in North America.", "Irish, Scottish, French Canadian, and Old-time tunes are common, and Klezmer tunes have also been used.", "The old-time repertoire includes very few of the jigs common in the others.Tunes used for a contra dance are nearly always \"square\" 64-beat tunes, in which one time through the tune is each of two 16-beat parts played twice (this is notated AABB).", "However, any 64-beat tune will do; for instance, three 8-beat parts could be played AABB AACC, or two 8-beat parts and one 16-beat part could be played AABB CC.", "Tunes not 64 beats long are called \"crooked\" and are almost never used for contra dancing, although a few crooked dances have been written as novelties.", "Contra tunes are played at a narrow range of tempos, between 108 and 132 bpm.Fiddles are considered to be the primary melody instrument in contra dancing, though other stringed instruments can also be used, such as the mandolin or banjo, in addition to a few wind instruments, for example, the accordion.", "The piano, guitar, and double bass are frequently found in the rhythm section of a contra dance band.", "Occasionally, percussion instruments are also used in contra dancing, such as the Irish bodhran or less frequently, the dumbek or washboard.", "The last few years have seen some of the bands incorporate the Quebecois practice of tapping feet on a board while playing an instrument (often the fiddle).Until the 1970s it was traditional to play a single tune for the duration of a contra dance (about 5 to 10 minutes).", "Since then, contra dance musicians have typically played tunes in sets of two or three related (and sometimes contrasting) tunes, though single-tune dances are again becoming popular with some northeastern bands.", "In the Celtic repertoires it is common to change keys with each tune.", "A set might start with a tune in G, switch to a tune in D, and end with a tune in Bm.", "Here, D is related to G as its dominant (5th), while D and Bm share a key signature of two sharps.", "In the old-time tradition the musicians will either play the same tune for the whole dance, or switch to tunes in the same key.", "This is because the tunings of the five-string banjo are key-specific.", "An old-time band might play a set of tunes in D, then use the time between dances to retune for a set of tunes in A.", "(Fiddlers also may take this opportunity to retune; tune- or key-specific fiddle tunings are uncommon in American Anglo-Celtic traditions other than old-time.", ")In the Celtic repertoires it is most common for bands to play sets of reels and sets of jigs.", "However, since the underlying beat structure of jigs and reels is the same (two \"counts\" per bar) bands will occasionally mix jigs and reels in a set.Some of the most popular contra dance bands in recent years are Great Bear, Perpetual E-Motion, Buddy System, Crowfoot, Elixir, the Mean Lids, Nor'easter, Nova, Pete's Posse, the Stringrays, the Syncopaths, and Wild Asparagus.===Techno contras===A BIDA techno contra dance in Cambridge, Massachusetts, U.S., in 2022In recent years, younger contra dancers have begun establishing \"crossover contra\" or \"techno contra\" – contra dancing to techno, hip-hop, and other modern forms of music.", "While challenging for DJs and callers, the fusion of contra patterns with moves from hip-hop, tango, and other forms of dance has made this form of contra dance a rising trend since 2008.Techno differs from other contra dancing in that it is usually done to recorded music, although there are some bands that play live for techno dances.", "Techno has become especially prevalent in Asheville, North Carolina, but regular techno contra dance series are spreading up the East Coast to locales such as Charlottesville, Virginia; Washington, D.C.; Amherst, Massachusetts; Greenfield, Massachusetts; and various North Carolina dance communities, with one-time or annual events cropping up in locations farther west, including California, Portland, Oregon, and Washington state.", "They also sometimes appear as late night events during contra dance weekends.", "In response to the demand for techno contra, a number of contra dance callers have developed repertoires of recorded songs to play that go well with particular contra dances; these callers are known as DJs.", "A kind of techno/traditional contra fusion has arisen, with at least one band, Buddy System, playing live music melded with synth sounds for techno contra dances." ], [ "See also", "* Ceili dance* Country Dance and Song Society* Dutch crossing* International folk dance* Quadrille" ], [ "Citations" ], [ "General and cited references", "* * See chapter VI, \"Frolics for Fun: Dances, Weddings and Dinner Parties, pages 109 – 124.", "* * * (Reprint: first published in 1956 by American Squares as a part of the ''American Squares Dance Series'')* * * * * * * ** * See chapter entitled \"Country Dancing,\" Pages 57 – 120.", "(The first edition was published in 1939.", ")* * * * * * * *" ], [ "External links", "; Contra dance associations:* Country Dance and Song Society (CDSS) preserves a variety of Anglo-American folk traditions in North America, including folk music, folk song, English country dance, contra dance and morris dance.", ":* Anglo-American Dance Service Based in Belgium, promoting contra dance and English dance in Western Europe.", "; Descriptions & definitions:* Gary Shapiro's What Is Contra Dance?", ":* Hamilton Contra Dances A Contra Dance Primer:* Hamilton Contra Dances Contraculture: An introduction to contradancing:* Sharon Barrett Kennedy's \"Now, What in the World is Contra Dancing?", "\"; Different traditions and cultures in contra dance:* Colin Hume's Advice to Americans in England; Research resources:* University of New Hampshire Special Collections: New Hampshire Library of Traditional Music and Dance ; Finding contra dances:* CDSS Dance Map – interactive, crowd sourced map of contra and folk dances around the world:* Contra Dance Links – comprehensive, up-to-date lists of local dances, weekend dances, musicians, callers, etc.", ":* The Dance Gypsy – locations of contra dances, and many other folk dances, around the world:* Try Contra – Find contra dances using ZIP Code search.", ":* National Contra Grid – Look up dances by day-of-week & City.", ":* ContraDance.org – Description, Links, videos, and local schedule.", ":; In the United Kingdom:* UK Contra Clubs:* Are You Dancing – calendar of social dance events in the UK, including contras:* English Folk Dance and Song Society dance calendar – calendar of folk dance events in the UK, including contras:; In France:* Paris Contra Dance; Video:* Contra dance in Oswego, New York, with music by the Great Bear Trio.", "2013.:* Two American country dance films on DVD: \"Country Corners\" (1976), and \"Full of Life A-Dancin'\" (1978).", ":* Contra dance in Tacoma, Washington, with music by Crowfoot.", "2009.:* Welcome to the Contra Dance – dancers discuss their experiences contra dancing, set over photographs of contras:* The New Contra Dance Commercial (2 minute look at contra in a few dance halls, see playlist):* Why We Contra Dance (dancers discuss why they enjoy contra dance, with video of dancing):* Dancing Community (dancers from Louisville talk about their contra dancing experiences, with video of dancing):* Contra Dancing and New Dancers (new contra dancers in Atlanta, Georgia, discuss their experience):* A History of Contra (documentary of contra dancing, spanning 150+ years of dance culture):* Contra dance in Chattanooga, Tennessee with music by Buddy System and calling by Seth Tepfer, 2019:* The Contra Dance (Doug Plummer's 3 minute slide + video set, with Ed Howe's fiddle music from May 2019):* Contra dance in Glen Echo, Maryland with music by Elixir and calling by Nils Fredland, Contrastock 4, 2014.:* Contra dance in Pinellas, Florida with music by ContraForce and calling by Charlotte Crittenden, 2017):* Example Contra Dance Lesson (caller Cis Hinkle explains the basics, with contra vocabulary):* Contra Nils Walkthrough and Dance" ] ]

[ [ "Coin collecting" ], [ "Introduction", "A coin collection, featuring coins loose and in various storage mediums.", "'''Coin collecting''' is the collecting of coins or other forms of minted legal tender.", "Coins of interest to collectors include beautiful, rare, and historically significant pieces.", "Collectors may be interested, for example, in complete sets of a particular design or denomination, coins that were in circulation for only a brief time, or coins with errors.", "Coin collecting can be differentiated from numismatics, in that the latter is the systematic study of currency as a whole, though the two disciplines are closely interlinked.Many factors determine a coin's value including grade, rarity, and popularity.", "Commercial organizations offer grading services and will grade, authenticate, attribute, and encapsulate most coins." ], [ "History", "''Portrait of a Man with a Roman Medal'' by Hans Memling, depicting a Renaissance collector with a sestertius of NeroPeople have hoarded coins for their bullion value for as long as coins have been minted.", "However, the collection of coins for their artistic value was a later development.", "Evidence from the archaeological and historical record of Ancient Rome and medieval Mesopotamia indicates that coins were collected and catalogued by scholars and state treasuries.", "It also seems probable that individual citizens collected old, exotic or commemorative coins as an affordable, portable form of art.", "According to Suetonius in his ''De vita Caesarum'' (''The Lives of the Twelve Caesars''), written in the first century AD, the emperor Augustus sometimes presented old and exotic coins to friends and courtiers during festivals and other special occasions.", "While the literary sources are scarce, it's evident that collecting of ancient coins persisted in the Western World during the Middle Ages among rulers and high nobility.Contemporary coin collecting and appreciation began around the fourteenth century.", "During the Renaissance, it became a fad among some members of the privileged classes, especially kings and queens.", "The Italian scholar and poet Petrarch is credited with being the pursuit's first and most famous aficionado.", "Following his lead, many European kings, princes, and other nobility kept collections of ancient coins.", "Some notable collectors were Pope Boniface VIII, Emperor Maximilian I of the Holy Roman Empire, Louis XIV of France, Ferdinand I of Spain and Holy Roman Emperor, Henry IV of France and Elector Joachim II of Brandenburg, who started the Berlin Coin Cabinet (German: ''Münzkabinett Berlin'').", "Perhaps because only the very wealthy could afford the pursuit, in Renaissance times coin collecting became known as the \"Hobby of Kings\".During the 17th and 18th centuries coin collecting remained a pursuit of the well-to-do.", "But rational, Enlightenment thinking led to a more systematic approach to accumulation and study.", "Numismatics as an academic discipline emerged in these centuries at the same time as a growing middle class, eager to prove their wealth and sophistication, began to collect coins.", "During the 19th and 20th centuries, coin collecting increased further in popularity.", "The market for coins expanded to include not only antique coins, but foreign or otherwise exotic currency.", "Coin shows, trade associations, and regulatory bodies emerged during these decades.", "The first international convention for coin collectors was held 15–18 August 1962, in Detroit, Michigan, and was sponsored by the American Numismatic Association and the Royal Canadian Numismatic Association.", "Attendance was estimated at 40,000.As one of the oldest and most popular world pastimes, coin collecting is now often referred to as the \"King of Hobbies\"." ], [ "Motivations", "Two 20 kronor gold coins from the ScandinavianMonetary UnionThe motivations for collecting vary.", "Possibly the most common type of collectors are the hobbyists, who amass a collection primarily for the pleasure of it without the intention of making a profit.Another frequent reason for purchasing coins is as an investment.", "As with stamps, precious metals, or other commodities, coin prices vary based on supply and demand.", "Prices drop for coins that are not in long-term demand, and increase along with a coin's perceived or intrinsic value.", "Investors buy with the expectation that the value of their purchase will increase over the long term.", "As with all types of investment, the principle of ''caveat emptor'' applies, and study is recommended before buying.", "Likewise, as with most collectibles, a coin collection does not produce income until it is sold, and may even incur costs (for example, the cost of safe deposit box storage) in the interim.A little collection of precious coins, coin slab, including a vintage sterling silver box, in India.Some people collect coins for patriotic reasons and mints from various countries create coins specifically for patriotic collectors.", "One example of a patriotic coin was minted in 1813 by the United Provinces of the Rio de la Plata.", "One of the first pieces of legislation the new country enacted (after the revolution that freed it from Spanish rule) was to mint coins to replace the Spanish currency that had been in use.", "Another example is the U.S. 2022 Purple Heart Commemorative Coin Program." ], [ "Collector types", "Some coin collectors are generalists and accumulate examples from a broad variety of historical or geographically significant coins, but most collectors focus on a narrower, specialist interest.", "For example, some collectors focus on coins based on a common theme, such as coins from a country (often the collector's own), a coin each year from a series, or coins with a common mint mark.There are also completists who seek an example of every type of coin within a certain category.", "One of the most famous of this type of collector is Louis E. Eliasberg, the only collector thus far to assemble a complete set of known coins of the United States.Foreign coin collecting is another type of collection that numismatics enjoy collecting.Coin hoarders are similar to investors in the sense that they accumulate coins for potential long-term profit.", "However, they typically do not take into account aesthetic considerations.", "This is most common with coins whose metal value exceeds their spending value.Modern-day coins are a popular and important part of coin collecting.Speculators, be they amateurs or commercial buyers, may purchase coins in bulk or in small batches, and often act with the expectation of delayed profit.", "They may wish to take advantage of a spike in demand for a particular coin (for example, during the annual release of Canadian numismatic collectibles from the Royal Canadian Mint).", "The speculator might hope to buy the coin in large lots and sell at a profit within weeks or months.", "Speculators may also buy common circulation coins for their intrinsic metal value.", "Coins without collectible value may be melted down or distributed as bullion for commercial purposes.", "Typically they purchase coins that are composed of rare or precious metals, or coins that have a high purity of a specific metal.A final type of collector is the inheritor, an accidental collector who acquires coins from another person as part of an inheritance.", "The inheritor type may not necessarily have an interest in or know anything about numismatics at the time of the acquisition.PCGS graded silver coin" ], [ "Grade and value", "This Deutsche Mark coin shows blemishes and rim dents that would detract from its grade in appraisal.", "In coin collecting, the condition of a coin (its grade) is key to its value; a high-quality example with minimal wear is often worth many times more than a poor example.", "Collectors have created systems to describe the overall condition of coins.", "Any damage, such as wear or cleaning, can substantially decrease a coin's value.By the mid 20th century, with the growing market for rare coins, the American Numismatic Association helps identify most coins in North America, numbering coins from 1 (poor) to 70 (mint state), and setting aside a separate category for proof coinage.", "This system is often shunned by coin experts in Europe and elsewhere, who prefer to use adjectival grades.", "Nevertheless, most grading systems use similar terminology, and values and remain mutually intelligible." ], [ "Certification services", "Third-party grading (TPG), aka ''coin certification services'', emerged in the 1980s with the goals of standardizing grading, exposing alterations, and eliminating counterfeits.", "For tiered fees, certification services grade, authenticate, attribute, and encapsulate coins in clear plastic holders.Coin certification has greatly reduced the number of counterfeits and grossly over graded coins, and improved buyer confidence.", "Certification services can sometimes be controversial because grading is subjective; coins may be graded differently by different services or even upon resubmission to the same service.", "The numeric grade alone does not represent all of a coin's characteristics, such as toning, strike, brightness, color, luster, and attractiveness.", "Due to potentially large differences in value over slight differences in a coin's condition, some submitters will repeatedly resubmit a coin to a grading service in the hope of receiving a higher grade.", "Because fees are charged for certification, submitters must funnel money away from purchasing additional coins." ], [ "Clubs", "Coin collectors and enthusiasts enjoying the taste of numismatic items at an exhibition organized by the Numismatic Society of Calcutta, in Ballygunge, Kolkata, West Bengal.Coin collector clubs offer a variety of benefits to members.", "They usually serve as a source of information and unification of people interested in coins.", "Collector clubs are popular both offline and online." ], [ "See also", "* Challenge coin* Coin* Coin catalog* Coin grading* Coin slab* Commemorative coin* Exonumia* Numismatics* Regular issue coinage* Seigniorage* List of most expensive coins===Examples===* Byron Reed Collection* Collection at Ibn Sina Academy" ], [ "References" ] ]

[ [ "Crokinole" ], [ "Introduction", "'''Crokinole''' ( ) is a disk-flicking dexterity board game, possibly of Canadian origin, similar to the games of pitchnut, carrom, and pichenotte, with elements of shuffleboard and curling reduced to table-top size.", "Players take turns shooting discs across the circular playing surface, trying to land their discs in the higher-scoring regions of the board, particularly the recessed centre hole of 20 points, while also attempting to knock opposing discs off the board, and into the 'ditch'.", "In crokinole, the shooting is generally towards the centre of the board, unlike carroms and pitchnut, where the shooting is towards the four outer corner pockets, as in pool.", "Crokinole is also played using cue sticks, and there is a special category for cue stick participants at the World Crokinole Championships in Tavistock, Ontario, Canada." ], [ "Equipment", "A round tournament style crokinole board.", "Boards may also be octagonal, which is the more traditional shape.Board dimensions vary with a playing surface typically of polished wood or laminate approximately in diameter.", "The arrangement is 3 concentric rings worth 5, 10, and 15 points as you move in from the outside.", "There is a shallow 20-point hole at the centre.", "The inner 15-point ring is guarded with 8 small bumpers or posts.", "The outer ring of the board is divided into four quadrants.", "The outer edge of the board is raised slightly to keep errant shots from flying out, with a gutter between the playing surface and the edge to collect discarded pieces.", "Crokinole boards are typically octagonal or round in shape.", "The wooden discs are roughly checker-sized, slightly smaller in diameter than the board's central hole, and typically have one side slightly concave and one side slightly convex, mainly due to the inherent features of wood, more than a planned design.", "Alternatively, the game may be played with ring-shaped pieces with a central hole.===Powder===The use of any lubricating powder in crokinole is controversial, with some purists reviling the practice.Powder is sometimes used to ensure pieces slide smoothly on the surface.", "Boric acid was popular for a long time, but is now considered toxic and has been replaced with safer substitutes.", "The EU has classified Boric acid as a \"Serious Health Hazard\".", "In the UK, many players use a version of anti-set-off spray powder, from the printing industry, which has specific electrostatic properties, with particles of 50-micrometre diameter ().", "The powder is made of pure food-grade plant/vegetable starch.The World Crokinole Championships in Tavistock, Ontario, Canada, states: \"The WCC waxes boards, as required, with paste wax.", "On tournament day powdered shuffleboard wax (CAPO fast speed, yellow and white container) is placed in the ditch.", "Only tournament organizers will apply quality granular shuffleboard wax.", "Wax will be placed in the ditch area so that players can rub their discs in the wax prior to shooting, if they desire.", "Contestants are not allowed to apply lubricants of any type to the board.", "Absolutely no other lubricant will be allowed\"." ], [ "Gameplay", "Crokinole is most commonly played by two players, or by four players in teams of two, with partners sitting across the board from each other.", "Players take turns flicking their discs from the outer edge of their quadrant of the board onto the playfield.", "Shooting is usually done by flicking the disc with a finger, though sometimes small cue sticks may be used.", "If there are any enemy discs on the board, a player must make contact, directly or indirectly, with an enemy disc during the shot.", "If unsuccessful, the shot disc is \"fouled\" and removed from the board, along with any of the player's other discs that were moved during the shot.When there are no enemy discs on the board, many (but not all) rules also state that a player must shoot for the centre of the board, and a shot disc must finish either completely inside the 15-point guarded ring line, or (depending on the specifics of the rules) be inside or touching this line.", "This is often called the \"no hiding\" rule, since it prevents players from placing their first shots where their opponent must traverse completely through the guarded centre ring to hit them and avoid fouling.", "When playing without this rule, a player may generally make any shot desired, and as long as a disc remains completely inside the outer line of the playfield, it remains on the board.", "During any shot, any disc that falls completely into the recessed central \"20\" hole (a.k.a.", "the \"Toad\" or \"Dukie\") is removed from play, and counts as twenty points for the owner of the disc at the end of the round, assuming the shot is valid.Crokinole game board scoring zonesScoring occurs after all pieces (generally 12 per player or team) have been played, and is differential: i.e., the player or team with higher score is awarded the difference between the higher and lower scores for the round, thus only one team or player each round gains points.", "Play continues until a predetermined winning score is reached." ], [ "History of the game", "Crokinole board by M.B.", "Ross, patented 1880After 30 years of research, Wayne Kelly published his assessment of the first origins of crokinole, in ''The Crokinole Book'', Third Edition, page 28, which leaves the door open to future research and discovery of the origins of the game of crokinole: \"The earliest American crokinole board and reference to the game is M. B. Ross's patented New York board of 1880.The earliest Canadian reference is 1867 (''Sports and Games in Canadian Life: 1700 to the Present'' by Howell and Howell, Toronto, MacMillan Company of Canada, 1969, p.61), and the oldest piece dated at 1875 by Ekhardt Wettlaufer.", "Could Ekhardt Wettlaufer have visited friends in New York state, noticed an unusual and entertaining parlour game being played, and upon arrival at home, made an imitation as a gift for his son?", "After all, he was a talented, and no doubt resourceful, painter and woodworker.", "Or was it the other way around?", "Did Mr. M. B. Ross travel to Ontario, take note of a quaint piece of rural folk art, and upon return to New York, put his American entrepreneurial skills to work - complete with patent name - on his new crokinole board?", "As the trail is more than 100 years old and no other authoritative source can be found, it appears, at the moment, that Eckhardt Wettlaufer or M. B. Ross are as close as we can get to answering the question WHO (made the first crokinole board.", ")\"The earliest known crokinole board was made by craftsman Eckhardt Wettlaufer in 1876 in Perth County, Ontario, Canada.", "It is said Wettlaufer crafted the board as a fifth birthday present for his son Adam, which is now part of the collection at the Joseph Schneider Haus, a national historic site in Kitchener, Ontario, with a focus on Germanic folk art.", "Several other home-made boards dating from southwestern Ontario in the 1870s have been discovered since the 1990s.", "A board game similar to crokinole was patented on 20 April 1880 by Joshua K. Ingalls (US Patent No.", "226,615)Crokinole is often believed to be of Mennonite or Amish origins, but there is no factual data to support such a claim.", "The reason for this misconception may be due to its popularity in Mennonite and Amish groups.", "The game was viewed as a rather innocuous pastime – unlike the perception that diversions such as card playing or dancing were considered \"works of the Devil\" as held by many 19th-century Protestant groups.The oldest roots of crokinole, from the 1860s, suggest the British and South Asian games, such as carrom, are the most likely antecedents of what became crokinole.Crokinole board by M.B.", "Ross, patented 1880In 2006, a documentary film called ''Crokinole'' was released.", "The world premiere occurred at the Princess Cinema in Waterloo, Ontario, in early 2006.The movie follows some of the competitors of the 2004 World Crokinole Championship as they prepare for the event." ], [ "Origins of the name", "The name \"crokinole\" derives from , a French word today designating:#in France, a kind of cookie (or biscuit in British English), similar to a ''biscotto'';#in French Canada, a pastry somewhat similar to a doughnut (except for the shape).It also used to designate the action of flicking with the finger (Molière, ''Le malade imaginaire''; or Voltaire, ''Lettre à Frédéric II Roi de Prusse''; etc.", "), and this seems the most likely origin of the name of the game.", "was also a synonym of , a word that gave its name to the different but related games of pichenotte and pitchnut.From The Crokinole Book 3rd Edition by Wayne S. Kelly \"Is it possible that the English word 'crokinole' is simply an etymological offspring of the French word 'croquignole'?", "It would appear so for the following reasons.", "Going back to the entry for Crokinole in Webster's Third New International Dictionary, within the etymological brackets, it says: French croquignole, fillip.", "This is a major clue.", "The word fillip, according to Webster's, has two definitions: \"1.a blow or gesture made by the sudden forcible release of a finger curled up against the thumb; a short sharp blow.", "2.to strike by holding the nail of a finger curled up against the ball of the thumb and then suddenly releasing it from that position\".", "So it seems evident, then, that our game of crokinole derives its name from the verb form (of croquignole) defining the principle action in the game, that of flicking or 'filliping' a playing piece across the board\".The word Crokinole is generally acknowledged to have been derived from the French Canadian word \"Croquignole\", a word with several meanings, such as fillip, snap, biscuit, bun and a woman's wavy hairstyle popular at the turn of the century.", "The US state of New York shares border crossings with both of the Canadian provinces of Ontario and Quebec, all three of which are popular \"hotbeds\" of Crokinole playing.Crokinole is called ('flick-board') (and occasionally ''knipsdesh'' (flick-table)) in the Plautdietsch spoken by Russian Mennonites." ], [ "World Crokinole Championship", "World Crokinole Championship 1999, in Tavistock, Ontario, CanadaThe World Crokinole Championship (WCC) tournament has been held annually since 1999 on the first Saturday of June in Tavistock, Ontario.", "Tavistock was chosen as the host city because it was the home of Eckhardt Wettlaufer, the maker of the earliest known board.", "The tournament has seen registration from every Canadian province, several American states, Germany, Australia, Spain and the UK.The WCC singles competition begins with a qualifying round in which competitors play 10 matches against randomly assigned opponents.", "The qualifying round is played in a large randomly determined competition.", "At the end of the opening round, the top 16 competitors move on to the playoffs.", "The top four in the playoffs advance to a final round robin to play each other, and the top two compete in the finals.", "The WCC doubles competition begins with a qualifying round of 8 matches against randomly assigned opponents with the top six teams advancing to a playoff round robin to determine the champions.The WCC has multiple divisions, including a singles finger-shooting category for competitive players (adult singles), novices (recreational), and younger players (intermediate, 11–14 yrs; junior, 6–10 yrs), as well as a division for cue-shooters (cues singles).", "The WCC also awards a prize for the top 20-hole shooter in the qualifying round of competitive singles, recreational singles, cues singles, intermediate singles, and in the junior singles.", "The tournament also holds doubles divisions for competitive fingers-shooting (competitive doubles), novices (recreational doubles), younger players (youth doubles, 6–16yrs), and cues-shooting (cues doubles).World Crokinole Championship 1999The official board builder of the World Crokinole Championships is Jeremy Tracey." ], [ "National Crokinole Association", "The National Crokinole Association (NCA) is an association that supports existing, and the development of new, crokinole clubs and tournaments.", "While the majority of NCA events are based in Ontario, Canada, the NCA has held sanctioned events in the Canadian provinces of PEI and BC, as well as in New York State.The collection of NCA tournaments is referred to as the NCA Tour.", "Each NCA Tour season begins at the Tavistock World Crokinole Championships in June, and concludes at the Ontario Singles Crokinole Championship in May of the following years.", "The results of each tournament award points for each player, as they compete for their season-ending ranking classification." ], [ "See also", "*Chapayev*Novuss*Pichenotte*Table shuffleboard" ], [ "References" ], [ "External links", "* Crokinole FAQ by Wayne and Caleb Kelly * * World Crokinole Championships in Tavistock, Ontario* National Crokinole Association* The Crokinole Post* Crokinole Skills Competition Videos* Our Canada Magazine Article about Crokinole* Crokinole Friends of the Pichenotte Guys* Crokinole Canada by Ted Fuller* Crokinole Game Boards by Jeremy Tracey* The Crokinole Depot by The Beierling Brothers" ] ]

[ [ "Capitalism" ], [ "Introduction", "'''Capitalism''' is an economic system based on the private ownership of the means of production and their operation for profit.", "Central characteristics of capitalism include capital accumulation, competitive markets, price systems, private property, property rights recognition, voluntary exchange, and wage labor.", "In a market economy, decision-making and investments are determined by owners of wealth, property, or ability to maneuver capital or production ability in capital and financial markets—whereas prices and the distribution of goods and services are mainly determined by competition in goods and services markets.Economists, historians, political economists, and sociologists have adopted different perspectives in their analyses of capitalism and have recognized various forms of it in practice.", "These include ''laissez-faire'' or free-market capitalism, anarcho-capitalism, state capitalism, and welfare capitalism.", "Different forms of capitalism feature varying degrees of free markets, public ownership, obstacles to free competition, and state-sanctioned social policies.", "The degree of competition in markets and the role of intervention and regulation, as well as the scope of state ownership, vary across different models of capitalism.", "The extent to which different markets are free and the rules defining private property are matters of politics and policy.", "Most of the existing capitalist economies are mixed economies that combine elements of free markets with state intervention and in some cases economic planning.Capitalism in its modern form emerged from agrarianism in 16th century England and mercantilist practices by European countries in the 16th to 18th centuries.", "The Industrial Revolution of the 18th century established capitalism as a dominant mode of production, characterized by factory work and a complex division of labor.", "Through the process of globalization, capitalism spread across the world in the 19th and 20th centuries, especially before World War I and after the end of the Cold War.", "During the 19th century, capitalism was largely unregulated by the state, but became more regulated in the post–World War II period through Keynesianism, followed by a return of more unregulated capitalism starting in the 1980s through neoliberalism.Market economies have existed under many forms of government and in many different times, places and cultures.", "Modern industrial capitalist societies developed in Western Europe in a process that led to the Industrial Revolution.", "Capitalist economies promote economic growth through accumulation of capital, however a business cycle of economic growth followed by recession is a common characteristic of such economies." ], [ "Etymology", "Other terms sometimes used for capitalism:* Capitalist mode of production* Economic liberalism* Free enterprise* Free enterprise economy* Free market* Free market economy* ''Laissez-faire''* Market economy* Profits system* Self-regulating marketThe term \"capitalist\", meaning an owner of capital, appears earlier than the term \"capitalism\" and dates to the mid-17th century.", "\"Capitalism\" is derived from ''capital'', which evolved from , a late Latin word based on , meaning \"head\"—which is also the origin of \"chattel\" and \"cattle\" in the sense of movable property (only much later to refer only to livestock).", "emerged in the 12th to 13th centuries to refer to funds, stock of merchandise, sum of money or money carrying interest.", "By 1283, it was used in the sense of the capital assets of a trading firm and was often interchanged with other words—wealth, money, funds, goods, assets, property and so on.The ''Hollantse () Mercurius'' uses \"capitalists\" in 1633 and 1654 to refer to owners of capital.", "In French, Étienne Clavier referred to ''capitalistes'' in 1788, four years before its first recorded English usage by Arthur Young in his work ''Travels in France'' (1792).", "In his ''Principles of Political Economy and Taxation'' (1817), David Ricardo referred to \"the capitalist\" many times.", "English poet Samuel Taylor Coleridge used \"capitalist\" in his work ''Table Talk'' (1823).", "Pierre-Joseph Proudhon used the term in his first work, ''What is Property?''", "(1840), to refer to the owners of capital.", "Benjamin Disraeli used the term in his 1845 work ''Sybil''.The initial use of the term \"capitalism\" in its modern sense is attributed to Louis Blanc in 1850 (\"What I call 'capitalism' that is to say the appropriation of capital by some to the exclusion of others\") and Pierre-Joseph Proudhon in 1861 (\"Economic and social regime in which capital, the source of income, does not generally belong to those who make it work through their labor\").", "Karl Marx frequently referred to the \"capital\" and to the \"capitalist mode of production\" in ''Das Kapital'' (1867).", "Marx did not use the form ''capitalism'' but instead used capital, ''capitalist'' and ''capitalist mode of production'', which appear frequently.", "Due to the word being coined by socialist critics of capitalism, economist and historian Robert Hessen stated that the term \"capitalism\" itself is a term of disparagement and a misnomer for economic individualism.", "Bernard Harcourt agrees with the statement that the term is a misnomer, adding that it misleadingly suggests that there is such as a thing as \"capital\" that inherently functions in certain ways and is governed by stable economic laws of its own.In the English language, the term \"capitalism\" first appears, according to the ''Oxford English Dictionary'' (OED), in 1854, in the novel ''The Newcomes'' by novelist William Makepeace Thackeray, where the word meant \"having ownership of capital\".", "Also according to the OED, Carl Adolph Douai, a German American socialist and abolitionist, used the term \"private capitalism\" in 1863." ], [ "Definition", "There is no universally agreed upon definition of capitalism; it is unclear whether or not capitalism characterizes an entire society, a specific type of social order, or crucialcomponents or elements of a society.", "Societies officially founded in opposition to capitalism (such as the Soviet Union) have sometimes been argued to actually exhibit characteristics of capitalism.", "Nancy Fraser describes usage of the term \"capitalism\" by many authors as \"mainly rhetorical, functioning less as an actual concept than as a gesture toward theneed for a concept\".", "Scholars who are uncritical of capitalism rarely actually use the term \"capitalism\".", "Some doubt that the term \"capitalism\" possesses valid scientific dignity, and it is generally not discussed in mainstream economics, with economist Daron Acemoglu suggesting that the term \"capitalism\" should be abandoned entirely.", "Consequently, understanding of the concept of capitalism tends to be heavily influenced by opponents of capitalism and by the followers and critics of Karl Marx." ], [ "History", "Cosimo de' Medici, who managed to build an international financial empire and was one of the first Medici bankersAugsburg, early centre of capitalismCapitalism, in its modern form, can be traced to the emergence of agrarian capitalism and mercantilism in the early Renaissance, in city-states like Florence.", "Capital has existed incipiently on a small scale for centuries in the form of merchant, renting and lending activities and occasionally as small-scale industry with some wage labor.", "Simple commodity exchange and consequently simple commodity production, which is the initial basis for the growth of capital from trade, have a very long history.", "During the Islamic Golden Age, Arabs promulgated capitalist economic policies such as free trade and banking.", "Their use of Indo-Arabic numerals facilitated bookkeeping.", "These innovations migrated to Europe through trade partners in cities such as Venice and Pisa.", "Italian mathematicians traveled the Mediterranean talking to Arab traders and returned to popularize the use of Indo-Arabic numerals in Europe.=== Agrarianism ===The economic foundations of the feudal agricultural system began to shift substantially in 16th-century England as the manorial system had broken down and land began to become concentrated in the hands of fewer landlords with increasingly large estates.", "Instead of a serf-based system of labor, workers were increasingly employed as part of a broader and expanding money-based economy.", "The system put pressure on both landlords and tenants to increase the productivity of agriculture to make profit; the weakened coercive power of the aristocracy to extract peasant surpluses encouraged them to try better methods, and the tenants also had incentive to improve their methods in order to flourish in a competitive labor market.", "Terms of rent for land were becoming subject to economic market forces rather than to the previous stagnant system of custom and feudal obligation.=== Mercantilism ===A painting of a French seaport from 1638 at the height of mercantilismThe economic doctrine prevailing from the 16th to the 18th centuries is commonly called mercantilism.", "This period, the Age of Discovery, was associated with the geographic exploration of foreign lands by merchant traders, especially from England and the Low Countries.", "Mercantilism was a system of trade for profit, although commodities were still largely produced by non-capitalist methods.", "Most scholars consider the era of merchant capitalism and mercantilism as the origin of modern capitalism, although Karl Polanyi argued that the hallmark of capitalism is the establishment of generalized markets for what he called the \"fictitious commodities\", i.e.", "land, labor and money.", "Accordingly, he argued that \"not until 1834 was a competitive labor market established in England, hence industrial capitalism as a social system cannot be said to have existed before that date\".Robert Clive with the Nawabs of Bengal after the Battle of Plassey which began the British rule in IndiaEngland began a large-scale and integrative approach to mercantilism during the Elizabethan Era (1558–1603).", "A systematic and coherent explanation of balance of trade was made public through Thomas Mun's argument ''England's Treasure by Forraign Trade, or the Balance of our Forraign Trade is The Rule of Our Treasure.''", "It was written in the 1620s and published in 1664.European merchants, backed by state controls, subsidies and monopolies, made most of their profits by buying and selling goods.", "In the words of Francis Bacon, the purpose of mercantilism was \"the opening and well-balancing of trade; the cherishing of manufacturers; the banishing of idleness; the repressing of waste and excess by sumptuary laws; the improvement and husbanding of the soil; the regulation of prices...\".After the period of the proto-industrialization, the British East India Company and the Dutch East India Company, after massive contributions from the Mughal Bengal, inaugurated an expansive era of commerce and trade.", "These companies were characterized by their colonial and expansionary powers given to them by nation-states.", "During this era, merchants, who had traded under the previous stage of mercantilism, invested capital in the East India Companies and other colonies, seeking a return on investment.=== Industrial Revolution ===The Watt steam engine, a steam engine fuelled primarily by coal propelled the Industrial Revolution in Great BritainIn the mid-18th century a group of economic theorists, led by David Hume (1711–1776) and Adam Smith (1723–1790), challenged fundamental mercantilist doctrines—such as the belief that the world's wealth remained constant and that a state could only increase its wealth at the expense of another state.During the Industrial Revolution, industrialists replaced merchants as a dominant factor in the capitalist system and effected the decline of the traditional handicraft skills of artisans, guilds and journeymen.", "Industrial capitalism marked the development of the factory system of manufacturing, characterized by a complex division of labor between and within work process and the routine of work tasks; and eventually established the domination of the capitalist mode of production.Industrial Britain eventually abandoned the protectionist policy formerly prescribed by mercantilism.", "In the 19th century, Richard Cobden (1804–1865) and John Bright (1811–1889), who based their beliefs on the Manchester School, initiated a movement to lower tariffs.", "In the 1840s Britain adopted a less protectionist policy, with the 1846 repeal of the Corn Laws and the 1849 repeal of the Navigation Acts.", "Britain reduced tariffs and quotas, in line with David Ricardo's advocacy of free trade.=== Modernity ===The gold standard formed the financial basis of the international economy from 1870 to 1914.Broader processes of globalization carried capitalism across the world.", "By the beginning of the nineteenth century, a series of loosely connected market systems had come together as a relatively integrated global system, in turn intensifying processes of economic and other globalization.", "Late in the 20th century, capitalism overcame a challenge by centrally-planned economies and is now the encompassing system worldwide, with the mixed economy as its dominant form in the industrialized Western world.Industrialization allowed cheap production of household items using economies of scale, while rapid population growth created sustained demand for commodities.", "The imperialism of the 18th-century decisively shaped globalization.After the First and Second Opium Wars (1839–60) and the completion of the British conquest of India by 1858, vast populations of Asia became consumers of European exports.", "Europeans colonized areas of sub-Saharan Africa and the Pacific islands.", "Colonisation by Europeans, notably of sub-Saharan Africa, yielded valuable natural resources such as rubber, diamonds and coal and helped fuel trade and investment between the European imperial powers, their colonies and the United States:From the 1870s to the early 1920s, the global financial system was mainly tied to the gold standard.", "The United Kingdom first formally adopted this standard in 1821.Soon to follow were Canada in 1853, Newfoundland in 1865, the United States and Germany (''de jure'') in 1873.New technologies, such as the telegraph, the transatlantic cable, the radiotelephone, the steamship and railways allowed goods and information to move around the world to an unprecedented degree.In the United States, the term \"capitalist\" primarily referred to powerful businessmen until the 1920s due to widespread societal skepticism and criticism of capitalism and its most ardent supporters.The New York stock exchange traders' floor (1963)Contemporary capitalist societies developed in the West from 1950 to the present and this type of system continues throughout the world—relevant examples started in the United States after the 1950s, France after the 1960s, Spain after the 1970s, Poland after 2015, and others.", "At this stage most capitalist markets are considered developed and characterized by developed private and public markets for equity and debt, a high standard of living (as characterized by the World Bank and the IMF), large institutional investors and a well-funded banking system.", "A significant managerial class has emerged and decides on a significant proportion of investments and other decisions.", "A different future than that envisioned by Marx has started to emerge—explored and described by Anthony Crosland in the United Kingdom in his 1956 book ''The Future of Socialism'' and by John Kenneth Galbraith in North America in his 1958 book ''The Affluent Society'', 90 years after Marx's research on the state of capitalism in 1867.The postwar boom ended in the late 1960s and early 1970s and the economic situation grew worse with the rise of stagflation.", "Monetarism, a modification of Keynesianism that is more compatible with ''laissez-faire'' analyses, gained increasing prominence in the capitalist world, especially under the years in office of Ronald Reagan in the United States (1981–1989) and of Margaret Thatcher in the United Kingdom (1979–1990).", "Public and political interest began shifting away from the so-called collectivist concerns of Keynes's managed capitalism to a focus on individual choice, called \"remarketized capitalism\".The end of the Cold War and the dissolution of the Soviet Union allowed for capitalism to become a truly global system in a way not seen since before World War I.", "The development of the neoliberal global economy would have been impossible without the fall of communism.Harvard Kennedy School economist Dani Rodrik distinguishes between three historical variants of capitalism:* Capitalism 1.0 during the 19th century entailed largely unregulated markets with a minimal role for the state (aside from national defense, and protecting property rights)* Capitalism 2.0 during the post-World War II years entailed Keynesianism, a substantial role for the state in regulating markets, and strong welfare states* Capitalism 2.1 entailed a combination of unregulated markets, globalization, and various national obligations by states==== Relationship to democracy ====The relationship between democracy and capitalism is a contentious area in theory and in popular political movements.", "The extension of adult-male suffrage in 19th-century Britain occurred along with the development of industrial capitalism and representative democracy became widespread at the same time as capitalism, leading capitalists to posit a causal or mutual relationship between them.", "However, according to some authors in the 20th-century, capitalism also accompanied a variety of political formations quite distinct from liberal democracies, including fascist regimes, absolute monarchies and single-party states.", "Democratic peace theory asserts that democracies seldom fight other democracies, but others suggest this may be because of political similarity or stability, rather than because they are \"democratic\" or \"capitalist\".", "Critics argue that though economic growth under capitalism has led to democracy, it may not do so in the future as authoritarian régimes have been able to manage economic growth using some of capitalism's competitive principles without making concessions to greater political freedom.Political scientists Torben Iversen and David Soskice see democracy and capitalism as mutually supportive.", "Robert Dahl argued in ''On Democracy'' that capitalism was beneficial for democracy because economic growth and a large middle class were good for democracy.", "He also argued that a market economy provided a substitute for government control of the economy, which reduces the risks of tyranny and authoritarianism.In his book ''The Road to Serfdom'' (1944), Friedrich Hayek (1899–1992) asserted that the free-market understanding of economic freedom as present in capitalism is a requisite of political freedom.", "He argued that the market mechanism is the only way of deciding what to produce and how to distribute the items without using coercion.", "Milton Friedman and Ronald Reagan also promoted this view.", "Friedman claimed that centralized economic operations are always accompanied by political repression.", "In his view, transactions in a market economy are voluntary and that the wide diversity that voluntary activity permits is a fundamental threat to repressive political leaders and greatly diminishes their power to coerce.", "Some of Friedman's views were shared by John Maynard Keynes, who believed that capitalism was vital for freedom to survive and thrive.", "Freedom House, an American think-tank that conducts international research on, and advocates for, democracy, political freedom and human rights, has argued that \"there is a high and statistically significant correlation between the level of political freedom as measured by Freedom House and economic freedom as measured by the Wall Street Journal/Heritage Foundation survey\".In ''Capital in the Twenty-First Century'' (2013), Thomas Piketty of the Paris School of Economics asserted that inequality is the inevitable consequence of economic growth in a capitalist economy and the resulting concentration of wealth can destabilize democratic societies and undermine the ideals of social justice upon which they are built.States with capitalistic economic systems have thrived under political regimes deemed to be authoritarian or oppressive.", "Singapore has a successful open market economy as a result of its competitive, business-friendly climate and robust rule of law.", "Nonetheless, it often comes under fire for its style of government which, though democratic and consistently one of the least corrupt, operates largely under a one-party rule.", "Furthermore, it does not vigorously defend freedom of expression as evidenced by its government-regulated press, and its penchant for upholding laws protecting ethnic and religious harmony, judicial dignity and personal reputation.", "The private (capitalist) sector in the People's Republic of China has grown exponentially and thrived since its inception, despite having an authoritarian government.", "Augusto Pinochet's rule in Chile led to economic growth and high levels of inequality by using authoritarian means to create a safe environment for investment and capitalism.", "Similarly, Suharto's authoritarian reign and extirpation of the Communist Party of Indonesia allowed for the expansion of capitalism in Indonesia.The term \"capitalism\" in its modern sense is often attributed to Karl Marx.", "In his ''Das Kapital'', Marx analyzed the \"capitalist mode of production\" using a method of understanding today known as Marxism.", "However, Marx himself rarely used the term \"capitalism\" while it was used twice in the more political interpretations of his work, primarily authored by his collaborator Friedrich Engels.", "In the 20th century, defenders of the capitalist system often replaced the term \"capitalism\" with phrases such as free enterprise and private enterprise and replaced \"capitalist\" with rentier and investor in reaction to the negative connotations associated with capitalism." ], [ "Characteristics", "In general, capitalism as an economic system and mode of production can be summarized by the following:* Capital accumulation: production for profit and accumulation as the implicit purpose of all or most of production, constriction or elimination of production formerly carried out on a common social or private household basis.", "* Commodity production: production for exchange on a market; to maximize exchange-value instead of use-value.", "* Private ownership of the means of production:* Primacy of wage labor.", "* The investment of money to make a profit.", "* The use of the price mechanism to allocate resources between competing uses.", "* Economically efficient use of the factors of production and raw materials due to maximization of value added in the production process.", "* Freedom of capitalists to act in their self-interest in managing their business and investments.", "* Capital suppliance by \"the single owner of a firm, or by shareholders in the case of a joint-stock company.", "\"=== Market ===In free market and ''laissez-faire'' forms of capitalism, markets are used most extensively with minimal or no regulation over the pricing mechanism.", "In mixed economies, which are almost universal today, markets continue to play a dominant role, but they are regulated to some extent by the state in order to correct market failures, promote social welfare, conserve natural resources, fund defense and public safety or other rationale.", "In state capitalist systems, markets are relied upon the least, with the state relying heavily on state-owned enterprises or indirect economic planning to accumulate capital.Competition arises when more than one producer is trying to sell the same or similar products to the same buyers.", "Adherents of the capitalist theory believe that competition leads to innovation and more affordable prices.", "Monopolies or cartels can develop, especially if there is no competition.", "A monopoly occurs when a firm has exclusivity over a market.", "Hence, the firm can engage in rent seeking behaviors such as limiting output and raising prices because it has no fear of competition.Governments have implemented legislation for the purpose of preventing the creation of monopolies and cartels.", "In 1890, the Sherman Antitrust Act became the first legislation passed by the United States Congress to limit monopolies.=== Wage labor ===Wage labor, usually referred to as paid work, paid employment, or paid labor, refers to the socioeconomic relationship between a worker and an employer in which the worker sells their labor power under a formal or informal employment contract.", "These transactions usually occur in a labor market where wages or salaries are market-determined.In exchange for the money paid as wages (usual for short-term work-contracts) or salaries (in permanent employment contracts), the work product generally becomes the undifferentiated property of the employer.", "A wage laborer is a person whose primary means of income is from the selling of their labor in this way.=== Profit motive ===The profit motive, in the theory of capitalism, is the desire to earn income in the form of profit.", "Stated differently, the reason for a business's existence is to turn a profit.", "The profit motive functions according to rational choice theory, or the theory that individuals tend to pursue what is in their own best interests.", "Accordingly, businesses seek to benefit themselves and/or their shareholders by maximizing profit.In capitalist theoretics, the profit motive is said to ensure that resources are being allocated efficiently.", "For instance, Austrian economist Henry Hazlitt explains: \"If there is no profit in making an article, it is a sign that the labor and capital devoted to its production are misdirected: the value of the resources that must be used up in making the article is greater than the value of the article itself\".Socialist theorists note that, unlike merchantilists, capitalists accumulate their profits while expecting their profit rates to remain the same.", "This causes problems as earnings in the rest of society do not increase in the same proportion.", "=== Private property ===The relationship between the state, its formal mechanisms, and capitalist societies has been debated in many fields of social and political theory, with active discussion since the 19th century.", "Hernando de Soto is a contemporary Peruvian economist who has argued that an important characteristic of capitalism is the functioning state protection of property rights in a formal property system where ownership and transactions are clearly recorded.According to de Soto, this is the process by which physical assets are transformed into capital, which in turn may be used in many more ways and much more efficiently in the market economy.", "A number of Marxian economists have argued that the Enclosure Acts in England and similar legislation elsewhere were an integral part of capitalist primitive accumulation and that specific legal frameworks of private land ownership have been integral to the development of capitalism.Private property rights are not absolute, as in many countries the state has the power to seize private property, typically for public use, under the powers of eminent domain.=== Market competition ===In capitalist economics, market competition is the rivalry among sellers trying to achieve such goals as increasing profits, market share and sales volume by varying the elements of the marketing mix: price, product, distribution and promotion.", "Merriam-Webster defines competition in business as \"the effort of two or more parties acting independently to secure the business of a third party by offering the most favourable terms\".", "It was described by Adam Smith in ''The Wealth of Nations'' (1776) and later economists as allocating productive resources to their most highly valued uses and encouraging efficiency.", "Smith and other classical economists before Antoine Augustine Cournot were referring to price and non-price rivalry among producers to sell their goods on best terms by bidding of buyers, not necessarily to a large number of sellers nor to a market in final equilibrium.", "Competition is widespread throughout the market process.", "It is a condition where \"buyers tend to compete with other buyers, and sellers tend to compete with other sellers\".", "In offering goods for exchange, buyers competitively bid to purchase specific quantities of specific goods which are available, or might be available if sellers were to choose to offer such goods.", "Similarly, sellers bid against other sellers in offering goods on the market, competing for the attention and exchange resources of buyers.", "Competition results from scarcity, as it is not possible to satisfy all conceivable human wants, and occurs as people try to meet the criteria being used to determine allocation.In the works of Adam Smith, the idea of capitalism is made possible through competition which creates growth.", "Although capitalism has not entered mainstream economics at the time of Smith, it is vital to the construction of his ideal society.", "One of the foundational blocks of capitalism is competition.", "Smith believed that a prosperous society is one where \"everyone should be free to enter and leave the market and change trades as often as he pleases.\"", "He believed that the freedom to act in one's self-interest is essential for the success of a capitalist society.", "The fear arises that if all participants focus on their own goals, society's well-being will be water under the bridge.", "Smith maintains that despite the concerns of intellectuals, \"global trends will hardly be altered if they refrain from pursuing their personal ends.\"", "He insisted that the actions of a few participants cannot alter the course of society.", "Instead, Smith maintained that they should focus on personal progress instead and that this will result in overall growth to the whole.Competition between participants, \"who are all endeavoring to justle one another out of employment, obliges every man to endeavor to execute his work\" through competition towards growth.=== Economic growth ===Economic growth is a characteristic tendency of capitalist economies.", "However, capitalist economies may experience fluctuations in growth that cannot be accounted for by demographic or technological changes.", "These fluctuations, which involve sustained periods of economic growth and recession, are referred to as business cycles in macroeconomics.", "Economic growth is measured as growth in investment, economic output, and economic consumption per capita.", "Changes in hours of employment on their own are not considered as a factor of economic growth.=== As a mode of production ===The capitalist mode of production refers to the systems of organising production and distribution within capitalist societies.", "Private money-making in various forms (renting, banking, merchant trade, production for profit and so on) preceded the development of the capitalist mode of production as such.The term capitalist mode of production is defined by private ownership of the means of production, extraction of surplus value by the owning class for the purpose of capital accumulation, wage-based labor and, at least as far as commodities are concerned, being market-based.Capitalism in the form of money-making activity has existed in the shape of merchants and money-lenders who acted as intermediaries between consumers and producers engaging in simple commodity production (hence the reference to \"merchant capitalism\") since the beginnings of civilisation.", "What is specific about the \"capitalist mode of production\" is that most of the inputs and outputs of production are supplied through the market (i.e.", "they are commodities) and essentially all production is in this mode.", "By contrast, in flourishing feudalism most or all of the factors of production, including labor, are owned by the feudal ruling class outright and the products may also be consumed without a market of any kind, it is production for use within the feudal social unit and for limited trade.", "This has the important consequence that, under capitalism, the whole organisation of the production process is reshaped and re-organised to conform with economic rationality as bounded by capitalism, which is expressed in price relationships between inputs and outputs (wages, non-labor factor costs, sales and profits) rather than the larger rational context faced by society overall—that is, the whole process is organised and re-shaped in order to conform to \"commercial logic\".", "Essentially, capital accumulation comes to define economic rationality in capitalist production.A society, region or nation is capitalist if the predominant source of incomes and products being distributed is capitalist activity, but even so this does not yet mean necessarily that the capitalist mode of production is dominant in that society.Mixed economies rely on the nation they are in to provide some goods or services, while the free market produces and maintains the rest.=== Role of government ===Government agencies regulate the standards of service in many industries, such as airlines and broadcasting, as well as financing a wide range of programs.", "In addition, the government regulates the flow of capital and uses financial tools such as the interest rate to control such factors as inflation and unemployment." ], [ "Supply and demand", "The economic model of supply and demand states that the price P of a product is determined by a balance between production at each price (supply S) and the desires of those with purchasing power at each price (demand D): the diagram shows a positive shift in demand from D1 to D2, resulting in an increase in price (P) and quantity sold (Q) of the product.In capitalist economic structures, supply and demand is an economic model of price determination in a market.", "It postulates that in a perfectly competitive market, the unit price for a particular good will vary until it settles at a point where the quantity demanded by consumers (at the current price) will equal the quantity supplied by producers (at the current price), resulting in an economic equilibrium for price and quantity.The \"basic laws\" of supply and demand, as described by David Besanko and Ronald Braeutigam, are the following four:# If demand increases (demand curve shifts to the right) and supply remains unchanged, then a shortage occurs, leading to a higher equilibrium price.# If demand decreases (demand curve shifts to the left) and supply remains unchanged, then a surplus occurs, leading to a lower equilibrium price.# If demand remains unchanged and supply increases (supply curve shifts to the right), then a surplus occurs, leading to a lower equilibrium price.# If demand remains unchanged and supply decreases (supply curve shifts to the left), then a shortage occurs, leading to a higher equilibrium price.=== Supply schedule ===A supply schedule is a table that shows the relationship between the price of a good and the quantity supplied.=== Demand schedule ===A demand schedule, depicted graphically as the demand curve, represents the amount of some goods that buyers are willing and able to purchase at various prices, assuming all determinants of demand other than the price of the good in question, such as income, tastes and preferences, the price of substitute goods and the price of complementary goods, remain the same.", "According to the law of demand, the demand curve is almost always represented as downward sloping, meaning that as price decreases, consumers will buy more of the good.Just like the supply curves reflect marginal cost curves, demand curves are determined by marginal utility curves.=== Equilibrium ===In the context of supply and demand, economic equilibrium refers to a state where economic forces such as supply and demand are balanced and in the absence of external influences the (equilibrium) values of economic variables will not change.", "For example, in the standard text-book model of perfect competition equilibrium occurs at the point at which quantity demanded and quantity supplied are equal.", "Market equilibrium, in this case, refers to a condition where a market price is established through competition such that the amount of goods or services sought by buyers is equal to the amount of goods or services produced by sellers.", "This price is often called the competitive price or market clearing price and will tend not to change unless demand or supply changes.=== Partial equilibrium ===Partial equilibrium, as the name suggests, takes into consideration only a part of the market to attain equilibrium.", "Jain proposes (attributed to George Stigler): \"A partial equilibrium is one which is based on only a restricted range of data, a standard example is price of a single product, the prices of all other products being held fixed during the analysis\".=== History ===According to Hamid S. Hosseini, the \"power of supply and demand\" was discussed to some extent by several early Muslim scholars, such as fourteenth century Mamluk scholar Ibn Taymiyyah, who wrote: \"If desire for goods increases while its availability decreases, its price rises.", "On the other hand, if availability of the good increases and the desire for it decreases, the price comes down\".Adam SmithJohn Locke's 1691 work ''Some Considerations on the Consequences of the Lowering of Interest and the Raising of the Value of Money'' includes an early and clear description of supply and demand and their relationship.", "In this description, demand is rent: \"The price of any commodity rises or falls by the proportion of the number of buyer and sellers\" and \"that which regulates the price... of goods is nothing else but their quantity in proportion to their rent\".David Ricardo titled one chapter of his 1817 work ''Principles of Political Economy and Taxation'' \"On the Influence of Demand and Supply on Price\".In ''Principles of Political Economy and Taxation'', Ricardo more rigorously laid down the idea of the assumptions that were used to build his ideas of supply and demand.In his 1870 essay \"On the Graphical Representation of Supply and Demand\", Fleeming Jenkin in the course of \"introducing the diagrammatic method into the English economic literature\" published the first drawing of supply and demand curves therein, including comparative statics from a shift of supply or demand and application to the labor market.", "The model was further developed and popularized by Alfred Marshall in the 1890 textbook ''Principles of Economics''." ], [ "Types", "There are many variants of capitalism in existence that differ according to country and region.", "They vary in their institutional makeup and by their economic policies.", "The common features among all the different forms of capitalism are that they are predominantly based on the private ownership of the means of production and the production of goods and services for profit; the market-based allocation of resources; and the accumulation of capital.They include advanced capitalism, corporate capitalism, finance capitalism, free-market capitalism, mercantilism, social capitalism, state capitalism and welfare capitalism.", "Other theoretical variants of capitalism include anarcho-capitalism, community capitalism, humanistic capitalism, neo-capitalism, state monopoly capitalism, and technocapitalism.=== Advanced ===Advanced capitalism is the situation that pertains to a society in which the capitalist model has been integrated and developed deeply and extensively for a prolonged period.", "Various writers identify Antonio Gramsci as an influential early theorist of advanced capitalism, even if he did not use the term himself.", "In his writings, Gramsci sought to explain how capitalism had adapted to avoid the revolutionary overthrow that had seemed inevitable in the 19th century.", "At the heart of his explanation was the decline of raw coercion as a tool of class power, replaced by use of civil society institutions to manipulate public ideology in the capitalists' favour.Jürgen Habermas has been a major contributor to the analysis of advanced-capitalistic societies.", "Habermas observed four general features that characterise advanced capitalism:# Concentration of industrial activity in a few large firms.# Constant reliance on the state to stabilise the economic system.# A formally democratic government that legitimises the activities of the state and dissipates opposition to the system.# The use of nominal wage increases to pacify the most restless segments of the work force.=== Corporate ===Corporate capitalism is a free or mixed-market capitalist economy characterized by the dominance of hierarchical, bureaucratic corporations.=== Finance ===Finance capitalism is the subordination of processes of production to the accumulation of money profits in a financial system.", "In their critique of capitalism, Marxism and Leninism both emphasise the role of finance capital as the determining and ruling-class interest in capitalist society, particularly in the latter stages.Rudolf Hilferding is credited with first bringing the term finance capitalism into prominence through ''Finance Capital'', his 1910 study of the links between German trusts, banks and monopolies—a study subsumed by Vladimir Lenin into ''Imperialism, the Highest Stage of Capitalism'' (1917), his analysis of the imperialist relations of the great world powers.", "Lenin concluded that the banks at that time operated as \"the chief nerve centres of the whole capitalist system of national economy\".", "For the Comintern (founded in 1919), the phrase \"dictatorship of finance capitalism\" became a regular one.Fernand Braudel would later point to two earlier periods when finance capitalism had emerged in human history—with the Genoese in the 16th century and with the Dutch in the 17th and 18th centuries—although at those points it developed from commercial capitalism.", "Giovanni Arrighi extended Braudel's analysis to suggest that a predominance of finance capitalism is a recurring, long-term phenomenon, whenever a previous phase of commercial/industrial capitalist expansion reaches a plateau.=== Free market ===A capitalist free-market economy is an economic system where prices for goods and services are set entirely by the forces of supply and demand and are expected, by its adherents, to reach their point of equilibrium without intervention by government policy.", "It typically entails support for highly competitive markets and private ownership of the means of production.", "''Laissez-faire'' capitalism is a more extensive form of this free-market economy, but one in which the role of the state is limited to protecting property rights.", "In anarcho-capitalist theory, property rights are protected by private firms and market-generated law.", "According to anarcho-capitalists, this entails property rights without statutory law through market-generated tort, contract and property law, and self-sustaining private industry.Fernand Braudel argued that free market exchange and capitalism are to some degree opposed; free market exchange involves transparent public transactions and a large number of equal competitors, while capitalism involves a small number of participants using their capital to control the market via private transactions, control of information, and limitation of competition.=== Mercantile ===The subscription room at Lloyd's of London in the early 19th centuryMercantilism is a nationalist form of early capitalism that came into existence approximately in the late 16th century.", "It is characterized by the intertwining of national business interests with state-interest and imperialism.", "Consequently, the state apparatus is used to advance national business interests abroad.", "An example of this is colonists living in America who were only allowed to trade with and purchase goods from their respective mother countries (e.g., Britain, France and Portugal).", "Mercantilism was driven by the belief that the wealth of a nation is increased through a positive balance of trade with other nations—it corresponds to the phase of capitalist development sometimes called the primitive accumulation of capital.=== Social ===A social market economy is a free-market or mixed-market capitalist system, sometimes classified as a coordinated market economy, where government intervention in price formation is kept to a minimum, but the state provides significant services in areas such as social security, health care, unemployment benefits and the recognition of labor rights through national collective bargaining arrangements.This model is prominent in Western and Northern European countries as well as Japan, albeit in slightly different configurations.", "The vast majority of enterprises are privately owned in this economic model.Rhine capitalism is the contemporary model of capitalism and adaptation of the social market model that exists in continental Western Europe today.=== State ===State capitalism is a capitalist market economy dominated by state-owned enterprises, where the state enterprises are organized as commercial, profit-seeking businesses.", "The designation has been used broadly throughout the 20th century to designate a number of different economic forms, ranging from state-ownership in market economies to the command economies of the former Eastern Bloc.", "According to Aldo Musacchio, a professor at Harvard Business School, state capitalism is a system in which governments, whether democratic or autocratic, exercise a widespread influence on the economy either through direct ownership or various subsidies.", "Musacchio notes a number of differences between today's state capitalism and its predecessors.", "In his opinion, gone are the days when governments appointed bureaucrats to run companies: the world's largest state-owned enterprises are now traded on the public markets and kept in good health by large institutional investors.", "Contemporary state capitalism is associated with the East Asian model of capitalism, dirigisme and the economy of Norway.", "Alternatively, Merriam-Webster defines state capitalism as \"an economic system in which private capitalism is modified by a varying degree of government ownership and control\".In ''Socialism: Utopian and Scientific'', Friedrich Engels argued that state-owned enterprises would characterize the final stage of capitalism, consisting of ownership and management of large-scale production and communication by the bourgeois state.", "In his writings, Vladimir Lenin characterized the economy of Soviet Russia as state capitalist, believing state capitalism to be an early step toward the development of socialism.Some economists and left-wing academics including Richard D. Wolff and Noam Chomsky, as well as many Marxist philosophers and revolutionaries such as Raya Dunayevskaya and C.L.R.", "James, argue that the economies of the former Soviet Union and Eastern Bloc represented a form of state capitalism because their internal organization within enterprises and the system of wage labor remained intact.The term is not used by Austrian School economists to describe state ownership of the means of production.", "The economist Ludwig von Mises argued that the designation of state capitalism was a new label for the old labels of state socialism and planned economy and differed only in non-essentials from these earlier designations.=== Welfare ===Welfare capitalism is capitalism that includes social welfare policies.", "Today, welfare capitalism is most often associated with the models of capitalism found in Central Mainland and Northern Europe such as the Nordic model, social market economy and Rhine capitalism.", "In some cases, welfare capitalism exists within a mixed economy, but welfare states can and do exist independently of policies common to mixed economies such as state interventionism and extensive regulation.A mixed economy is a largely market-based capitalist economy consisting of both private and public ownership of the means of production and economic interventionism through macroeconomic policies intended to correct market failures, reduce unemployment and keep inflation low.", "The degree of intervention in markets varies among different countries.", "Some mixed economies such as France under dirigisme also featured a degree of indirect economic planning over a largely capitalist-based economy.Most modern capitalist economies are defined as mixed economies to some degree, however French economist Thomas Piketty state that capitalist economies might shift to a much more ''laissez-faire'' approach in the near future.=== Eco-capitalism ===Eco-capitalism, also known as \"environmental capitalism\" or (sometimes) \"green capitalism\", is the view that capital exists in nature as \"natural capital\" (ecosystems that have ecological yield) on which all wealth depends.", "Therefore, governments should use market-based policy-instruments (such as a carbon tax) to resolve environmental problems.The term \"Blue Greens\" is often applied to those who espouse eco-capitalism.", "Eco-capitalism can be thought of as the right-wing equivalent to Red Greens.=== Sustainable capitalism ===Sustainable capitalism is a conceptual form of capitalism based upon sustainable practices that seek to preserve humanity and the planet, while reducing externalities and bearing a resemblance of capitalist economic policy.", "A capitalistic economy must expand to survive and find new markets to support this expansion.", "Capitalist systems are often destructive to the environment as well as certain individuals without access to proper representation.", "However, sustainability provides quite the opposite; it implies not only a continuation, but a replenishing of resources.", "Sustainability is often thought of to be related to environmentalism, and sustainable capitalism applies sustainable principles to economic governance and social aspects of capitalism as well.The importance of sustainable capitalism has been more recently recognized, but the concept is not new.", "Changes to the current economic model would have heavy social environmental and economic implications and require the efforts of individuals, as well as compliance of local, state and federal governments.", "Controversy surrounds the concept as it requires an increase in sustainable practices and a marked decrease in current consumptive behaviors.This is a concept of capitalism described in Al Gore and David Blood's manifesto for the Generation Investment Management to describe a long-term political, economic and social structure which would mitigate current threats to the planet and society.", "According to their manifesto, sustainable capitalism would integrate the environmental, social and governance (ESG) aspects into risk assessment in attempt to limit externalities.", "Most of the ideas they list are related to economic changes, and social aspects, but strikingly few are explicitly related to any environmental policy change." ], [ "Capital accumulation", "The accumulation of capital is the process of \"making money\" or growing an initial sum of money through investment in production.", "Capitalism is based on the accumulation of capital, whereby financial capital is invested in order to make a profit and then reinvested into further production in a continuous process of accumulation.", "In Marxian economic theory, this dynamic is called the law of value.", "Capital accumulation forms the basis of capitalism, where economic activity is structured around the accumulation of capital, defined as investment in order to realize a financial profit.", "In this context, \"capital\" is defined as money or a financial asset invested for the purpose of making more money (whether in the form of profit, rent, interest, royalties, capital gain or some other kind of return).In mainstream economics, accounting and Marxian economics, capital accumulation is often equated with investment of profit income or savings, especially in real capital goods.", "The concentration and centralisation of capital are two of the results of such accumulation.", "In modern macroeconomics and econometrics, the phrase \"capital formation\" is often used in preference to \"accumulation\", though the United Nations Conference on Trade and Development (UNCTAD) refers nowadays to \"accumulation\".", "The term \"accumulation\" is occasionally used in national accounts." ], [ "Wage labor", "An industrial worker among heavy steel machine parts (Kinex Bearings, Bytča, Slovakia, –2000)Wage labor refers to the sale of labor under a formal or informal employment contract to an employer.", "These transactions usually occur in a labor market where wages are market determined., defines wage labour succinctly as \"the labour of the worker who sells his own labour-power.\"", "In Marxist economics, these owners of the means of production and suppliers of capital are generally called capitalists.", "The description of the role of the capitalist has shifted, first referring to a useless intermediary between producers, then to an employer of producers, and finally to the owners of the means of production.", "Labor includes all physical and mental human resources, including entrepreneurial capacity and management skills, which are required to produce products and services.", "Production is the act of making goods or services by applying labor power." ], [ "Criticism", "The Industrial Workers of the World poster \"Pyramid of Capitalist System\" (1911)Criticism of capitalism comes from various political and philosophical approaches, including anarchist, socialist, religious and nationalist viewpoints.", "Of those who oppose it or want to modify it, some believe that capitalism should be removed through revolution while others believe that it should be changed slowly through political reforms.Prominent critiques of capitalism allege that it is inherently exploitative, alienating, unstable, unsustainable, and economically inefficient—and that it creates massive economic inequality, commodifies people, degrades the environment, is anti-democratic, and leads to an erosion of human rights because of its incentivization of imperialist expansion and war.Other critics argue that such inequities are not due to the ethic-neutral construct of the economic system commonly known as capitalism, but to the ethics of those who shape and execute the system.", "For example, some contend that Milton Friedman's (human) ethic of 'maximizing shareholder value' creates a harmful form of capitalism, while a Millard Fuller or John Bogle (human) ethic of 'enough' creates a sustainable form.", "Equitable ethics and unified ethical decision-making is theorized to create a less damaging form of capitalism." ], [ "See also", "* Anti-capitalism* Advanced capitalism* Ancient economic thought* Bailout Capitalism* Capitalism (disambiguation)* Christian views on poverty and wealth* Communism* Corporatocracy* Crony capitalism* Economic sociology* Free market* Global financial crisis in September 2008* Humanistic economics* Invisible hand* Late capitalism* ''Le Livre noir du capitalisme''* Market socialism* Perspectives on capitalism by school of thought* Post-capitalism* Post-Fordism* Racial capitalism* Rent-seeking* State monopoly capitalism* Surveillance capitalism* Perestroika" ], [ "References", "; Notes; Bibliography* * * * * * * * * * * * * Krahn, Harvey J., and Graham S. Lowe (1993).", "''Work, Industry, and Canadian Society''.", "2nd ed.", "Scarborough, Ont.", ": Nelson Canada.", "xii, 430 p. * * * * * * * * * * * * *" ], [ "Further reading", "* Alperovitz, Gar (2011).", "''America Beyond Capitalism: Reclaiming Our Wealth, Our Liberty, and Our Democracy, 2nd Edition.''", "Democracy Collaborative Press.", ".", "* * Ascher, Ivan.", "''Portfolio Society: On the Capitalist Mode of Prediction.''", "Zone Books, 2016.", "* Baptist, Edward E. ''The Half Has Never Been Told: Slavery and the Making of American Capitalism.''", "New York, Basic Books, 2014..* * * * Braudel, Fernand.", "''Civilization and Capitalism, 15th-18th Century'', 3 volumes.", "* Callinicos, Alex.", "\"Wage Labour and State Capitalism – A reply to Peter Binns and Mike Haynes\", ''International Socialism'', 2nd series, 12, Spring 1979.", "* * Farl, Erich.", "\"The Genealogy of State Capitalism\".", "In: ''International'' London, vol.", "2, no.", "1, 1973.", "* * Gough, Ian. ''", "State Expenditure in Advanced Capitalism '' New Left Review.", "* Habermas, J.", "1973 ''Legitimation Crisis'' (eng.", "translation by T. McCarthy).", "Boston, Beacon.", "From Google books ; excerpt.", "* * Hyman, Louis and Edward E. Baptist (2014).", "''American Capitalism: A Reader.''", "Simon & Schuster.", ".", "* * * * Jameson, Fredric (1991).", "''Postmodernism, or, the Cultural Logic of Late Capitalism''.", "* Kotler, Philip (2015).", "''Confronting Capitalism: Real Solutions for a Troubled Economic System.''", "AMACOM.", "* Mandel, Ernest (1999).", "''Late Capitalism.''", "* * Marcel van der Linden, ''Western Marxism and the Soviet Union''.", "New York, Brill Publishers, 2007.", "* Mayfield, Anthony.", "\"Economics\", in his ''On the Brink: Resource Depletion, Debt Collapse, and Super-technology'' (Vancouver, B.C., Canada: On the Brink Publishing, 2013), pp. 50–104.", "* * * * Panitch, Leo, and Sam Gindin (2012).", "''The Making of Global Capitalism: the Political Economy of American Empire''.", "London, Verso.", ".", "* * * Polanyi, Karl (2001).", "''The Great Transformation: The Political and Economic Origins of Our Time.''", "Beacon Press; 2nd ed.", "* * Richards, Jay W. (2009).", "''Money, Greed, and God: Why Capitalism is the Solution and Not the Problem''.", "New York: HarperOne.", "* Roberts, Paul Craig (2013).", "''The Failure of Laissez-faire Capitalism: towards a New Economics for a Full World''.", "Atlanta, Ga.: Clarity Press.", "* Robinson, William I.", "''Global Capitalism and the Crisis of Humanity.''", "Cambridge University Press, 2014.", "* * Hoevet, Ocean.", "\"Capital as a Social Relation\" (New Palgrave article)* Sombart, Werner (1916) ''Der moderne Kapitalismus.", "Historisch-systematische Darstellung des gesamteuropäischen Wirtschaftslebens von seinen Anfängen bis zur Gegenwart.''", "Final edn.", "1916, repr.", "1969, paperback edn.", "(3 vols.", "in 6): 1987 Munich: dtv.", "(Also in Spanish; no English translation yet.", ")* Tarnoff, Ben, \"Better, Faster, Stronger\" (review of John Tinnell, ''The Philosopher of Palo Alto: Mark Weisner, Xerox PARC, and the Original Internet of Things'', University of Chicago Press, 347 pp.", "; and Malcolm Harris, ''Palo Alto: A History of California, Capitalism, and the World'', Little, Brown, 708 pp.", "), ''The New York Review of Books'', vol.", "LXX, no.", "14 (21 September 2023), pp. 38–40.", "\"Palo Alto is a place where the United States' contradictions are sharpened to their finest points, above all the defining and enduring contradictions between democratic principle and antidemocratic practice.", "There is nothing as American as celebrating equality while subverting it.", "Or as Californian.\"", "(p. 40.", ")* * *" ], [ "External links", "* * Capitalism at ''Encyclopædia Britannica'' Online.", "* Selected Titles on Capitalism and Its Discontents .", "Harvard University Press." ] ]

[ [ "Cross ownership" ], [ "Introduction", "'''Cross ownership''' is a method of reinforcing business relationships by owning stock in the companies with which a given company does business.", "Heavy cross ownership is referred to as circular ownership.In the US, \"cross ownership\" also refers to a type of investment in different mass-media properties in one market." ], [ "Cross ownership of stock", "Countries noted to have high levels of cross ownership include:* Japan* GermanyPositives of cross ownership:* Closely ties each business to the economic destiny of its business partners* Promotes a slow rate of economic changeCross ownership of shares is criticized for:* Stagnating the economy* Wasting capital that could be used to improve productivity* Expanding economic downturns by preventing reallocation of capital* Lessening control of shareholders over corporate leadership.A major factor in perpetuating cross ownership of shares is a high capital gains tax rate.", "A company has less incentive to sell cross owned shares if taxes are high because of the immediate reduction in the value of the assets.For example, a company owns $1000 of stock in another company that was originally purchased for $200.If the capital gains tax rate is 25% (like in Germany), the profit of $800 would be taxed for $200, causing the company to take a $200 loss on the sale.Long term cross ownership of shares combined with a high capital tax rate greatly increases periods of asset deflation both in time and in severity." ], [ "Media cross ownership", "Cross ownership also refers to a type of media ownership in which one type of communications (say a newspaper) owns or is the sister company of another type of medium (such as a radio or TV station).", "One example is ''The New York Times''s former ownership of WQXR Radio and the ''Chicago Tribune'''s similar relationship with WGN Radio (WGN-AM) and Television (WGN-TV).The Federal Communications Commission generally does not allow cross ownership, to keep from one license holder having too much local media ownership, unless the license holder obtains a waiver, such as News Corporation and the Tribune Company have in New York.The mid-1970s cross-ownership guidelines grandfathered already-existing cross ownerships, such as ''Tribune''-WGN, ''New York Times''-WQXR and the ''New York Daily News'' ownership of WPIX Television and Radio." ], [ "References" ] ]

[ [ "Cardiology" ], [ "Introduction", "'''Cardiology''' () is the study of the heart.", "Cardiology is a branch of medicine that deals with disorders of the heart and the cardiovascular system.", "The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease, and electrophysiology.", "Physicians who specialize in this field of medicine are called '''cardiologists''', a specialty of internal medicine.", "Pediatric cardiologists are pediatricians who specialize in cardiology.", "Physicians who specialize in cardiac surgery are called '''cardiothoracic surgeons''' or '''cardiac surgeons''', a specialty of general surgery." ], [ "Specializations", "All cardiologists in the branch of medicine study the disorders of the heart, but the study of adult and child heart disorders each require different training pathways.", "Therefore, an adult cardiologist (often simply called \"cardiologist\") is inadequately trained to take care of children, and pediatric cardiologists are not trained to treat adult heart disease.", "Surgical aspects outside of cardiac rhythm device implant are not included in cardiology and are in the domain of cardiothoracic surgery.", "For example, coronary artery bypass surgery (CABG), cardiopulmonary bypass and valve replacement are surgical procedures performed by surgeons, not cardiologists.", "However, some invasive procedures such as cardiac catheterization and pacemaker implantation are performed by cardiologists.===Adult cardiology===Cardiology is a specialty of internal medicine.To become a cardiologist in the United States, a three-year residency in internal medicine is followed by a three-year fellowship in cardiology.", "It is possible to specialize further in a sub-specialty.", "Recognized sub-specialties in the U.S. by the Accreditation Council for Graduate Medical Education are cardiac electrophysiology, echocardiography, interventional cardiology, and nuclear cardiology.", "Recognized subspecialties in the U.S. by the American Osteopathic Association Bureau of Osteopathic Specialists include clinical cardiac electrophysiology and interventional cardiology.In India, a three-year residency in General Medicine or Pediatrics after M.B.B.S.", "and then three years of residency in cardiology are needed to be a D.M.", "(holder of a Doctorate of Medicine D.M.", ")/Diplomate of National Board (DNB) in Cardiology.Per Doximity, adult cardiologists earn an average of $436,849 per year in the U.S.==== Cardiac electrophysiology ====Cardiac electrophysiology is the science of elucidating, diagnosing, and treating the electrical activities of the heart.", "The term is usually used to describe studies of such phenomena by invasive (intracardiac) catheter recording of spontaneous activity as well as of cardiac responses to programmed electrical stimulation (PES).", "These studies are performed to assess complex arrhythmias, elucidate symptoms, evaluate abnormal electrocardiograms, assess risk of developing arrhythmias in the future, and design treatment.", "These procedures increasingly include therapeutic methods (typically radiofrequency ablation, or cryoablation) in addition to diagnostic and prognostic procedures.Other therapeutic modalities employed in this field include antiarrhythmic drug therapy and implantation of pacemakers and automatic implantable cardioverter-defibrillators (AICD).The cardiac electrophysiology study typically measures the response of the injured or cardiomyopathic myocardium to PES on specific pharmacological regimens in order to assess the likelihood that the regimen will successfully prevent potentially fatal sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) in the future.", "Sometimes a ''series'' of electrophysiology-study drug trials must be conducted to enable the cardiologist to select the one regimen for long-term treatment that best prevents or slows the development of VT or VF following PES.", "Such studies may also be conducted in the presence of a newly implanted or newly replaced cardiac pacemaker or AICD.==== Clinical cardiac electrophysiology ====Clinical cardiac electrophysiology is a branch of the medical specialty of cardiology and is concerned with the study and treatment of rhythm disorders of the heart.", "Cardiologists with expertise in this area are usually referred to as electrophysiologists.", "Electrophysiologists are trained in the mechanism, function, and performance of the electrical activities of the heart.", "Electrophysiologists work closely with other cardiologists and cardiac surgeons to assist or guide therapy for heart rhythm disturbances (arrhythmias).", "They are trained to perform interventional and surgical procedures to treat cardiac arrhythmia.The training required to become an electrophysiologist is long and requires eight years after medical school (within the U.S.).", "Three years of internal medicine residency, three years of cardiology fellowship, and two years of clinical cardiac electrophysiology.==== Cardiogeriatrics ====Cardiogeriatrics, or geriatric cardiology, is the branch of cardiology and geriatric medicine that deals with the cardiovascular disorders in elderly people.Cardiac disorders such as coronary heart disease, including myocardial infarction, heart failure, cardiomyopathy, and arrhythmias such as atrial fibrillation, are common and are a major cause of mortality in elderly people.", "Vascular disorders such as atherosclerosis and peripheral arterial disease cause significant morbidity and mortality in aged people.==== Imaging ====Cardiac imaging includes echocardiography (echo), cardiac magnetic resonance imaging (CMR), and computed tomography of the heart.Those who specialize in cardiac imaging may undergo more training in all imaging modes or focus on a single imaging modality.Echocardiography (or \"echo\") uses standard two-dimensional, three-dimensional, and Doppler ultrasound to create images of the heart.Those who specialize in echo may spend a significant amount of their clinical time reading echos and performing transesophageal echo, in particular using the latter during procedures such as insertion of a left atrial appendage occlusion device.Cardiac MRI utilizes special protocols to image heart structure and function with specific sequences for certain diseases such as hemochromatosis and amyloidosis.Cardiac CT utilizes special protocols to image heart structure and function with particular emphasis on coronary arteries.==== Interventional cardiology ====Interventional cardiology is a branch of cardiology that deals specifically with the catheter based treatment of structural heart diseases.", "A large number of procedures can be performed on the heart by catheterization, including angiogram, angioplasty, atherectomy, and stent implantation.", "These procedures all involve insertion of a sheath into the femoral artery or radial artery (but, in practice, any large peripheral artery or vein) and cannulating the heart under visualization (most commonly fluoroscopy).", "This cannulation allows indirect access to the heart, bypassing the trauma caused by surgical opening of the chest.The main advantages of using the interventional cardiology or radiology approach are the avoidance of the scars and pain, and long post-operative recovery.", "Additionally, interventional cardiology procedure of primary angioplasty is now the gold standard of care for an acute myocardial infarction.", "This procedure can also be done proactively, when areas of the vascular system become occluded from atherosclerosis.", "The Cardiologist will thread this sheath through the vascular system to access the heart.", "This sheath has a balloon and a tiny wire mesh tube wrapped around it, and if the cardiologist finds a blockage or stenosis, they can inflate the balloon at the occlusion site in the vascular system to flatten or compress the plaque against the vascular wall.", "Once that is complete a stent is placed as a type of scaffold to hold the vasculature open permanently.====Cardiomyopathy/heart failure====A relatively newer specialization of cardiology is in the field of heart failure and heart transplant.", "Specialization of general cardiology to just that of the cardiomyopathies leads to also specializing in heart transplant and pulmonary hypertension.", "Cardiomyopathy is a heart disease of the heart muscle, where the heart muscle becomes inflamed and thick.", "====Cardiooncology====A recent specialization of cardiology is that of cardiooncology.This area specializes in the cardiac management in those with cancer and in particular those with plans for chemotherapy or those who have experienced cardiac complications of chemotherapy.=== Preventive cardiology and cardiac rehabilitation ===In recent times, the focus is gradually shifting to preventive cardiology due to increased cardiovascular disease burden at an early age.", "According to the WHO, 37% of all premature deaths are due to cardiovascular diseases and out of this, 82% are in low and middle income countries.", "Clinical cardiology is the sub specialty of cardiology which looks after preventive cardiology and cardiac rehabilitation.", "Preventive cardiology also deals with routine preventive checkup though noninvasive tests, specifically electrocardiography, fasegraphy, stress tests, lipid profile and general physical examination to detect any cardiovascular diseases at an early age, while cardiac rehabilitation is the upcoming branch of cardiology which helps a person regain their overall strength and live a normal life after a cardiovascular event.", "A subspecialty of preventive cardiology is sports cardiology.", "Because heart disease is the leading cause of death in the world including United States (cdc.gov), national health campaigns and randomized control research has developed to improve heart health.===Pediatric cardiology===Tetralogy of FallotHelen B. Taussig is known as the founder of pediatric cardiology.", "She became famous through her work with Tetralogy congenital heart defect in which oxygenated and deoxygenated blood enters the circulatory system resulting from a ventricular septal defect (VSD) right beneath the aorta.", "This condition causes newborns to have a bluish-tint, cyanosis, and have a deficiency of oxygen to their tissues, hypoxemia.", "She worked with Alfred Blalock and Vivien Thomas at the Johns Hopkins Hospital where they experimented with dogs to look at how they would attempt to surgically cure these \"blue babies\".", "They eventually figured out how to do just that by the anastomosis of the systemic artery to the pulmonary artery and called this the Blalock-Taussig Shunt.Tetralogy of Fallot, pulmonary atresia, double outlet right ventricle, transposition of the great arteries, persistent truncus arteriosus, and Ebstein's anomaly are various congenital cyanotic heart diseases, in which the blood of the newborn is not oxygenated efficiently, due to the heart defect.===Adult congenital heart disease===As more children with congenital heart disease are surviving into adulthood, a hybrid of adult & pediatric cardiology has emerged called adult congenital heart disease (ACHD).This field can be entered as either adult or pediatric cardiology.ACHD specializes in congenital diseases in the setting of adult diseases (e.g., coronary artery disease, COPD, diabetes) that is, otherwise, atypical for adult or pediatric cardiology." ], [ "The heart", "Blood flow through the valvesAs the center focus of cardiology, the heart has numerous anatomical features (e.g., atria, ventricles, heart valves) and numerous physiological features (e.g., systole, heart sounds, afterload) that have been encyclopedically documented for many centuries.", "The heart is located in the middle of the abdomen with its tip slightly towards the left side of the abdomen.Disorders of the heart lead to heart disease and cardiovascular disease and can lead to a significant number of deaths: cardiovascular disease is the leading cause of death in the U.S. and caused 24.95% of total deaths in 2008.The primary responsibility of the heart is to pump blood throughout the body.It pumps blood from the body — called the systemic circulation — through the lungs — called the pulmonary circulation — and then back out to the body.This means that the heart is connected to and affects the entirety of the body.", "Simplified, the heart is a circuit of the circulation.", "While plenty is known about the healthy heart, the bulk of study in cardiology is in disorders of the heart and restoration, and where possible, of function.The heart is a muscle that squeezes blood and functions like a pump.", "The heart's systems can be classified as either electrical or mechanical, and both of these systems are susceptible to failure or dysfunction.The electrical system of the heart is centered on the periodic contraction (squeezing) of the muscle cells that is caused by the cardiac pacemaker located in the sinoatrial node.The study of the electrical aspects is a sub-field of electrophysiology called cardiac electrophysiology and is epitomized with the electrocardiogram (ECG/EKG).The action potentials generated in the pacemaker propagate throughout the heart in a specific pattern.", "The system that carries this potential is called the electrical conduction system.Dysfunction of the electrical system manifests in many ways and may include Wolff–Parkinson–White syndrome, ventricular fibrillation, and heart block.The mechanical system of the heart is centered on the fluidic movement of blood and the functionality of the heart as a pump.The mechanical part is ultimately the purpose of the heart and many of the disorders of the heart disrupt the ability to move blood.Heart failure is one condition in which the mechanical properties of the heart have failed or are failing, which means insufficient blood is being circulated.", "Failure to move a sufficient amount of blood through the body can cause damage or failure of other organs and may result in death if severe.=== Coronary circulation ===Coronary circulation is the circulation of blood in the blood vessels of the heart muscle (the myocardium).", "The vessels that deliver oxygen-rich blood to the myocardium are known as coronary arteries.", "The vessels that remove the deoxygenated blood from the heart muscle are known as cardiac veins.", "These include the great cardiac vein, the middle cardiac vein, the small cardiac vein and the anterior cardiac veins.As the left and right coronary arteries run on the surface of the heart, they can be called epicardial coronary arteries.", "These arteries, when healthy, are capable of autoregulation to maintain coronary blood flow at levels appropriate to the needs of the heart muscle.", "These relatively narrow vessels are commonly affected by atherosclerosis and can become blocked, causing angina or myocardial infarction (a.k.a a heart attack).", "The coronary arteries that run deep within the myocardium are referred to as subendocardial.The coronary arteries are classified as \"end circulation\", since they represent the only source of blood supply to the myocardium; there is very little redundant blood supply, which is why blockage of these vessels can be so critical.=== Cardiac examination ===The cardiac examination (also called the \"precordial exam\"), is performed as part of a physical examination, or when a patient presents with chest pain suggestive of a cardiovascular pathology.", "It would typically be modified depending on the indication and integrated with other examinations especially the respiratory examination.Like all medical examinations, the cardiac examination follows the standard structure of inspection, palpation and auscultation." ], [ "Heart disorders", "Cardiology is concerned with the normal functionality of the heart and the deviation from a healthy heart.", "Many disorders involve the heart itself, but some are outside of the heart and in the vascular system.", "Collectively, the two are jointly termed the cardiovascular system, and diseases of one part tend to affect the other.=== Coronary artery disease ===Coronary artery disease, also known as \"ischemic heart disease\", is a group of diseases that includes: stable angina, unstable angina, myocardial infarction, and is one of the causes of sudden cardiac death.", "It is within the group of cardiovascular diseases of which it is the most common type.", "A common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck, or jaw.", "Occasionally it may feel like heartburn.", "Usually symptoms occur with exercise or emotional stress, last less than a few minutes, and get better with rest.", "Shortness of breath may also occur and sometimes no symptoms are present.", "The first sign is occasionally a heart attack.", "Other complications include heart failure or an irregular heartbeat.Risk factors include: high blood pressure, smoking, diabetes, lack of exercise, obesity, high blood cholesterol, poor diet, and excessive alcohol, among others.", "Other risks include depression.", "The underlying mechanism involves atherosclerosis of the arteries of the heart.", "A number of tests may help with diagnoses including: electrocardiogram, cardiac stress testing, coronary computed tomographic angiography, and coronary angiogram, among others.Prevention is by eating a healthy diet, regular exercise, maintaining a healthy weight and not smoking.", "Sometimes medication for diabetes, high cholesterol, or high blood pressure are also used.", "There is limited evidence for screening people who are at low risk and do not have symptoms.", "Treatment involves the same measures as prevention.", "Additional medications such as antiplatelets including aspirin, beta blockers, or nitroglycerin may be recommended.", "Procedures such as percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG) may be used in severe disease.", "In those with stable CAD it is unclear if PCI or CABG in addition to the other treatments improve life expectancy or decreases heart attack risk.In 2013 CAD was the most common cause of death globally, resulting in 8.14 million deaths (16.8%) up from 5.74 million deaths (12%) in 1990.The risk of death from CAD for a given age has decreased between 1980 and 2010 especially in developed countries.", "The number of cases of CAD for a given age has also decreased between 1990 and 2010.In the U.S. in 2010 about 20% of those over 65 had CAD, while it was present in 7% of those 45 to 64, and 1.3% of those 18 to 45.Rates are higher among men than women of a given age.===Cardiomyopathy===Heart failure or formally cardiomyopathy, is the impaired function of the heart and there are numerous causes and forms of heart failure.===Cardiac arrhythmia===Cardiac arrhythmia, also known as \"cardiac dysrhythmia\" or \"irregular heartbeat\", is a group of conditions in which the heartbeat is too fast, too slow, or irregular in its rhythm.", "A heart rate that is too fast – above 100 beats per minute in adults – is called tachycardia.", "A heart rate that is too slow – below 60 beats per minute – is called bradycardia.", "Many types of arrhythmia present no symptoms.", "When symptoms are present, they may include palpitations, or feeling a pause between heartbeats.", "More serious symptoms may include lightheadedness, passing out, shortness of breath, or chest pain.", "While most types of arrhythmia are not serious, some predispose a person to complications such as stroke or heart failure.", "Others may result in cardiac arrest.There are four main types of arrhythmia: extra beats, supraventricular tachycardias, ventricular arrhythmias, and bradyarrhythmias.", "Extra beats include premature atrial contractions, premature ventricular contractions, and premature junctional contractions.", "Supraventricular tachycardias include atrial fibrillation, atrial flutter, and paroxysmal supraventricular tachycardia.", "Ventricular arrhythmias include ventricular fibrillation and ventricular tachycardia.", "Arrhythmias are due to problems with the electrical conduction system of the heart.", "Arrhythmias may occur in children; however, the normal range for the heart rate is different and depends on age.", "A number of tests can help diagnose arrhythmia, including an electrocardiogram and Holter monitor.Most arrhythmias can be effectively treated.", "Treatments may include medications, medical procedures such as a pacemaker, and surgery.", "Medications for a fast heart rate may include beta blockers or agents that attempt to restore a normal heart rhythm such as procainamide.", "This later group may have more significant side effects especially if taken for a long period of time.", "Pacemakers are often used for slow heart rates.", "Those with an irregular heartbeat are often treated with blood thinners to reduce the risk of complications.", "Those who have severe symptoms from an arrhythmia may receive urgent treatment with a jolt of electricity in the form of cardioversion or defibrillation.Arrhythmia affects millions of people.", "In Europe and North America, as of 2014, atrial fibrillation affects about 2% to 3% of the population.", "Atrial fibrillation and atrial flutter resulted in 112,000 deaths in 2013, up from 29,000 in 1990.Sudden cardiac death is the cause of about half of deaths due to cardiovascular disease or about 15% of all deaths globally.", "About 80% of sudden cardiac death is the result of ventricular arrhythmias.", "Arrhythmias may occur at any age but are more common among older people.=== Cardiac arrest ===Cardiac arrest is a sudden stop in effective blood flow due to the failure of the heart to contract effectively.", "Symptoms include loss of consciousness and abnormal or absent breathing.", "Some people may have chest pain, shortness of breath, or nausea before this occurs.", "If not treated within minutes, death usually occurs.The most common cause of cardiac arrest is coronary artery disease.", "Less common causes include major blood loss, lack of oxygen, very low potassium, heart failure, and intense physical exercise.", "A number of inherited disorders may also increase the risk including long QT syndrome.", "The initial heart rhythm is most often ventricular fibrillation.", "The diagnosis is confirmed by finding no pulse.", "While a cardiac arrest may be caused by heart attack or heart failure these are not the same.Prevention includes not smoking, physical activity, and maintaining a healthy weight.", "Treatment for cardiac arrest is immediate cardiopulmonary resuscitation (CPR) and, if a shockable rhythm is present, defibrillation.", "Among those who survive targeted temperature management may improve outcomes.", "An implantable cardiac defibrillator may be placed to reduce the chance of death from recurrence.In the United States, cardiac arrest outside of hospital occurs in about 13 per 10,000 people per year (326,000 cases).", "In hospital cardiac arrest occurs in an additional 209,000 Cardiac arrest becomes more common with age.", "It affects males more often than females.", "The percentage of people who survive with treatment is about 8%.", "Many who survive have significant disability.", "Many U.S. television shows, however, have portrayed unrealistically high survival rates of 67%.=== Hypertension ===Hypertension, also known as \"high blood pressure\", is a long term medical condition in which the blood pressure in the arteries is persistently elevated.", "High blood pressure usually does not cause symptoms.", "Long term high blood pressure, however, is a major risk factor for coronary artery disease, stroke, heart failure, peripheral vascular disease, vision loss, and chronic kidney disease.Lifestyle factors can increase the risk of hypertension.", "These include excess salt in the diet, excess body weight, smoking, and alcohol consumption.", "Hypertension can also be caused by other diseases, or occur as a side-effect of drugs.Blood pressure is expressed by two measurements, the systolic and diastolic pressures, which are the maximum and minimum pressures, respectively.", "Normal blood pressure when at rest is within the range of 100–140 millimeters mercury (mmHg) systolic and 60–90 mmHg diastolic.", "High blood pressure is present if the resting blood pressure is persistently at or above 140/90 mmHg for most adults.", "Different numbers apply to children.", "When diagnosing high blood pressure, ambulatory blood pressure monitoring over a 24-hour period appears to be more accurate than \"in-office\" blood pressure measurement at a physician's office or other blood pressure screening location.Lifestyle changes and medications can lower blood pressure and decrease the risk of health complications.", "Lifestyle changes include weight loss, decreased salt intake, physical exercise, and a healthy diet.", "If changes in lifestyle are insufficient, blood pressure medications may be used.", "A regimen of up to three medications effectively controls blood pressure in 90% of people.", "The treatment of moderate to severe high arterial blood pressure (defined as >160/100 mmHg) with medication is associated with an improved life expectancy and reduced morbidity.", "The effect of treatment for blood pressure between 140/90 mmHg and 160/100 mmHg is less clear, with some studies finding benefits while others do not.", "High blood pressure affects between 16% and 37% of the population globally.", "In 2010, hypertension was believed to have been a factor in 18% (9.4 million) deaths.==== Essential vs Secondary hypertension ====Essential hypertension is the form of hypertension that by definition has no identifiable cause.", "It is the most common type of hypertension, affecting 95% of hypertensive patients, it tends to be familial and is likely to be the consequence of an interaction between environmental and genetic factors.", "Prevalence of essential hypertension increases with age, and individuals with relatively high blood pressure at younger ages are at increased risk for the subsequent development of hypertension.Hypertension can increase the risk of cerebral, cardiac, and renal events.Secondary hypertension is a type of hypertension which is caused by an identifiable underlying secondary cause.", "It is much less common than essential hypertension, affecting only 5% of hypertensive patients.", "It has many different causes including endocrine diseases, kidney diseases, and tumors.", "It also can be a side effect of many medications.==== Complications of hypertension ====Main complications of persistent high blood pressureComplications of hypertension are clinical outcomes that result from persistent elevation of blood pressure.", "Hypertension is a risk factor for all clinical manifestations of atherosclerosis since it is a risk factor for atherosclerosis itself.", "It is an independent predisposing factor for heart failure, coronary artery disease, stroke, renal disease, and peripheral arterial disease.", "It is the most important risk factor for cardiovascular morbidity and mortality, in industrialized countries.=== Congenital heart defects ===A congenital heart defect, also known as a \"congenital heart anomaly\" or \"congenital heart disease\", is a problem in the structure of the heart that is present at birth.", "Signs and symptoms depend on the specific type of problem.", "Symptoms can vary from none to life-threatening.", "When present they may include rapid breathing, bluish skin, poor weight gain, and feeling tired.", "It does not cause chest pain.", "Most congenital heart problems do not occur with other diseases.", "Complications that can result from heart defects include heart failure.The cause of a congenital heart defect is often unknown.", "Certain cases may be due to infections during pregnancy such as rubella, use of certain medications or drugs such as alcohol or tobacco, parents being closely related, or poor nutritional status or obesity in the mother.", "Having a parent with a congenital heart defect is also a risk factor.", "A number of genetic conditions are associated with heart defects including Down syndrome, Turner syndrome, and Marfan syndrome.", "Congenital heart defects are divided into two main groups: cyanotic heart defects and non-cyanotic heart defects, depending on whether the child has the potential to turn bluish in color.", "The problems may involve the interior walls of the heart, the heart valves, or the large blood vessels that lead to and from the heart.Congenital heart defects are partly preventable through rubella vaccination, the adding of iodine to salt, and the adding of folic acid to certain food products.", "Some defects do not need treatment.", "Other may be effectively treated with catheter based procedures or heart surgery.", "Occasionally a number of operations may be needed.", "Occasionally heart transplantation is required.", "With appropriate treatment outcomes, even with complex problems, are generally good.Heart defects are the most common birth defect.", "In 2013 they were present in 34.3 million people globally.", "They affect between 4 and 75 per 1,000 live births depending upon how they are diagnosed.", "About 6 to 19 per 1,000 cause a moderate to severe degree of problems.", "Congenital heart defects are the leading cause of birth defect-related deaths.", "In 2013 they resulted in 323,000 deaths down from 366,000 deaths in 1990.==== Tetralogy of Fallot ====Tetralogy of Fallot is the most common congenital heart disease arising in 1–3 cases per 1,000 births.", "The cause of this defect is a ventricular septal defect (VSD) and an overriding aorta.", "These two defects combined causes deoxygenated blood to bypass the lungs and going right back into the circulatory system.", "The modified Blalock-Taussig shunt is usually used to fix the circulation.", "This procedure is done by placing a graft between the subclavian artery and the ipsilateral pulmonary artery to restore the correct blood flow.==== Pulmonary atresia ====Pulmonary atresia happens in 7–8 per 100,000 births and is characterized by the aorta branching out of the right ventricle.", "This causes the deoxygenated blood to bypass the lungs and enter the circulatory system.", "Surgeries can fix this by redirecting the aorta and fixing the right ventricle and pulmonary artery connection.There are two types of pulmonary atresia, classified by whether or not the baby also has a ventricular septal defect.", "* Pulmonary atresia with an intact ventricular septum: This type of pulmonary atresia is associated with complete and intact septum between the ventricles.", "* Pulmonary atresia with a ventricular septal defect: This type of pulmonary atresia happens when a ventricular septal defect allows blood to flow into and out of the right ventricle.==== Double outlet right ventricle ====Double outlet right ventricle (DORV) is when both great arteries, the pulmonary artery and the aorta, are connected to the right ventricle.", "There is usually a VSD in different particular places depending on the variations of DORV, typically 50% are subaortic and 30%.", "The surgeries that can be done to fix this defect can vary due to the different physiology and blood flow in the defected heart.", "One way it can be cured is by a VSD closure and placing conduits to restart the blood flow between the left ventricle and the aorta and between the right ventricle and the pulmonary artery.", "Another way is systemic-to-pulmonary artery shunt in cases associated with pulmonary stenosis.", "Also, a balloon atrial septostomy can be done to relieve hypoxemia caused by DORV with the Taussig-Bing anomaly while surgical correction is awaited.==== Transposition of great arteries ====Dextro-transposition of the Great ArteriesThere are two different types of transposition of the great arteries, Dextro-transposition of the great arteries and Levo-transposition of the great arteries, depending on where the chambers and vessels connect.", "Dextro-transposition happens in about 1 in 4,000 newborns and is when the right ventricle pumps blood into the aorta and deoxygenated blood enters the bloodstream.", "The temporary procedure is to create an atrial septal defect.", "A permanent fix is more complicated and involves redirecting the pulmonary return to the right atrium and the systemic return to the left atrium, which is known as the Senning procedure.", "The Rastelli procedure can also be done by rerouting the left ventricular outflow, dividing the pulmonary trunk, and placing a conduit in between the right ventricle and pulmonary trunk.", "Levo-transposition happens in about 1 in 13,000 newborns and is characterized by the left ventricle pumping blood into the lungs and the right ventricle pumping the blood into the aorta.", "This may not produce problems at the beginning, but will eventually due to the different pressures each ventricle uses to pump blood.", "Switching the left ventricle to be the systemic ventricle and the right ventricle to pump blood into the pulmonary artery can repair levo-transposition.==== Persistent truncus arteriosus ====Persistent truncus arteriosus is when the truncus arteriosus fails to split into the aorta and pulmonary trunk.", "This occurs in about 1 in 11,000 live births and allows both oxygenated and deoxygenated blood into the body.", "The repair consists of a VSD closure and the Rastelli procedure.==== Ebstein anomaly ====Ebstein's anomaly is characterized by a right atrium that is significantly enlarged and a heart that is shaped like a box.", "This is very rare and happens in less than 1% of congenital heart disease cases.", "The surgical repair varies depending on the severity of the disease.Pediatric cardiology is a sub-specialty of pediatrics.", "To become a pediatric cardiologist in the U.S., one must complete a three-year residency in pediatrics, followed by a three-year fellowship in pediatric cardiology.", "Per doximity, pediatric cardiologists make an average of $303,917 in the U.S." ], [ "Diagnostic tests in cardiology", "Diagnostic tests in cardiology are the methods of identifying heart conditions associated with healthy vs. unhealthy, pathologic heart function.", "The starting point is obtaining a medical history, followed by Auscultation.", "Then blood tests, electrophysiological procedures, and cardiac imaging can be ordered for further analysis.", "Electrophysiological procedures include electrocardiogram, cardiac monitoring, cardiac stress testing, and the electrophysiology study." ], [ "Trials", "Cardiology is known for randomized controlled trials that guide clinical treatment of cardiac diseases.", "While dozens are published every year, there are landmark trials that shift treatment significantly.", "Trials often have an acronym of the trial name, and this acronym is used to reference the trial and its results.", "Some of these landmark trials include:* V-HeFT (1986) — use of vasodilators (hydralazine & isosorbide dinitrate) in heart failure* ISIS-2 (1988) — use of aspirin in myocardial infarction* CASE I (1991) — use of antiarrhythmic agents after a heart attack increases mortality* SOLVD (1991) — use of ACE inhibitors in heart failure* 4S (1994) — statins reduce risk of heart disease* CURE (1991) — use of dual antiplatelet therapy in NSTEMI* MIRACLE (2002) — use of cardiac resynchronization therapy in heart failure* SCD-HeFT (2005) — the use of implantable cardioverter-defibrillator in heart failure* RELY (2009), ROCKET-AF (2011), ARISTOTLE (2011) — use of DOACs in atrial fibrillation instead of warfarin* PARADIGM-HF (2014) — use of angiotensin-neprilysin inhibitor in heart failure* ISCHEMIA (2020) — medical therapy is as good as coronary stents in stable heart disease* EMPEROR-Preserved (2021) — SGLT2 receptors in heart failure" ], [ "Cardiology community", "=== Associations ===* American College of Cardiology* American Heart Association* European Society of Cardiology* Heart Rhythm Society* Canadian Cardiovascular Society* Indian Heart Association* National Heart Foundation of Australia* Cardiology Society of India=== Journals ===* Acta Cardiologica* American Journal of Cardiology* Annals of Cardiac Anaesthesia* Current Research: Cardiology* Cardiology in Review* Circulation* Circulation Research* Clinical and Experimental Hypertension* Clinical Cardiology* EP – Europace* European Heart Journal* Heart* Heart Rhythm* International Journal of Cardiology* Journal of the American College of Cardiology* Pacing and Clinical Electrophysiology* Indian Heart Journal=== Cardiologists ===* Robert Atkins (1930–2003), known for the Atkins diet* Eugene Braunwald (born 1929), editor of ''Braunwald's Heart Disease'' and 1000+ publications* Wallace Brigden (1916–2008), identified cardiomyopathy* Manoj Durairaj (1971– ), cardiologist from Pune, India who received Pro Ecclesia et Pontifice* Willem Einthoven (1860–1927), a physiologist who built the first practical ECG and won the 1924 Nobel Prize in Physiology or Medicine (\"for the discovery of the mechanism of the electrocardiogram\")* Werner Forssmann (1904–1979), who infamously performed the first human catheterization on himself that led to him being let go from Berliner Charité Hospital, quitting cardiology as a speciality, and then winning the 1956 Nobel Prize in Physiology or Medicine (\"for their discoveries concerning heart catheterization and pathological changes in the circulatory system\")* Andreas Gruentzig (1939–1985), first developed balloon angioplasty* William Harvey (1578–1657), wrote ''Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus'' that first described the closed circulatory system and whom Forssmann described as founding cardiology in his Nobel lecture* Murray S. Hoffman (1924–2018) As president of the Colorado Heart Association, he initiated one of the first jogging programs promoting cardiac health* Max Holzmann (1899–1994), co-founder of the Swiss Society of Cardiology, president from 1952 to 1955* Samuel A. Levine (1891–1966), recognized the sign known as Levine's sign as well as the current grading of the intensity of heart murmurs, known as the Levine scale* Henry Joseph Llewellyn \"Barney\" Marriott (1917–2007), ECG interpretation and ''Practical Electrocardiography''* Bernard Lown (1921–2021), original developer of the defibrillator* Woldemar Mobitz (1889–1951), described and classified the two types of second-degree atrioventricular block often called \"Mobitz Type I\" and \"Mobitz Type II\"* Jacqueline Noonan (1928–2020), discoverer of Noonan syndrome that is the top syndromic cause of congenital heart disease* John Parkinson (1885–1976), known for Wolff–Parkinson–White syndrome* Helen B. Taussig (1898–1986), founder of pediatric cardiology and extensively worked on blue baby syndrome* Paul Dudley White (1886–1973), known for Wolff–Parkinson–White syndrome* Fredrick Arthur Willius (1888–1972), founder of the cardiology department at the Mayo Clinic and an early pioneer of electrocardiography* Louis Wolff (1898–1972), known for Wolff–Parkinson–White syndrome* Karel Frederik Wenckebach (1864–1940), first described what is now called type I second-degree atrioventricular block in 1898" ], [ "See also", "* Glossary of medicine* List of cardiac pharmaceutical agents* Outline of cardiology" ], [ "References" ], [ "Sources", "* *" ], [ "External links", "* American Heart Association" ] ]

[ [ "Capcom" ], [ "Introduction", " is a Japanese video game company.", "It has created a number of multi-million-selling game franchises, with its most commercially successful being ''Resident Evil'', ''Monster Hunter'', ''Street Fighter'', ''Mega Man'', ''Devil May Cry'', ''Dead Rising'', ''Ace Attorney'', and ''Marvel vs. Capcom''.", "Mega Man himself serves as the official mascot of the company.", "Established in 1979, it has become an international enterprise with subsidiaries in East Asia (Hong Kong), Europe (London, England), and North America (San Francisco, California)." ], [ "History", "Capcom's predecessor, I.R.M.", "Corporation, was founded on May 30, 1979 by Kenzo Tsujimoto, who was still president of Irem Corporation when he founded I.R.M.", "He worked concomitantly in both companies until leaving the former in 1983.The original companies that spawned Capcom's Japan branch were I.R.M.", "and its subsidiary Japan Capsule Computers Co., Ltd., both of which were devoted to the manufacture and distribution of electronic game machines.", "The two companies underwent a name change to Sanbi Co., Ltd. in September 1981.On June 11, 1983, Tsujimoto established Capcom Co., Ltd. for the purpose of taking over the internal sales department.In January 1989, Capcom Co., Ltd. merged with Sanbi Co., Ltd., resulting in the current Japan branch.", "The name Capcom is a clipped compound of \"'''Cap'''sule '''Com'''puters\", a term coined by the company for the arcade machines it solely manufactured in its early years, designed to set themselves apart from personal computers that were becoming widespread.", "\"Capsule\" alludes to how Capcom likened its game software to \"a capsule packed to the brim with gaming fun\", and to the company's desire to protect its intellectual property with a hard outer shell, preventing illegal copies and inferior imitations.Capcom's first product was the medal game ''Little League'' (1983).", "It released its first arcade video game, ''Vulgus'' (May 1984).", "Starting with the arcade hit ''1942'' (1984), they began designing games with international markets in mind.", "The successful 1985 arcade games ''Commando'' and ''Ghosts 'n Goblins'' have been credited as the products \"that shot Capcom to 8-bit silicon stardom\" in the mid-1980s.", "Starting with ''Commando'' (late 1985), Capcom began licensing their arcade games for release on home computers, notably to British software houses Elite Systems and U.S. Gold in the late 1980s.Beginning with a Nintendo Entertainment System port of ''1942'' (published in Dec. 1985), the company ventured into the market of home console video games, which would eventually become its main business.", "The Capcom USA division had a brief stint in the late 1980s as a video game publisher for Commodore 64 and IBM PC DOS computers, although development of these arcade ports was handled by other companies.", "Capcom created home video game franchises, including ''Resident Evil'' in 1996, while their highest-grossing title is the fighting game ''Street Fighter II'' (1991), driven largely by its success in arcades.In the late 1980s, Capcom was on the verge of bankruptcy when the development of a strip Mahjong game called ''Mahjong Gakuen'' started.", "It outsold ''Ghouls 'n Ghosts'', the eighth highest-grossing arcade game of 1989 in Japan, and is credited with saving the company from financial crisis.Capcom has been noted as the last major publisher to be committed to 2D games, though it was not entirely by choice.", "The company's commitment to the Super Nintendo Entertainment System as its platform of choice caused them to lag behind other leading publishers in developing 3D-capable arcade boards.", "Also, the 2D animated cartoon-style graphics seen in games such as ''Darkstalkers: The Night Warriors'' and ''X-Men: Children of the Atom'' proved popular, leading Capcom to adopt them as a signature style and use them in more games.In 1990, Capcom entered the bowling industry with ''Bowlingo''.", "It was a coin-operated, electro-mechanical, fully automated mini ten-pin bowling installation.", "It was smaller than a standard bowling alley, designed to be smaller and cheaper for amusement arcades.", "''Bowlingo'' drew significant earnings in North America upon release in 1990.In 1994, Capcom adapted its ''Street Fighter'' series of fighting games into a film of the same name.", "While commercially successful, it was critically panned.", "A 2002 adaptation of its ''Resident Evil'' series faced similar criticism but was also successful in theaters.", "The company sees films as a way to build sales for its video games.Capcom partnered with Nyu Media in 2011 to publish and distribute the Japanese independent (dōjin soft) games that Nyu localized into the English language.", "The company works with the Polish localization company QLOC to port Capcom's games to other platforms; notably, examples are ''DmC: Devil May Cry''s PC version and its PlayStation 4 and Xbox One remasters, ''Dragon's Dogma''s PC version, and ''Dead Rising''s version on PlayStation 4, Xbox One, and PC.In 2012, Capcom came under criticism for controversial sales tactics, such as the implementation of disc-locked content, which requires players to pay for additional content that is already available within the game's files, most notably in ''Street Fighter X Tekken''.", "The company defended the practice.", "It has also been criticized for other business decisions, such as not releasing certain games outside of Japan (most notably the ''Sengoku Basara'' series), abruptly cancelling anticipated projects (most notably ''Mega Man Legends 3''), and shutting down Clover Studio.On August 27, 2014, Capcom filed a patent infringement lawsuit against Koei Tecmo Games at the Osaka District Court for 980 million yen in damage.", "Capcom claimed Koei Tecmo infringed a patent it obtained in 2002 regarding a play feature in video games.In 2015, the PlayStation 4 version of ''Ultra Street Fighter IV'' was pulled from the Capcom Pro Tour due to numerous technical issues and bugs.", "In 2016, Capcom released ''Street Fighter V'' with very limited single player content.", "At launch, there were stability issues with the game's network that booted players mid-game even when they were not playing in an online mode.", "''Street Fighter V'' failed to meet its sales target of 2 million in March 2016.On November 2, 2020, the company reported that its servers were affected by ransomware, scrambling its data, and the threat actors, the Ragnar Locker hacker group, had allegedly stolen 1TB of sensitive corporate data and were blackmailing Capcom to pay them to remove the ransomware.", "By mid-November, the group began putting information from the hack online, which included contact information for up to 350,000 of the company's employees and partners, as well as plans for upcoming games, indicating that Capcom opted to not pay the group.", "Capcom affirmed that no credit-card or other sensitive financial information was obtained in the hack.In 2021, Capcom removed appearances of the Rising Sun Flag from their rerelease of ''Street Fighter II''.", "Although Capcom did not provide an official explanation for the flag's removal, due to the flag-related controversy, it is speculated that it was done so to avoid offending segments of the international gaming community.Artist and author Judy A. Juracek filed a lawsuit in June 2021 against Capcom for copyright infringement.", "In the court filings, she asserted Capcom had used images from her 1996 book ''Surfaces'' in their cover art and other assets for ''Resident Evil 4'', ''Devil May Cry'' and other games.", "This was discovered due to the 2020 Capcom data breach, with several files and images matching those that were included within the book's companion CD-ROM.", "The court filings noted one image file of a metal surface, named ME0009 in Capcom's files, to have the same exact name on the book's CD-ROM.", "Juracek was seeking over in damages and $2,500 to $25,000 in false copyright management for each photograph Capcom used.", "Before a court date could be made, the matter was settled \"amicably\" in February 2022.It comes on the heels of Capcom being accused by Dutch movie director Richard Raaphorst of copying the monster design of his movie ''Frankenstein's Army'' into their game ''Resident Evil Village''.In February 2022, it was reported by Bloomberg that Saudi Arabia's Public Investment Fund had purchased a 5% stake in Capcom, for an approximate value of US$332 million.In July 2023, Capcom acquired Tokyo-based computer graphics studio Swordcanes Studio." ], [ "Corporate structure", "===Development divisions===In its beginning few years, Capcom's Japan branch had three development groups referred to as \"Planning Rooms\", led by Tokuro Fujiwara, Takashi Nishiyama and Yoshiki Okamoto.", "Later, games developed internally were created by several numbered \"Production Studios\", each assigned to different games.", "Starting in 2002, the development process was reformed to better share technologies and expertise, and the individual studios were gradually restructured into bigger departments responsible for different tasks.", "While there are self-contained departments for the creation of arcade, pachinko and pachislot, online, and mobile games, the Consumer Games R&D Division is an amalgamation of subsections in charge of game development stages.Capcom has two internal Consumer Games Development divisions:* Division 1, headed by Jun Takeuchi, develops ''Resident Evil'', ''Mega Man'', ''Devil May Cry'', ''Dead Rising'', and other major franchises (usually targeting global audiences).", "* Division 2, headed by Ryozo Tsujimoto, develops ''Ace Attorney'', ''Onimusha'', ''Sengoku Basara'', ''Ōkami'', and other franchises with more traditional IP (usually targeting audiences in Asia) alongside online-focused franchises such as ''Monster Hunter'', ''Street Fighter'', ''Marvel vs. Capcom'', and ''Lost Planet''.In addition to these teams, Capcom commissions outside development studios to ensure a steady output of titles.", "However, following poor sales of ''Dark Void'' and ''Bionic Commando'', its management has decided to limit outsourcing to sequels and newer versions of installments in existing franchises, reserving the development of original titles for its in-house teams.", "The production of games, budgets, and platform support are decided on in development approval meetings, attended by the company management and the marketing, sales and quality control departments.Although the company often relies on existing franchises, it has also published and developed several titles for the Xbox 360, PlayStation 3, and Wii based on original intellectual property: ''Lost Planet: Extreme Condition'', ''Dead Rising'', ''Dragon's Dogma'', ''Asura's Wrath'', and ''Zack and Wiki''.", "During this period, Capcom also helped publish several original titles from up-and-coming Western developers, including ''Remember Me'', ''Dark Void'', and ''Spyborgs'', titles other publishers were not willing to gamble on.", "Other games of note are the titles ''Ōkami'', ''Ōkamiden'', and ''Ghost Trick: Phantom Detective''.===Branches and subsidiaries===Capcom Co., Ltd.'s head office building and R&D building are in Chūō-ku, Osaka.", "The parent company also has a branch office in the Shinjuku Mitsui Building in Nishi-Shinjuku, Shinjuku, Tokyo; and the Ueno Facility, a branch office in Iga, Mie Prefecture.The international Capcom Group encompasses 12 subsidiaries in Japan, rest of East Asia, North America, and Europe.===Game-related media===In addition to home, online, mobile, arcade, pachinko, and pachislot games, Capcom publishes strategy guides; maintains its own ''Plaza Capcom'' arcade centers in Japan; and licenses its franchise and character properties for tie-in products, movies, television series, and stage performances.Suleputer, an in-house marketing and music label established in cooperation with Sony Music Entertainment Intermedia in 1998, publishes CDs, DVDs, and other media based on Capcom's games.", "Captivate (renamed from Gamers Day in 2008), an annual private media summit, is traditionally used for new game and business announcements." ], [ "Technology", "* MT Framework* Panta Rhei (game engine)* RE Engine" ], [ "Game sales", "+Capcom's top 10 multi-million selling franchises(as of December 31, 2023)FranchiseFirst releaseSales ()''Resident Evil''1996154.0''Monster Hunter''200497.0''Street Fighter''198753.0''Mega Man''198741.0 ''Devil May Cry''200130.0''Dead Rising''200616.0''Ace Attorney''200111.0''Marvel vs. Capcom''199611.0''Onimusha''20018.6''Dragon's Dogma''20128.4Capcom started its ''Street Fighter'' franchise in 1987.The series of fighting games are among the most popular in their genre.", "Having sold over 50 million copies, it is one of Capcom's flagship franchises.", "The company also introduced its ''Mega Man'' series in 1987, which has sold over 40 million copies.The company released the first entry in its ''Resident Evil'' survival horror series in 1996, which become its most successful game series, selling over 150 million copies.", "After releasing the second entry in the ''Resident Evil'' series, Capcom began a ''Resident Evil'' game for PlayStation 2.As it was significantly different from the existing series' games, Capcom decided to spin it into its own series, ''Devil May Cry''.", "The first three entries were exclusively for PlayStation 2; further entries were released for non-Sony consoles.", "The entire series has sold 30 million copies.", "Capcom began its ''Monster Hunter'' series in 2004, which has sold over 90 million copies on a variety of consoles.Capcom compiles a \"Platinum Titles\" list, updated quarterly, of its games that have sold over one million copies.", "It contains over 100 video games.", "This table shows the top ten titles, by sold copies, as of December 31, 2023.TitleRelease datePlatform(s) consideredSales ()''Monster Hunter: World''PlayStation 4, Xbox One, PC19.60''Monster Hunter Rise''Nintendo Switch, PlayStation 4, PlayStation 5, Xbox One, Xbox Series X/S, PC14.20''Resident Evil 2''PlayStation 4, PlayStation 5, Xbox One, Xbox Series X/S, Nintendo Switch, PC13.60''Resident Evil 7: Biohazard''PlayStation 4, PlayStation 5, Xbox One, Xbox Series X/S, Nintendo Switch, PC13.00''Monster Hunter World: Iceborne''PlayStation 4, Xbox One, PC11.60''Resident Evil Village''PlayStation 4, PlayStation 5, Xbox One, Xbox Series X/S, Nintendo Switch, PC9.30''Resident Evil 5''PlayStation 3, Xbox 3609.00''Resident Evil 6''PlayStation 3, Xbox 3609.00''Resident Evil 3''PlayStation 4, PlayStation 5, Xbox One, Xbox Series X/S, Nintendo Switch, PC8.40''Devil May Cry 5''PlayStation 4, Xbox One, PC7.80" ], [ "See also", "===Articles===*Capcom Cup*Capcom Five*DreamHack*Evolution Championship Series===Companies founded by ex-Capcom employees===NameFoundationAffiliationArikaNovember 1, 1995Founded by Akira NishitaniCrafts & MeisterJune 1, 2004Founded by Noritaka Funamizu and Katsuhiro SudoDimpsMarch 6, 2000Founded by Takashi Nishiyama and Hiroshi MatsumotoGame RepublicJuly 1, 2003Founded by Yoshiki OkamotoInti CreatesMay 8, 1996Founded by Takuya AizuLevel-5 ComceptDecember 1, 2010Founded by Keiji Inafune as ComceptPlatinumGamesOctober 1, 2007Founded by Shinji Mikami, Atsushi Inaba, Hideki Kamiya, and Tatsuya MinamiTango GameworksMarch 1, 2010Founded by Shinji MikamiUTV Ignition GamesSeptember 26, 2001Sawaki Takeyasu joined Ignition Tokyo, a subsidiary of UTV Ignition Games" ], [ "References" ], [ "External links", "* Official website" ] ]

[ [ "History of Cambodia" ], [ "Introduction", "The '''history of Cambodia''', a country in mainland Southeast Asia, can be traced back to Indian civilization.", "Detailed records of a political structure on the territory of what is now Cambodia first appear in Chinese annals in reference to Funan, a polity that encompassed the southernmost part of the Indochinese peninsula during the 1st to 6th centuries.", "Centered at the lower Mekong, Funan is noted as the oldest regional Hindu culture, which suggests prolonged socio-economic interaction with maritime trading partners of the Indosphere in the west.", "By the 6th century a civilization, called Chenla or Zhenla in Chinese annals, firmly replaced Funan, as it controlled larger, more undulating areas of Indochina and maintained more than a singular centre of power.The Khmer Empire was established by the early 9th century.", "Sources refer here to a mythical initiation and consecration ceremony to claim political legitimacy by founder Jayavarman II at Mount Kulen (Mount Mahendra) in 802 CE.", "A succession of powerful sovereigns, continuing the Hindu devaraja cult tradition, reigned over the classical era of Khmer civilization until the 11th century.", "A new dynasty of provincial origin introduced Buddhism, which according to some scholars resulted in royal religious discontinuities and general decline.", "The royal chronology ends in the 14th century.", "Great achievements in administration, agriculture, architecture, hydrology, logistics, urban planning and the arts are testimony to a creative and progressive civilisation - in its complexity a cornerstone of Southeast Asian cultural legacy.The decline continued through a transitional period of approximately 100 years followed by the Middle Period of Cambodian history, also called the Post-Angkor Period, beginning in the mid 15th century.", "Although the Hindu cults had by then been all but replaced, the monument sites at the old capital remained an important spiritual centre.Yet since the mid 15th century the core population steadily moved to the east and – with brief exceptions – settled at the confluence of the Mekong and Tonle Sap rivers at Chaktomuk, Longvek and Oudong.Maritime trade was the basis for a very prosperous 16th century.", "But, as a result foreigners – Muslim Malays and Cham, Christian European adventurers and missionaries – increasingly disturbed and influenced government affairs.", "Ambiguous fortunes, a robust economy on the one hand and a disturbed culture and compromised royalty on the other were constant features of the Longvek era.By the 15th century, the Khmers' traditional neighbours, the Mon people in the west and the Cham people in the east had gradually been pushed aside or replaced by the resilient Siamese/Thai and Annamese/Vietnamese, respectively.", "These powers had perceived, understood and increasingly followed the imperative of controlling the lower Mekong basin as the key to control all Indochina.", "A weak Khmer kingdom only encouraged the strategists in Ayutthaya (later in Bangkok) and in Huế.", "Attacks on and conquests of Khmer royal residences left sovereigns without a ceremonial and legitimate power base.", "Interference in succession and marriage policies added to the decay of royal prestige.", "Oudong was established in 1601 as the last royal residence of the Middle Period.The 19th-century arrival of then technologically more advanced and ambitious European colonial powers with concrete policies of global control put an end to regional feuds and as Siam/Thailand, although humiliated and on the retreat, escaped colonisation as a buffer state, Vietnam was to be the focal point of French colonial ambition.", "Cambodia, although largely neglected, had entered the Indochinese Union as a perceived entity and was capable to carry and reclaim its identity and integrity into modernity.After 80 years of colonial hibernation, the brief episode of Japanese occupation during World War II, that coincided with the investiture of king Sihanouk was the opening act for the irreversible process towards re-emancipation and modern Cambodian history.The Kingdom of Cambodia (1953–70), independent since 1953, struggled to remain neutral in a world shaped by polarisation of the nuclear powers USA and Soviet Union.As the Indochinese war escalated, and Cambodia became increasingly involved, the Khmer Republic resulted in 1970.Another result was a civil war which by 1975, ended with the takeover by the Khmer Rouge.", "Cambodia endured its darkest hour – Democratic Kampuchea and the long aftermath of Vietnamese occupation, the People's Republic of Kampuchea and the UN Mandate towards Modern Cambodia since 1993." ], [ "Prehistory and early history", "Radiocarbon dating of a cave at Laang Spean in Battambang Province, northwest Cambodia confirmed the presence of Hoabinhian stone tools from 6000–7000 BCE and pottery from 4200 BCE.", "Starting in 2009 archaeological research of the ''Franco-Cambodian Prehistoric Mission'' has documented a complete cultural sequence from 71.000 years BP to the Neolithic period in the cave.", "Finds since 2012 lead to the common interpretation, that the cave contains the archaeological remains of a first occupation by hunter and gatherer groups, followed by Neolithic people with highly developed hunting strategies and stone tool making techniques, as well as highly artistic pottery making and design, and with elaborate social, cultural, symbolic and exequial practices.", "Cambodia participated in the Maritime Jade Road, which was in place in the region for 3,000 years, beginning in 2000 BCE to 1000 CE.Skulls and human bones found at Samrong Sen in Kampong Chhnang Province date from 1500 BCE.", "Heng Sophady (2007) has drawn comparisons between Samrong Sen and the circular earthwork sites of eastern Cambodia.", "These people may have migrated from South-eastern China to the Indochinese Peninsula.", "Scholars trace the first cultivation of rice and the first bronze making in Southeast Asia to these people.2010 Examination of skeletal material from graves at Phum Snay in north-west Cambodia revealed an exceptionally high number of injuries, especially to the head, likely to have been caused by interpersonal violence.", "The graves also contain a quantity of swords and other offensive weapons used in conflict.The Iron Age period of Southeast Asia begins around 500 BCE and lasts until the end of the Funan era - around 500 A.D. as it provides the first concrete evidence for sustained maritime trade and socio-political interaction with India and South Asia.", "By the 1st century settlers have developed complex, organised societies and a varied religious cosmology, that required advanced spoken languages very much related to those of the present day.", "The most advanced groups lived along the coast and in the lower Mekong River valley and the delta regions in houses on stilts where they cultivated rice, fished and kept domesticated animals." ], [ "Funan Kingdom (1st century – 550/627)", "Map of Funan at around the 3rd centuryChinese annals contain detailed records of the first known organised polity, the Kingdom of Funan, on Cambodian and Vietnamese territory characterised by \"high population and urban centers, the production of surplus food...socio-political stratification and legitimized by Indian religious ideologies\".", "Centered around the lower Mekong and Bassac rivers from the first to sixth century CE with \"walled and moated cities\" such as Angkor Borei in Takeo Province and Óc Eo in modern An Giang Province, Vietnam.Early Funan was composed of loose communities, each with its own ruler, linked by a common culture and a shared economy of rice farming people in the hinterland and traders in the coastal towns, who were economically interdependent, as surplus rice production found its way to the ports.By the second century CE Funan controlled the strategic coastline of Indochina and the maritime trade routes.", "Cultural and religious ideas reached Funan via the Indian Ocean trade route.", "Trade with India had commenced well before 500 BCE as Sanskrit hadn't yet replaced Pali.", "Funan's language has been determined as to have been an early form of Khmer and its written form was Sanskrit.The territories of Eastern Wu (in green), 262 CERoman trade with India according to the ''Periplus Maris Erythraei'', 1st century CEIn the period 245–250 CE dignitaries of the Chinese Kingdom of Wu visited the Funan city Vyadharapura.", "Envoys Kang Tai and Zhu Ying defined Funan as to be a distinct Hindu culture.", "Trade with China had begun after the southward expansion of the Han Dynasty, around the 2nd century BCE Effectively Funan \"controlled strategic land routes in addition to coastal areas\" and occupied a prominent position as an \"economic and administrative hub\" between The Indian Ocean trade network and China, collectively known as the Maritime Silk Road.", "Trade routes, that eventually ended in distant Rome are corroborated by Roman and Persian coins and artefacts, unearthed at archaeological sites of 2nd and 3rd century settlements.Funan is associated with myths, such as the Kattigara legend and the Khmer founding legend in which an Indian Brahman or prince named Preah Thaong in Khmer, Kaundinya in Sanskrit and Hun-t’ien in Chinese records marries the local ruler, a princess named Nagi Soma (Lieu-Ye in Chinese records), thus establishing the first Cambodian royal dynasty.Scholars debate as to how deep the narrative is rooted in actual events and on Kaundinya's origin and status.", "A Chinese document, that underwent 4 alterations and a 3rd-century epigraphic inscription of Champa are the contemporary sources.", "Some scholars consider the story to be simply an allegory for the diffusion of Indic Hindu and Buddhist beliefs into ancient local cosmology and culture whereas some historians dismiss it chronologically.Chinese annals report that Funan reached its territorial climax in the early 3rd century under the rule of king Fan Shih-man, extending as far south as Malaysia and as far west as Burma.", "A system of mercantilism in commercial monopolies was established.", "Exports ranged from forest products to precious metals and commodities such as gold, elephants, ivory, rhinoceros horn, kingfisher feathers, wild spices like cardamom, lacquer, hides and aromatic wood.", "Under Fan Shih-man Funan maintained a formidable fleet and was administered by an advanced bureaucracy, based on a \"tribute-based economy, that produced a surplus which was used to support foreign traders along its coasts and ostensibly to launch expansionist missions to the west and south\".Historians maintain contradicting ideas about Funan's political status and integrity.", "Miriam T. Stark calls it simply Funan: The\"notion of Fu Nan as an early \"state\"...has been built largely by historians using documentary and historical evidence\" and Michael Vickery remarks: \"Nevertheless, it is...unlikely that the several ports constituted a unified state, much less an 'empire'\".", "Other sources though, imply imperial status: \"Vassal kingdoms spread to southern Vietnam in the east and to the Malay peninsula in the west\" and \"Here we will look at two empires of this period...Funan and Srivijaya\".The question of how Funan came to an end is in the face of almost universal scholarly conflict impossible to pin down.", "Chenla is the name of Funan's successor in Chinese annals, first appearing in 616/617 CEThe archaeological approach to and interpretation of the entire early historic period is considered to be a decisive supplement for future research.", "The \"Lower Mekong Archaeological Project\" focuses on the development of political complexity in this region during the early historic period.", "LOMAP survey results of 2003 to 2005, for example, have helped to determine that \"...the region's importance continued unabated throughout the pre-Angkorian period...and that at least three surveyed areas bear Angkorian-period dates and suggest the continued importance of the delta.\"" ], [ "Chenla Kingdom (6th century – 802)", "The History of the Chinese Sui dynasty contains records that a state called Chenla sent an embassy to China in 616 or 617 CE It says, that Chenla was a vassal of Funan, but under its ruler Citrasena-Mahendravarman conquered Funan and gained independence.Most of the Chinese recordings on Chenla, including that of Chenla conquering Funan, have been contested since the 1970s as they are generally based on single remarks in the Chinese annals, as author Claude Jacques emphasised the very vague character of the Chinese terms 'Funan' and 'Chenla', while more domestic epigraphic sources become available.", "Claude Jacques summarises: \"Very basic historical mistakes have been made\" because \"the history of pre-Angkorean Cambodia was reconstructed much more on the basis of Chinese records than on that of Cambodian inscriptions\" and as new inscriptions were discovered, researchers \"preferred to adjust the newly discovered facts to the initial outline rather than to call the Chinese reports into question\".The notion of Chenla's centre being in modern Laos has also been contested.", "\"All that is required is that it be inland from Funan.\"", "The most important political record of pre-Angkor Cambodia, the inscription K53 from Ba Phnom, dated 667 CE does not indicate any political discontinuity, either in royal succession of kings Rudravarman, Bhavavarman I, Mahendravarman Citrasena, Īśānavarman, and Jayavarman I or in the status of the family of officials who produced the inscription.", "Another inscription of a few years later, K44, 674 CE, commemorating a foundation in Kampot province under the patronage of Jayavarman I, refers to an earlier foundation in the time of King Raudravarma, presumably Rudravarman of Funan, and again there is no suggestion of political discontinuity.The History of the T'ang asserts that shortly after 706 the country was split into and .", "The names signify a northern and a southern half, which may conveniently be referred to as Upper and Lower Chenla.By the late 8th century Water Chenla had become a vassal of the Sailendra dynasty of Java – the last of its kings were killed and the polity incorporated into the Javanese monarchy around 790 CE.", "Land Chenla acquired independence under Jayavarman II in 802 CEAncient Chinese records mention two kings, Shrutavarman and Shreshthavarman who ruled at the capital Shreshthapura located in modern-day southern Laos.", "The immense influence on the identity of Cambodia to come was wrought by the Khmer Kingdom of Bhavapura, in the modern day Cambodian city of Kampong Thom.", "Its legacy was its most important sovereign, Ishanavarman who completely conquered the kingdom of Funan during 612–628.He chose his new capital at the Sambor Prei Kuk, naming it Ishanapura." ], [ "Khmer Empire (802–1431)", "Archers mounted on elephantsMap of South-east Asia c. 900 CE, showing the Khmer Empire in red, Champa in yellow and Haripunjaya in light green, plus additional surrounding statesThe six centuries of the Khmer Empire are characterised by unparalleled technical and artistic progress and achievements, political integrity and administrative stability.", "The empire represents the cultural and technical apogee of the Cambodian and Southeast Asian pre-industrial civilisation.Bakong, one of the earliest temple mountain in Khmer architectureThe Khmer Empire was preceded by Chenla, a polity with shifting centres of power, which was split into Land Chenla and Water Chenla in the early 8th century.", "By the late 8th century Water Chenla was absorbed by the Malays of the Srivijaya Empire and the Javanese of the Shailandra Empire and eventually incorporated into Java and Srivijaya.Jayavarman II, ruler of Land Chenla, initiates a mythical Hindu consecration ceremony at Mount Kulen (Mount Mahendra) in 802 CE, intended to proclaim political autonomy and royal legitimacy.", "As he declared himself devaraja - god-king, divinely appointed and uncontested, he simultaneously declares independence from Shailandra and Srivijaya.", "He established Hariharalaya, the first capital of the Angkorean area near the modern town of Roluos.Indravarman I (877–889) and his son and successor Yasovarman I (889–900), who established the capital Yasodharapura ordered the construction of huge water reservoirs (barays) north of the capital.", "The water management network depended on elaborate configurations of channels, ponds, and embankments built from huge quantities of clayey sand, the available bulk material on the Angkor plain.", "Dikes of the East Baray still exist today, which are more than long and wide.", "The largest component is the West Baray, a reservoir about long and across, containing approximately 50 million m3 of water.The mainland of Southeast Asia at the end of the 13th centuryRoyal administration was based on the religious idea of the Shivaite Hindu state and the central cult of the sovereign as warlord and protector – the \"Varman\".", "This centralised system of governance appointed royal functionaries to provinces.", "The Mahidharapura dynasty – its first king was Jayavarman VI (1080 to 1107), which originated west of the Dângrêk Mountains in the Mun river valley discontinued the old \"ritual policy\", genealogical traditions and crucially, Hinduism as exclusive state religion.", "Some historians relate the empires' decline to these religious discontinuities.The area that comprises the various capitals was spread out over around , it is nowadays commonly called Angkor.", "The combination of sophisticated wet-rice agriculture, based on an engineered irrigation system and the Tonlé Sap's spectacular abundance in fish and aquatic fauna, as protein source guaranteed a regular food surplus.", "Recent Geo-surveys have confirmed that Angkor maintained the largest pre-industrial settlement complex worldwide during the 12th and 13th centuries – some three quarters of a million people lived there.", "Sizeable contingents of the public workforce were to be redirected to monument building and infrastructure maintenance.", "A growing number of researchers relates the progressive over-exploitation of the delicate local eco-system and its resources alongside large scale deforestation and resulting erosion to the empires' eventual decline.Under king Suryavarman II (1113–1150) the empire reached its greatest geographic extent as it directly or indirectly controlled Indochina, the Gulf of Thailand and large areas of northern maritime Southeast Asia.", "Suryavarman II commissioned the temple of Angkor Wat, built in a period of 37 years, its five towers representing Mount Meru is considered to be the most accomplished expression of classical Khmer architecture.", "However, territorial expansion ended when Suryavarman II was killed in battle attempting to invade Đại Việt.", "It was followed by a period of dynastic upheaval and a Cham invasion that culminated in the sack of Angkor in 1177.Portrait statue of Jayavarman VIIKing Jayavarman VII (reigned 1181–1219) is generally considered to be Cambodia's greatest King.", "A Mahayana Buddhist, he initiates his reign by striking back against Champa in a successful campaign.", "During his nearly forty years in power he becomes the most prolific monument builder, who establishes the city of Angkor Thom with its central temple the Bayon.", "Further outstanding works are attributed to him – Banteay Kdei, Ta Prohm, Neak Pean and Sra Srang.", "The construction of an impressive number of utilitarian and secular projects and edifices, such as maintenance of the extensive road network of Suryavarman I, in particular the royal road to Phimai and the many rest houses, bridges and hospitals make Jayavarman VII unique among all imperial rulers.In August 1296, the Chinese diplomat Zhou Daguan arrived at Angkor and remained at the court of king Srindravarman until July 1297.He wrote a detailed report, ''The Customs of Cambodia'', on life in Angkor.", "His portrayal is one of the most important sources of understanding historical Angkor as the text offers valuable information on the everyday life and the habits of the inhabitants of Angkor.The last Sanskrit inscription is dated 1327, and records the succession of Indrajayavarman by Jayavarman IX Parameshwara (1327–1336).The empire was an agrarian state that consisted essentially of three social classes, the elite, workers and slaves.", "The elite included advisers, military leaders, courtiers, priests, religious ascetics and officials.", "Workers included agricultural labourers and also a variety of craftsman for construction projects.", "Slaves were often captives from military campaigns or distant villages.", "Coinage did not exist and the barter economy was based on agricultural produce, principally rice, with regional trade as an insignificant part of the economy." ], [ "Post-Angkor Period of Cambodia (1431–1863)", "Longvek, the former capital of CambodiaFlag of Cambodia pre-1864The term \"Post-Angkor Period of Cambodia\", also the \"Middle Period\" refers to the historical era from the early 15th century to 1863, the beginning of the French Protectorate of Cambodia.", "Reliable sources – particularly for the 15th and 16th century – are very rare.", "A conclusive explanation that relates to concrete events manifesting the decline of the Khmer Empire has not yet been produced.", "However, most modern historians contest that several distinct and gradual changes of religious, dynastic, administrative and military nature, environmental problems and ecological imbalance coincided with shifts of power in Indochina and must all be taken into account to make an interpretation.", "In recent years, focus has notably shifted towards studies on climate changes, human–environment interactions and the ecological consequences.Epigraphy in temples, ends in the third decade of the fourteenth, and does not resume until the mid-16th century.", "Recording of the Royal Chronology discontinues with King Jayavarman IX Parameshwara (or Jayavarma-Paramesvara) – there exists not a single contemporary record of even a king's name for over 200 years.", "Construction of monumental temple architecture had come to a standstill after Jayavarman VII's reign.", "According to author Michael Vickery there only exist external sources for Cambodia's 15th century, the Chinese Ming Shilu annals and the earliest Royal Chronicle of Ayutthaya.", "Wang Shi-zhen (王世貞), a Chinese scholar of the 16th century, remarked: \"The official historians are unrestrained and are skilful at concealing the truth; but the memorials and statutes they record and the documents they copy cannot be discarded.", "\"The central reference point for the entire 15th century is a Siamese intervention of some undisclosed nature at the capital Yasodharapura (Angkor Thom) around the year 1431.Historians relate the event to the shift of Cambodia's political centre southward to the region of Phnom Penh, Longvek and later Oudong.1780 map of Cambodia and Southeast AsiaSources for the 16th century are more numerous.", "The kingdom is centred at the Mekong, prospering as an integral part of the Asian maritime trade network, via which the first contact with European explorers and adventurers does occur.", "Wars with the Siamese result in loss of territory and eventually the conquest of the capital Longvek in 1594.Richard Cocks, of the East India Company established trade with Cochin, China, and Cambodia by 1618, but the Cambodia commerce was not authorized by the directors in London and was short-lived until it was revived in 1651, again without authorization.", "The Vietnamese on their \"Southward March\" reach Prei Nokor/Saigon at the Mekong Delta in the 17th century.", "This event initiates the slow process of Cambodia losing access to the seas and independent marine trade.Siamese and Vietnamese dominance intensified during the 17th and 18th century, resulting in frequent displacements of the seat of power as the Khmer royal authority decreased to the state of a vassal.", "In the early 19th century with dynasties in Vietnam and Siam firmly established, Cambodia was placed under joint suzerainty, having lost its national sovereignty.", "British agent John Crawfurd states: \"...the King of that ancient Kingdom is ready to throw himself under the protection of any European nation...\" To save Cambodia from being incorporated into Vietnam and Siam, the Cambodians entreated the aid of the Luzones/Lucoes (Filipinos from Luzon-Philippines) that previously participated in the Burmese-Siamese wars as mercenaries.", "When the embassy arrived in Luzon, the rulers were now Spaniards, so they asked them for aid too, together with their Latin American troops imported from Mexico, in order to restore the then Christianised King, Satha II, as monarch of Cambodia, this, after a Thai/Siamese invasion was repelled.", "However that was only temporary.", "Nevertheless, the future King, Ang Duong, also enlisted the aid of the French who were allied to the Spanish (As Spain was ruled by a French royal dynasty the Bourbons).", "The Cambodian king agreed to colonial France's offers of protection in order to restore the existence of the Cambodian monarchy, which took effect with King Norodom Prohmbarirak signing and officially recognising the French protectorate on 11 August 1863." ], [ "French colonial period (1863–1953)", "In August 1863 King Norodom signed an agreement with the French placing the kingdom under the protection of France.", "The original treaty left Cambodian sovereignty intact, but French control gradually increased, with important landmarks in 1877, 1884, and 1897, until by the end of the century the king's authority no longer existed outside the palace.", "Norodom died in 1904, and his two successors, Sisowath and Monivong, were content to allow the French to control the country, but in 1940 France was defeated in a brief border war with Thailand and forced to surrender the provinces of Battambang and Angkor (the ancient site of Angkor itself was retained).", "King Monivong died in April 1941, and the French placed the obscure Prince Sihanouk on the throne as king, believing that the inexperienced 18-year old would be more pliable than Monivong's middle-aged son, Prince Monireth.Cambodia's situation at the end of the war was chaotic.", "The Free French, under General Charles de Gaulle, were determined to recover Indochina, though they offered Cambodia and the other Indochinese protectorates a carefully circumscribed measure of self-government.", "Convinced that they had a \"civilizing mission\", they envisioned Indochina's participation in a French Union of former colonies that shared the common experience of French culture." ], [ "Administration of Sihanouk (1953–70)", "On 9 March 1945, during the Japanese occupation of Cambodia, young king Norodom Sihanouk proclaimed an independent Kingdom of Kampuchea, following a formal request by the Japanese.", "Shortly thereafter the Japanese government nominally ratified the independence of Cambodia and established a consulate in Phnom Penh.", "The new government did away with the romanization of the Khmer language that the French colonial administration was beginning to enforce and officially reinstated the Khmer script.", "This measure taken by the short-lived governmental authority would be popular and long-lasting, for since then no government in Cambodia has tried to romanise the Khmer language again.After Allied military units entered Cambodia, the Japanese military forces present in the country were disarmed and repatriated.", "The French were able to reimpose the colonial administration in Phnom Penh in October the same year.Coronation of Norodom Sihanouk in 1941Norodom Sihanouk and his wife in Indonesia, 1964Sihanouk's \"royal crusade for independence\" resulted in grudging French acquiescence to his demands for a transfer of sovereignty.", "A partial agreement was struck in October 1953.Sihanouk then declared that independence had been achieved and returned in triumph to Phnom Penh.", "As a result of the 1954 Geneva Conference on Indochina, Cambodia was able to bring about the withdrawal of the Viet Minh troops from its territory and to withstand any residual impingement upon its sovereignty by external powers.Neutrality was the central element of Cambodian foreign policy during the 1950s and 1960s.", "By the mid-1960s, parts of Cambodia's eastern provinces were serving as bases for North Vietnamese Army and National Liberation Front (NVA/NLF) forces operating against South Vietnam, and the port of Sihanoukville was being used to supply them.", "As NVA/VC activity grew, the United States and South Vietnam became concerned, and in 1969, the United States began a 14-month-long series of bombing raids targeted at NVA/VC elements, contributing to destabilisation.", "The bombing campaign took place no further than ten, and later inside the Cambodian border, areas where the Cambodian population had been evicted by the NVA.", "Prince Sihanouk, fearing that the conflict between communist North Vietnam and South Vietnam might spill over to Cambodia, publicly opposed the idea of a bombing campaign by the United States along the Vietnam–Cambodia border and inside Cambodian territory.", "However, Peter Rodman claimed, \"Prince Sihanouk complained bitterly to us about these North Vietnamese bases in his country and invited us to attack them\".", "In December 1967 ''Washington Post'' journalist Stanley Karnow was told by Sihanouk that if the US wanted to bomb the Vietnamese communist sanctuaries, he would not object, unless Cambodians were killed.", "The same message was conveyed to US President Johnson's emissary Chester Bowles in January 1968.So the US had no real motivation to overthrow Sihanouk.", "However, Prince Sihanouk wanted Cambodia to stay out of the North Vietnam–South Vietnam conflict and was very critical of the United States government and its allies (the South Vietnamese government).", "Prince Sihanouk, facing internal struggles of his own, due to the rise of the Khmer Rouge, did not want Cambodia to be involved in the conflict.", "Sihanouk wanted the United States and its allies (South Vietnam) to keep the war away from the Cambodian border.", "Sihanouk did not allow the United States to use Cambodian air space and airports for military purposes.", "This upset the United States greatly and contributed to their view of Prince Sihanouk as a North Vietnamese sympathiser and a thorn on the United States.", "However, declassified documents indicate that, as late as March 1970, the Nixon administration was hoping to garner \"friendly relations\" with Sihanouk.Throughout the 1960s, domestic Cambodian politics became polarised.", "Opposition to the government grew within the middle class and leftists including Paris-educated leaders like Son Sen, Ieng Sary, and Saloth Sar (later known as Pol Pot), who led an insurgency under the clandestine Communist Party of Kampuchea (CPK).", "Sihanouk called these insurgents the Khmer Rouge, literally the \"Red Khmer\".", "But the 1966 national assembly elections showed a significant swing to the right, and General Lon Nol formed a new government, which lasted until 1967.During 1968 and 1969, the insurgency worsened.", "However, members of the government and army, who resented Sihanouk's ruling style as well as his tilt away from the United States, did have a motivation to overthrow him." ], [ "Khmer Republic and the War (1970–75)", "Lon NolWhile visiting Beijing in 1970 Sihanouk was ousted by a military coup led by Prime Minister General Lon Nol and Prince Sisowath Sirik Matak in the early hours of 18 March 1970.However, as early as 12 March 1970, the CIA Station Chief told Washington that based on communications from Sirik Matak, Lon Nol's cousin, that \"the (Cambodian) army was ready for a coup\".", "Lon Nol assumed power after the military coup and immediately allied Cambodia with the United States.", "Son Ngoc Thanh, an opponent of Pol Pot, announced his support for the new government.", "On 9 October, the Cambodian monarchy was abolished, and the country was renamed the Khmer Republic.", "The new regime immediately demanded that the Vietnamese communists leave Cambodia.Hanoi rejected the new republic's request for the withdrawal of NVA troops.", "In response, the United States moved to provide material assistance to the new government's armed forces, which were engaged against both CPK insurgents and NVA forces.", "The North Vietnamese and Viet Cong forces, desperate to retain their sanctuaries and supply lines from North Vietnam, immediately launched armed attacks on the new government.", "The North Vietnamese quickly overran large parts of eastern Cambodia, reaching to within of Phnom Penh.", "The North Vietnamese turned the newly won territories over to the Khmer Rouge.", "The king urged his followers to help in overthrowing this government, hastening the onset of civil war.Norodom Sihanouk and his wife with Nicolae Ceauşescu and his wife Elena Ceauşescu, 1974In April 1970, US President Richard Nixon announced to the American public that US and South Vietnamese ground forces had entered Cambodia in a campaign aimed at destroying NVA base areas in Cambodia (see Cambodian Incursion).", "The US had already been bombing Vietnamese positions in Cambodia for well over a year by that point.", "Although a considerable quantity of equipment was seized or destroyed by US and South Vietnamese forces, containment of North Vietnamese forces proved elusive.The Khmer Republic's leadership was plagued by disunity among its three principal figures: Lon Nol, Sihanouk's cousin Sirik Matak, and National Assembly leader In Tam.", "Lon Nol remained in power in part because none of the others were prepared to take his place.", "In 1972, a constitution was adopted, a parliament elected, and Lon Nol became president.", "But disunity, the problems of transforming a 30,000-man army into a national combat force of more than 200,000 men, and spreading corruption weakened the civilian administration and army.Sisowath Sirik Matak with President Richard NixonThe Khmer Rouge insurgency inside Cambodia continued to grow, aided by supplies and military support from North Vietnam.", "Pol Pot and Ieng Sary asserted their dominance over the Vietnamese-trained communists, many of whom were purged.", "At the same time, the Khmer Rouge (CPK) forces became stronger and more independent of their Vietnamese patrons.", "By 1973, the CPK were fighting battles against government forces with little or no North Vietnamese troop support, and they controlled nearly 60% of Cambodia's territory and 25% of its population.The government made three unsuccessful attempts to enter into negotiations with the insurgents, but by 1974, the CPK was operating openly as divisions, and some of the NVA combat forces had moved into South Vietnam.", "Lon Nol's control was reduced to small enclaves around the cities and main transportation routes.", "More than two million refugees from the war lived in Phnom Penh and other cities.On New Year's Day 1975, Communist troops launched an offensive which, in 117 days of the hardest fighting of the war, caused the collapse of the Khmer Republic.", "Simultaneous attacks around the perimeter of Phnom Penh pinned down Republican forces, while other CPK units overran fire bases controlling the vital lower Mekong resupply route.", "A US-funded airlift of ammunition and rice ended when Congress refused additional aid for Cambodia.", "The Lon Nol government in Phnom Penh surrendered on 17 April 1975, just five days after the US mission evacuated Cambodia.=== Foreign involvement in the rise of the Khmer Rouge ===An aerial view of bomb craters in Cambodia (2014)The relationship between the massive carpet bombing of Cambodia by the United States and the growth of the Khmer Rouge, in terms of recruitment and popular support, has been a matter of interest to historians.", "Some historians, including Michael Ignatieff, Adam Jones and Greg Grandin, have cited the United States intervention and bombing campaign (spanning 1965–1973) as a significant factor which lead to increased support for the Khmer Rouge among the Cambodian peasantry.", "According to Ben Kiernan, the Khmer Rouge \"would not have won power without U.S. economic and military destabilization of Cambodia. ...", "It used the bombing's devastation and massacre of civilians as recruitment propaganda and as an excuse for its brutal, radical policies and its purge of moderate communists and Sihanoukists.\"", "Pol Pot biographer David P. Chandler writes that the bombing \"had the effect the Americans wanted – it broke the Communist encirclement of Phnom Penh\", but it also accelerated the collapse of rural society and increased social polarization.", "Peter Rodman and Michael Lind claimed that the United States intervention saved the Lon Nol regime from collapse in 1970 and 1973.Craig Etcheson acknowledged that U.S. intervention increased recruitment for the Khmer Rouge but disputed that it was a primary cause of the Khmer Rouge victory.", "William Shawcross wrote that the United States bombing and ground incursion plunged Cambodia into the chaos that Sihanouk had worked for years to avoid.By 1973, Vietnamese support of the Khmer Rouge had largely disappeared.", "China \"armed and trained\" the Khmer Rouge both during the civil war and the years afterward.Owing to Chinese, U.S., and Western support, the Khmer Rouge-dominated Coalition Government of Democratic Kampuchea (CGDK) held Cambodia's UN seat until 1993, long after the Cold War had ended.", "China has defended its ties with the Khmer Rouge.", "Chinese Foreign Ministry spokeswoman Jiang Yu said that \"the government of Democratic Kampuchea had a legal seat at the United Nations, and had established broad foreign relations with more than 70 countries\"." ], [ "Democratic Kampuchea (Khmer Rouge era) (1975–79)", "Flag of Democratic KampucheaFlag of the Communist Party of KampucheaImmediately after its victory, the CPK ordered the evacuation of all cities and towns, sending the entire urban population into the countryside to work as farmers, as the CPK was trying to reshape society into a model that Pol Pot had conceived.The new government sought to completely restructure Cambodian society.", "Remnants of the old society were abolished and religion was suppressed.", "Agriculture was collectivised, and the surviving part of the industrial base was abandoned or placed under state control.", "Cambodia had neither a currency nor a banking system.Within the CPK, the Paris-educated leadership—Pol Pot, Ieng Sary, Nuon Chea, and Son Sen—were in control.", "A new constitution in January 1976 established Democratic Kampuchea as a Communist People's Republic, and a 250-member Assembly of the Representatives of the People of Kampuchea (PRA) was selected in March to choose the collective leadership of a State Presidium, the chairman of which became the head of state.Prince Sihanouk resigned as head of state on 2 April.", "On 14 April, after its first session, the PRA announced that Khieu Samphan would chair the State Presidium for a 5-year term.", "It also picked a 15-member cabinet headed by Pol Pot as prime minister.", "Prince Sihanouk was put under virtual house arrest.Democratic Kampuchea's relations with Vietnam and Thailand worsened rapidly as a result of border clashes and ideological differences.", "While communist, the CPK was fiercely nationalistic, and most of its members who had lived in Vietnam were purged.", "Democratic Kampuchea established close ties with the People's Republic of China, and the Cambodian-Vietnamese conflict became part of the Sino-Soviet rivalry, with Moscow backing Vietnam.", "Border clashes worsened when the Democratic Kampuchea military attacked villages in Vietnam.", "The regime broke off relations with Hanoi in December 1977, protesting Vietnam's alleged attempt to create an Indochina Federation.", "In mid-1978, Vietnamese forces invaded Cambodia, advancing about before the arrival of the rainy season.The reasons for Chinese support of the CPK was to prevent a pan-Indochina movement, and maintain Chinese military superiority in the region.", "The Soviet Union supported a strong Vietnam to maintain a second front against China in case of hostilities and to prevent further Chinese expansion.", "Since Stalin's death, relations between Mao-controlled China and the Soviet Union had been lukewarm at best.", "In February to March 1979, China and Vietnam would fight the brief Sino-Vietnamese War over the issue.In December 1978, Vietnam announced the formation of the Kampuchean United Front for National Salvation (KUFNS) under Heng Samrin, a former DK division commander.", "It was composed of Khmer Communists who had remained in Vietnam after 1975 and officials from the eastern sector—like Heng Samrin and Hun Sen—who had fled to Vietnam from Cambodia in 1978.In late December 1978, Vietnamese forces launched a full invasion of Cambodia, capturing Phnom Penh on 7 January 1979 and driving the remnants of Democratic Kampuchea's army westward toward Thailand.===Destruction and deaths caused by the regime===Choeung Ek Monument contains more than 5,000 human skulls.20,000 people died of exhaustion or disease during the evacuation of Phnom Penh and its aftermath.", "Many of those forced to evacuate the cities were resettled in newly created villages, which lacked food, agricultural implements, and medical care.", "Many who lived in cities had lost the skills necessary for survival in an agrarian environment.", "Thousands starved before the first harvest.", "Hunger and malnutrition—bordering on starvation—were constant during those years.", "Most military and civilian leaders of the former regime who failed to disguise their pasts were executed.Some of the ethnicities in Cambodia, such as the Cham and Vietnamese, suffered specific and targeted and violent persecutions, to the point of some international sources referring to it as the \"Cham genocide\".", "Entire families and towns were targeted and attacked with the goal of significantly diminishing their numbers and eventually eliminated them.", "Life in 'Democratic Kampuchea' was strict and brutal.", "In many areas of the country people were rounded up and executed for speaking a foreign language, wearing glasses, scavenging for food, absent for government assigned work, and even crying for dead loved ones.", "Former businessmen and bureaucrats were hunted down and killed along with their entire families; the Khmer Rouge feared that they held beliefs that could lead them to oppose their regime.", "A few Khmer Rouge loyalists were even killed for failing to find enough 'counter-revolutionaries' to execute.Rooms of the Tuol Sleng Genocide Museum contain thousands of photos taken by the Khmer Rouge of their victims.When Cambodian socialists began to rebel in the eastern zone of Cambodia, Pol Pot ordered his armies to exterminate 1.5 million eastern Cambodians which he branded as \"Cambodians with Vietnamese minds\" in the area.", "The purge was done speedily and efficiently as Pol Pot's soldiers quickly killed at least more than 100,000 to 250,000 eastern Cambodians right after deporting them to execution site locations in Central, North and North-Western Zones within a month's time, making it the bloodiest episode of mass murder under Pol Pot's regime.Religious institutions were not spared by the Khmer Rouge as well, in fact religion was so viciously persecuted to such an extent that the vast majority of Cambodia's historic architecture, 95% of Cambodia's Buddhist temples, was completely destroyed.Ben Kiernan estimates that 1.671 million to 1.871 million Cambodians died as a result of Khmer Rouge policy, or between 21% and 24% of Cambodia's 1975 population.", "A study by French demographer Marek Sliwinski calculated slightly fewer than 2 million unnatural deaths under the Khmer Rouge out of a 1975 Cambodian population of 7.8 million; 33.5% of Cambodian men died under the Khmer Rouge compared to 15.7% of Cambodian women.", "According to a 2001 academic source, the most widely accepted estimates of excess deaths under the Khmer Rouge range from 1.5 million to 2 million, although figures as low as 1 million and as high as 3 million have been cited; conventionally accepted estimates of deaths due to Khmer Rouge executions range from 500,000 to 1 million, \"a third to one half of excess mortality during the period.\"", "However, a 2013 academic source (citing research from 2009) indicates that execution may have accounted for as much as 60% of the total, with 23,745 mass graves containing approximately 1.3 million suspected victims of execution.", "While considerably higher than earlier and more widely accepted estimates of Khmer Rouge executions, the Documentation Center of Cambodia (DC-Cam)'s Craig Etcheson defended such estimates of over one million executions as \"plausible, given the nature of the mass grave and DC-Cam's methods, which are more likely to produce an under-count of bodies rather than an over-estimate.\"", "Demographer Patrick Heuveline estimated that between 1.17 million and 3.42 million Cambodians died unnatural deaths between 1970 and 1979, with between 150,000 and 300,000 of those deaths occurring during the civil war.", "Heuveline's central estimate is 2.52 million excess deaths, of which 1.4 million were the direct result of violence.", "Despite being based on a house-to-house survey of Cambodians, the estimate of 3.3 million deaths promulgated by the Khmer Rouge's successor regime, the People's Republic of Kampuchea (PRK), is generally considered to be an exaggeration; among other methodological errors, the PRK authorities added the estimated number of victims that had been found in the partially-exhumed mass graves to the raw survey results, meaning that some victims would have been double-counted.An estimated 300,000 Cambodians starved to death between 1979 and 1980, largely as a result of the after-effects of Khmer Rouge policies." ], [ "Vietnamese occupation and the PRK (1979–93)", "Salvation Front at the former head office in Phnom PenhOn 10 January 1979, after the Vietnamese army and the KUFNS (Kampuchean United Front for National Salvation) invaded Cambodia and overthrew the Khmer Rouge, the new People's Republic of Kampuchea (PRK) was established with Heng Samrin as head of state.", "Pol Pot's Khmer Rouge forces retreated rapidly to the jungles near the Thai border.", "The Khmer Rouge and the PRK began a costly struggle that played into the hands of the larger powers China, the United States and the Soviet Union.", "The Khmer People's Revolutionary Party's rule gave rise to a guerrilla movement of three major resistance groups – the FUNCINPEC (Front Uni National pour un Cambodge Indépendant, Neutre, Pacifique, et Coopératif), the KPLNF (Khmer People's National Liberation Front) and the PDK (Party of Democratic Kampuchea, the Khmer Rouge under the nominal presidency of Khieu Samphan).", "\"All held dissenting perceptions concerning the purposes and modalities of Cambodia's future\".", "Civil war displaced 600,000 Cambodians, who fled to refugee camps along the border to Thailand and tens of thousands of people were murdered throughout the country.Peace efforts began in Paris in 1989 under the State of Cambodia, culminating two years later in October 1991 in a comprehensive peace settlement.", "The United Nations was given a mandate to enforce a ceasefire and deal with refugees and disarmament known as the United Nations Transitional Authority in Cambodia (UNTAC)." ], [ "Modern Cambodia (1993–present)", "King Norodom SihamoniOn 23 October 1991, the Paris Conference reconvened to sign a comprehensive settlement giving the UN full authority to supervise a cease-fire, repatriate the displaced Khmer along the border with Thailand, disarm and demobilise the factional armies, and prepare the country for free and fair elections.", "Prince Sihanouk, President of the Supreme National Council of Cambodia (SNC), and other members of the SNC returned to Phnom Penh in November 1991, to begin the resettlement process in Cambodia.", "The UN Advance Mission for Cambodia (UNAMIC) was deployed at the same time to maintain liaison among the factions and begin demining operations to expedite the repatriation of approximately 370,000 Cambodians from Thailand.On 16 March 1992, the UN Transitional Authority in Cambodia (UNTAC) arrived in Cambodia to begin implementation of the UN settlement plan and to become operational on 15 March 1992 under Yasushi Akashi, the Special Representative of the U.N. Secretary General.", "UNTAC grew into a 22,000-strong civilian and military peacekeeping force tasked to ensure the conduct of free and fair elections for a constituent assembly.Win-Win Memorial, dedicated to the ending of the Cambodian Civil War in 1998Over 4 million Cambodians (about 90% of eligible voters) participated in the May 1993 elections.", "Pre-election violence and intimidation was widespread, caused by SOC (State of Cambodia – made up largely of former PDK cadre) security forces, mostly against the FUNCINPEC and BLDP parties according to UNTAC.", "The Khmer Rouge or Party of Democratic Kampuchea (PDK), whose forces were never actually disarmed or demobilized blocked local access to polling places.", "Prince Ranariddh's (son of Norodom Sihanouk) royalist Funcinpec Party was the top vote recipient with 45.5% of the vote, followed by Hun Sen's Cambodian People's Party and the Buddhist Liberal Democratic Party, respectively.", "Funcinpec then entered into a coalition with the other parties that had participated in the election.", "A coalition government resulted between the Cambodian People's Party and FUNCINPEC, with two co-prime ministers – Hun Sen, since 1985 the prime minister in the Communist government, and Norodom Ranariddh.The parties represented in the 120-member assembly proceeded to draft and approve a new constitution, which was promulgated 24 September 1993.It established a multiparty liberal democracy in the framework of a constitutional monarchy, with the former Prince Sihanouk elevated to King.", "Prince Ranariddh and Hun Sen became First and Second Prime Ministers, respectively, in the Royal Cambodian Government (RGC).", "The constitution provides for a wide range of internationally recognised human rights.Hun Sen and his government have seen much controversy.", "Hun Sen was a former Khmer Rouge commander who was originally installed by the Vietnamese and, after the Vietnamese left the country, maintains his strong man position by violence and oppression when deemed necessary.", "In 1997, fearing the growing power of his co-Prime Minister, Prince Norodom Ranariddh, Hun launched a coup, using the army to purge Ranariddh and his supporters.", "Ranariddh was ousted and fled to Paris while other opponents of Hun Sen were arrested, tortured and some summarily executed.On 4 October 2004, the Cambodian National Assembly ratified an agreement with the United Nations on the establishment of a tribunal to try senior leaders responsible for the atrocities committed by the Khmer Rouge.", "International donor countries have pledged a US$43 Million share of the three-year tribunal budget as Cambodia contributes US$13.3 Million.", "The tribunal has sentenced several senior Khmer Rouge leaders since 2008.Cambodia is still infested with countless land mines, indiscriminately planted by all warring parties during the decades of war and upheaval.The Cambodia National Rescue Party was dissolved ahead of the 2018 Cambodian general election and the ruling Cambodian People's Party also enacted tighter curbs on mass media.", "The CPP won every seat in the National Assembly without a major opposition, effectively solidifying ''de facto'' one-party rule in the country.Cambodia’s longtime Prime Minister Hun Sen, one of the world’s longest-serving leaders, has a very firm grip on power.", "He has been accused of the crackdown on opponents and critics.", "His Cambodian People’s Party (CPP) has been in power since 1979.In December 2021, Prime Minister Hun Sen announced his support for his son Hun Manet to succeed him after the next election, which is expected to take place in 2023.In July 2023 election, the ruling Cambodian People’s Party (CPP) easily won by landslide in flawed election, after disqualification of Cambodia’s most important opposition, Candlelight Party.", "On 22 August 2023, Hun Manet was sworn in as the new Cambodian prime minister." ], [ "See also" ], [ "References", "'''Attribution:'''* – ===Works cited===*" ], [ "Further reading", "* Chanda, Nayan.", "\"China and Cambodia: In the mirror of history.\"", "''Asia Pacific Review'' 9.2 (2002): 1-11.", "* Chandler, David.", "''A history of Cambodia'' (4th ed.", "2009) online.", "* Corfield, Justin.", "''The history of Cambodia'' (ABC-CLIO, 2009).", "* Herz, Martin F. ''Short History of Cambodia'' (1958) online* Slocomb, Margaret.", "''An economic history of Cambodia in the twentieth century'' (National University of Singapore Press, 2010).", "* Strangio, Sebastian.", "''Cambodia: From Pol Pot to Hun Sen and Beyond'' (2020)" ], [ "External links", "* Records of the United Nations Advance Mission in Cambodia (UNAMIC) (1991-1992) at the United Nations Archives* Constitution of Cambodia* State Department Background Note: Cambodia* Summary of UNTAC mission* History of Cambodian Civil War from the Dean Peter Krogh Foreign Affairs Digital Archives* Cambodia under Sihanouk, 1954–70* Selective Mortality During the Khmer Rouge Period in Cambodia* Crossroads in Cambodia: The United Nation's responsibility to withdrawn involvement from the establishment of a Cambodian Tribunal to prosecute the Khmer Rouge* BBC article* David Chandler - A History Of Cambodia, 4th Edition Westview Press ( 2009)" ] ]

[ [ "Geography of Cambodia" ], [ "Introduction", "Cambodia is a country in mainland Southeast Asia.", "It borders Thailand, Laos, Vietnam, the Gulf of Thailand and covers a total area of approximately .", "The country is situated in its entirety inside the tropical Indomalayan realm and the Indochina Time zone (ICT).Cambodia's main geographical features are the low lying Central Plain that includes the Tonlé Sap basin, the lower Mekong River flood-plains and the Bassac River plain surrounded by mountain ranges to the north, east, in the south-west and south.", "The central lowlands extend into Vietnam to the south-east.", "The south and south-west of the country constitute a long coast at the Gulf of Thailand, characterized by sizable mangrove marshes, peninsulas, sandy beaches and headlands and bays.", "Cambodia's territorial waters account for over 50 islands.", "The highest peak is Phnom Aural, sitting above sea level.The landmass is bisected by the Mekong River, which at is the longest river in Cambodia.", "After extensive rapids, turbulent sections and cataracts in Laos, the river enters the country at Stung Treng province, is predominantly calm and navigable during the entire year as it widens considerably in the lowlands.", "The Mekong's waters disperse into the surrounding wetlands of central Cambodia and strongly affect the seasonal nature of the Tonlé Sap lake.Two third of the country's population live in the lowlands, where the rich sediment deposited during the Mekong's annual flooding makes the agricultural lands highly fertile.", "As deforestation and over-exploitation affected Cambodia only in recent decades, forests, low mountain ranges and local eco-regions still retain much of their natural potential and although still home to the largest areas of contiguous and intact forests in mainland Southeast Asia, multiple serious environmental issues persist and accumulate, which are closely related to rapid population growth, uncontrolled globalization and inconsequential administration.The majority of the country lies within the Tropical savanna climate zone, as the coastal areas in the South and West receive noticeably more and steady rain before and during the wet season.", "These areas constitute the easternmost fringes of the south-west monsoon, determined to be inside the Tropical monsoon climate.", "Countrywide there are two seasons of relatively equal length, defined by varying precipitation as temperatures and humidity are generally high and steady throughout the entire year." ], [ "Geological development", "alt=Mainland Southeast Asia consists of allochthonous continental blocks from Gondwanaland.", "These include the South China, Indochina, Sibumasu, and West Burma blocks, which amalgamated to form the Southeast Asian continent during the Paleozoic and Mesozoic periods.The current geological structure of South China and South-East Asia is determined to be the response to the \"Indo-sinian\" collision in South-East Asia during the Carboniferous.", "The Indo-Sinian orogeny was followed by extension of the Indo-Chinese block, the formation of rift basins and thermal subsidence during the early Triassic.The Indochina continental block, which is separated from the South China Block by the Jinshajiang-Ailaoshan Suture zone, is an amalgamation of the Viet-Lao, Khorat-Kontum, Uttaradit (UTD), and Chiang Mai-West Kachin terranes, all of which are separated by suture zones or ductile shear zones.The Khorat-Kontum terrane, which includes western Laos, Cambodia and southern Vietnam, consists of the Kontum metamorphic complex, Paleozoic shallow marine deposits, upper Permian arc volcanic rocks and Mesozoic terrigenous sedimentary rocks.The central plains consist mainly of Quaternary sands, loam and clay, as most of the northern mountain regions and the coastal region are largely composed of Cretaceous granite, Triassic stones and Jurassic sandstone formations." ], [ "General topography", "Geographic map of CambodiaCultivated lowlands in rural Takéo Province at the end of the dry season, May 2010Borassus flabellifer - sugar palmBowl- or saucer-shaped, Cambodia covers in the south-western part of the Indochinese peninsula as its landmass and marine territory is situated entirely within the tropics.The bowl's bottom represents Cambodia's interior, about 75 percent, consisting of alluvial flood-plains of the Tonlé Sap basin, the lower Mekong River and the Bassac River plain, whose waters feed the large and almost centrally located wetlands.", "As humans preferably settle in these fertile and easily accessible central lowlands, major transformations and widespread cultivation through wet-rice agriculture have over the centuries shaped the landscape into distinctive regional cultivated lands.Domestic plants, such as sugar palms, Coconut trees and banana groves almost exclusively skirt extensive rice paddies, as natural vegetation is confined to elevated lands and near waterways.", "The Mekong traverses the north to south-east portions of the country, where the low-lying plains extend into Vietnam and reach the South China Sea at the Mekong Delta region.Cambodia's low mountain ranges - representing the walls of the bowl - remain as the result of only rather recent substantial infrastructural development and economic exploitation - in particular in remote areas - formidably forested.", "The country is fringed to the north by the Dangrek Mountains plateau, bordering Thailand and Laos, to the north-east by the Annamite Range, in the south-west by the Cardamom Mountains and in the South by the Elephant Mountains.", "Highlands to the north-east and to the east merge into the Central Highlands and the Mekong Delta lowlands of Vietnam.A heavily indented coastline at the Gulf of Thailand of length and 60 offshore islands, that dot the territorial waters and locally merge with tidal mangrove marshes - the environmental basis for a remarkable range of marine and coastal eco-regions.===Soils===Low fertile Acrisol\"Sandy materials cover a large proportion of the landscape of Cambodia, on account of the siliceous sedimentary formations that underlie much of the Kingdom.", "Mesozoic sandstone dominates most of the basement geology in Cambodia and hence has a dominating influence on the properties of upland soils.", "Arenosols (sandy soils featuring very weak or no soil development) are mapped on only 1.6% of the land area.", "\"\"Sandy surface textures are more prevalent than the deep sandy soils that fit the definition for Arenosols.", "Sandy textured profiles are common amongst the most prevalent soil groups, including Acrisols and Leptosols.", "The Acrisols are the most prevalent soil group occupying the lowlands - nearly half of the land area of Cambodia.", "Low fertility and toxic amounts of aluminium pose limitations to its agricultural use, crops that can be successfully cultivated include rubber tree, oil palm, coffee and sugar cane.The main subgroups are: Gleyic Acrisols (20.5%, Haplic Acrisols (13.3%), Plinthic Acrisol (8.7%) and Ferric Acrisol (6.3%).", "\"===Geographical extremes===* '''Northernmost point''': Ta Veaeng District, Rattanakiri Province ()* '''Southernmost point''': Koh Poulo Wai, Kampot Province ()* '''Easternmost point''': Ou Ya Dav District, Rattanakiri Province ()* '''Westernmost point''': Malai District, Banteay Meanchey Province ()" ], [ "Regions", "===Central plain===Extensive flooding in central CambodiaThe vast alluvial and lacustrine interconnected Cambodian flood-plain is a geologically relatively recent depression where the sediments of the Mekong and its tributaries accumulate as waters are subject to frequent course changes.", "The area covers .", "The Tonlé Sap lake and - river system occupies the lowest area.", "The Tonle Sap river is a waterway that branches off the Mekong near Phnom Penh in the north-westerly direction and meets the Tonle Sap lake after around .", "Its waters' flow reverses direction every year, caused by greatly varying amounts of water carried by the Mekong over the course of a year and the impact of monsoonal rains, that coincides with the river's maximum.The plains of the Mekong and Tonle Sap basin are confined in the North by the Dangrek and Central Annamite Mountains, and to the South by the Cardamom Mountains and Elephant Mountains.", "The plains completely surround the Tonle Sap Lake in the western half of the country and wind their way through the middle of the country following the course of the Mekong River.", "The two basins actually form a single body of water, the whole of which effects about 75% of Cambodia’s land cover.===Flow reversal===The volume of alt=The Mekong river and its tributaries increase water volumes in spring (May) on the northern hemisphere, mainly caused by melting snows.", "As the Mekong enters Cambodia (over 95% of its waters have already joined the river) it widens and inundates large areas.The plain's deepest point - the Tonle Sap - flooded area varies from a low of around with a depth of around 1 meter at the end of the dry season (April) to and a depth of up to 9 meters in October/November.", "This figure rose to during 2000 when some of the worst flood conditions recorded caused over 800 deaths in Cambodia and Vietnam.Inflow starts in May/June with maximum rates of flow of around 10,000 m3/s by late August and ends in October/November, amplified by precipitation of the annual monsoon.", "In November the lake reaches its maximum size.", "The annual monsoon coincides to cease around this time of the year.", "As the Mekong river begins its minimum around this time of the year and its water level falls deeper than the inundated Tonle Sap lake, Tonle Sap river and surrounding wetlands, waters of the lake's basin now drains via the Tonle Sap river into the Mekong.As a result the Tonle Sap River (length around ) flows 6 months a year from South-East (Mekong) to North-West (lake) and 6 month a year in the opposite direction.", "The mean annual reverse flow volume in the Tonle Sap is , or about half of the maximum lake volume.", "A further 10% is estimated to enter the system by overland flow from the Mekong.", "The Mekong branches off into several arms near Phnom Penh and reaches Vietnamese territory south of Koh Thom and Loek Daek districts of Kandal Province.===Southern Mountains===Tatai River, draining the southern slopes of the Cardamom MountainsKampot Province, countryside with remote Elephant MountainsThis region represents the eastern parts of the original extent of the wet evergreen forests that cover the Cardamom - and Elephant Mountains in South-West Cambodia and along the mountains east of Bangkok in Thailand.The densely wooded hills receive rainfall of annually on their western slopes (which are subject to the South-West monsoons) but only on their eastern - rain shadow - slopes.", "'''The Cardamom/Krâvanh Mountains'''Occupying Koh Kong Province and Kampong Speu Province, running in a north-western to south-eastern direction and rising to more than .", "The highest mountain of Cambodia, Phnom Aural, at is located in Aoral District in Kampong Speu Province.The Cardamom Mountains form - including the north-western part of Chanthaburi Province, Thailand, the 'Soi Dao Mountains' - ''the Cardamom Mountains Moist Forests Ecoregion'', that is considered to be one of the most species-rich and intact natural habitats in the region.", "The climate, size inaccessibility and seclusion of the mountains have allowed a rich variety of wildlife to thrive.", "The Cardamom and Elephant Mountains remain to be fully researched and documented.", "'''The Elephant Mountains'''Chuŏr Phnum Dâmrei - A north-south-trending range of high hills, an extension of the Cardamom/Krâvanh Mountains, in south-eastern Cambodia, rising to elevations of between 500 and 1,000 meters.", "Extending north from the Gulf of Thailand, they reach a high point in the Bok Koŭ ridge at Mount Bokor near the sea.To the south-west of the Southern mountain ranges extends a narrow coastal plain that contains the Kampong Saom Bay area and the Sihanoukville peninsula, facing the Gulf of Thailand.===Northern Mountains==='''The Dangrek Mountains'''A forested range of hills averaging , dividing Thailand from Cambodia, mainly formed of massive sandstone with slate and silt.", "A few characteristic basalt hills are located on the northern side of the mountain chain.", "This east–west-trending range extends from the Mekong River westward for approximately , merging with the highland area near San Kamphaeng, Thailand.", "Essentially the southern escarpment of the sandstone Khorat Plateau of northeastern Thailand, the Dângrêk range slopes gradually northward to the Mun River in Thailand but falls more abruptly in the south to the Cambodian plain.", "Its highest point is .The watershed along the escarpment in general terms marks the boundary between Thailand and Cambodia, however there are exceptions.", "The region is covered in dry evergreen forest, mixed dipterocarp forest, and deciduous dipterocarp forests.", "Tree species like Pterocarpus macrocarpus, Shorea siamensis and Xylia xylocarpa var.", "kerrii dominate.", "Illegal logging are issues on both, the Thai as well as on the Cambodian side, leaving large hill stretches denuded, vulnerable tree species such as Dalbergia cochinchinensis have been affected.", "Forest fires are common during the dry season.Chrey Thom Waterfall Mondulkiri Province'''Annamite Range'''Lying to the east of the Mekong River, the long chain of mountains called the Annamite Mountains of Indochina and the lowlands that surround them make up the Greater Annamites ecoregion.", "Levels of rainfall vary from annually.", "Mean annual temperatures are about .", "This eco-region contains some of the last relatively intact moist forests in Indochina.", "Moisture-laden monsoon winds, that blow in from the Gulf of Tonkin ensure permanent high air humidity.", "Plants and animals adapted to moist conditions, to seek refuge here and evolve into highly specialized types that are found nowhere else on Earth.", "'''Ethnically diverse'''More than 30 ethnic groups of indigenous people live in the Annamites, each with their distinctive and traditional music, language, dress and customs.", "The natural resources of the Greater Annamites are vital to all of these people.===Eastern Highlands===Mountain panorama view in Mondulkiri Province, north-eastern Cambodia, November 2012Tall grasses and deciduous forests cover the ground east of the Mekong River in Mondulkiri, where the transitional plains merge with the eastern highlands at altitudes from .", "The landscape has suffered from rubber farming, logging and particularly mining, although sizable areas of pristine jungle survive, which are home to rare and endemic wildlife.===Coast===Cambodia's coastal area covers , distributed among four provinces: Sihanoukville province, Kampot province, Koh Kong province, and Kep province.", "The total length of the Cambodian coastal area has been disputed.", "The most widely accepted length is , a 1997 survey by the DANIDA organization announced a length at , and in 1973 the ''Oil Authority'' found the coast to be long.", "The Food and Agriculture Organization claims a length of in one of its studies.The southern mountain ranges drain to the south and west towards the shallow sea.", "Sediments on the continental shelf are the basis for extensive mangroves marshes, in particular in the Koh Kong province and the Ream National Park.===Islands===Cambodia’s islands fall under administration of the 4 coastal provinces.", "\"There are 60 islands in Cambodia's coastal waters.", "They include 23 in Koh Kong province, 2 in Kampot province, 22 in Sihanoukville and 13 in Kep city.sic\" Most islands are, apart from the two small groups of the outer islands, in relative proximity to the coast.", "The islands and the coastal region of Koh Kong Province are mainly composed of upper Jurassic and lower Cretaceous sandstone massives.", "The north-westernmost islands near and around the Kaoh Pao river delta (Prek Kaoh Pao) area are to a great extent sediments of estuaries and rivers, very flat and engulfed in contiguous mangrove marshes." ], [ "Climate", "Köppen climate classification zonesDANIDAWorldwide zones of Tropical savanna climate (Aw).Worldwide zones of tropical monsoon climate (Am).Cambodia's climate, like that of much of the rest of mainland Southeast Asia is dominated by monsoons, which are known as tropical wet and dry because of the distinctly marked seasonal differences.", "The monsoonal air-flows are caused by annual alternating high pressure and low pressure over the Central Asian landmass.", "In summer, moisture-laden air—the southwest monsoon—is drawn landward from the Indian Ocean.The flow is reversed during the winter, and the northeast monsoon sends back dry air.", "The southwest monsoon brings the rainy season from mid-May to mid-September or to early October, and the northeast monsoon flow of drier and cooler air lasts from early November to March.", "Temperatures are fairly uniform throughout the Tonlé Sap Basin area, with only small variations from the average annual mean of around .The maximum mean is about ; the minimum mean, about .", "Maximum temperatures of higher than , however, are common and, just before the start of the rainy season, they may rise to more than .", "Minimum night temperatures sporadically fall below .", "in January, the coldest month.", "May is the warmest month - although strongly influenced by the beginning of the wet season, as the area constitutes the easternmost fringe of the south-west monsoon.", "Tropical cyclones only rarely cause damage in Cambodia.The total annual rainfall average is between , and the heaviest amounts fall in the southeast.", "Rainfall from April to September in the Tonlé Sap Basin-Mekong Lowlands area averages annually, but the amount varies considerably from year to year.", "Rainfall around the basin increases with elevation.", "It is heaviest in the mountains along the coast in the southwest, which receive from to more than of precipitation annually as the southwest monsoon reaches the coast.This area of greatest rainfall drains mostly to the sea; only a small quantity goes into the rivers flowing into the basin.", "Relative humidity is high throughout the entire year; usually exceeding 90%.", "During the dry season daytime humidity rates average around 50 percent or slightly lower, climbing to about 90% during the rainy season." ], [ "Hydrology", "'''Floating homes on the Mekong'''An overview of drainage dividesMekong tributary, Stung Treng ProvinceThe Mekong River and its tributaries comprise one of the largest river systemsin the world.", "The central Tonle Sap, the ''Great Lake'' has several input rivers, the most important being the Tonle Sap River, which contributes 62% of the total water supply during the rainy season.", "Direct rainfall on the lake and the other rivers in the sub-basin contribute the remaining 38%.", "Major rivers are the Sen river, Sreng River, Stung Pouthisat River, Sisophon River, Mongkol Borei River, and Sangkae River.Smaller rivers in the southeast, the Cardamom Mountains and Elephant Range form separate drainage divides.", "To the east the rivers flow into the Tonle Sap, as in the south-west rivers flow into the Gulf of Thailand.", "Toward the southern slopes of the Elephant Mountains, small rivers flow south-eastward on the eastern side of the divide.The Mekong River flows southward from the Cambodia-Laos border to a point south of Kratié (town), where it turns west for about and then turns southwest towards Phnom Penh.", "Extensive rapids run north of Kratie city.", "From Kampong Cham Province the gradient slopes very gently, and inundation of areas along the river occurs at flood stage.", "From June through November—through breaks in the natural levees that have built up along its course.", "At Phnom Penh four major water courses meet at a point called the Chattomukh (Four Faces).", "The Mekong River flows in from the northeast and the Tonle Sap river emanates from the Tonle Sap—flows in from the northwest.", "They divide into two parallel channels, the Mekong River proper and the Bassac River, and flow independently through the delta areas of Cambodia and Vietnam to the South China Sea.The flow of water into the Tonle Sap is seasonal.", "In spring, the flow of the Mekong River, fed by monsoon rains, increases to a point where its outlets through the delta can't handle the enormous volume of water.", "At this point, the water pushes northward up the Tonle Sap river and empties into the Tonle Sap lake, thereby increasing the size of the lake from about to about at the height of the flooding.", "After the Mekong's waters crest — when its downstream channels can handle the volume of water — the flow reverses, and water flows out of the engorged lake.As the level of the Tonle Sap retreats, it deposits a new layer of sediment.", "The annual flooding, combined with poor drainage immediately around the lake, transforms the surrounding area into marshlands, unusable for agricultural purposes during the dry season.", "The sediment deposited into the lake during the Mekong's flood stage appears to be greater than the quantity carried away later by the Tonle Sap River.", "Gradual silting of the lake would seem to be occurring; during low-water level, it is only about deep, while at flood stage it is between deep." ], [ "Vegetation & ecoregions", "A map of forests, vegetation and land use in CambodiaCambodia has one of the highest levels of forest cover in the region as the interdependence of Cambodia’s geography and hydrology makes it rich in natural resources and biological diversity - among the bio-richest countries in Southeast Asia.", "The Royal Government of Cambodia estimates Cambodia contains approximately 10.36 million hectares of forest cover, representing approximately 57.07% of Cambodia’s land area (2011).", "On the contrary, international observers and independent sources provide rather different numbers.", "Consensus permeates, as most sources agree, that deforestation in Cambodia, loss of seasonal wetlands and habitat destruction - among countless minor factors - correlates with the absence of strict administrative control and indifference in law enforcement - not only in Cambodia but the entire region.Figures and assessments are numerous as are available sources.", "as seen in numbers below, which provide a wide range for interpretation.", "About (1%) of forest cover is planted forest.", "Overall Cambodia’s forests contain an estimated 464 million metric tonnes of carbon stock in living forest biomass.", "Approximately 40% of Cambodia’s Forests have some level of protection, while one of the Cambodia Millennium Development Goals targets is to achieve a 60% forest cover by 2015.Cambodia Forest Cover, 2002 Forest Types Area (ha) PercentageEvergreen Forest 3,720,506 20.49 Semi-evergreen forest 1,455,190 8.01 Deciduous forest 4,833,861 26.62 Other forest 1,094,726 6.03 Non-forest 7,056,388 38.85 Source: United NationsCambodia Forest Cover, 2002 Forest Types Area (ha) Percentageforests - commercially unattractive 3.200.000 30 forests - commercially attractive 630.000 6 flooded forest - cut and/or converted 30 flooded forest - healthy 450.000 lost area 550.000 55 Source: CAMBODIA DEVELOPMENT RESOURCE INSTITUTEAccording to the ''Forestry Administration'' statistics, a total of 380,000 hectares of forest were cleared between 2002 and 2005/2006 - a deforestation rate of 0.5% per year.", "The main cause of deforestation has been determined to be large-scale agricultural expansions.===Southern Annamites Montane Rain Forests ecoregion===The Southern Annamites Montane Rain Forests ecoregion of the montane forests of Kontuey Nea, \"the dragon's tail\" in the remote north-west of Cambodia, where the boundaries of Cambodia, Laos, and Vietnam meet this is in the northeast, not the northwest?, is remarkably rich in biodiversity.", "The relatively intact forests occupy a broad topographic range - from lowlands with wet evergreen forests to montane habitats with evergreen hardwood and conifer forests.", "The complex geological, topographic and climatic ( rainfall and temperature ) facets that characterize the region make forest structure and composition unique and very variable.", "There is an unusually high number of near-endemic and endemic species among the many species to be found in the area.", "The entire eco-region has a size of .", "Southern Annamites montane rain forests: ecoregion territory (in purple)===The Great Lake ecosystem===DipterocarpaceaeThe Tonle Sap, also known as the Great Lake in central Cambodia is the largest freshwater lake in Southeast Asia and one of the richest inland fishing grounds in the world.", "The Lake functions as a natural flood water reservoir for the Mekong system as a whole and therefore is an important source of water for the Mekong Delta during the dry season.", "The ecosystem has developed as a result of the Mekong’s seasonal flow fluctuations.A belt of freshwater mangroves known as the \"flooded forest\" surrounds the lake.", "The floodplains in turn are surrounded by low hills, covered with evergreen seasonal tropical forest with substantial dipterocarp vegetation or deciduous dry forest.", "The eco-region consists of a mosaic of habitats for a great number of species.", "The forest gradually yields to bushes and finally grassland with increasing distance from the lake.Henri Mouhot: \"Travels in the Central Parts of Indo-China\" 1864On higher quality soils or at higher elevation, areas of mixed deciduous forest and semi-evergreen forests occur.", "This variety of vegetation types accounts for the quantity and diversity of species of the Great Lake ecosystem.", "Interlocking forest, - grassland and marshland patches provide the many facets and refugia for the abundant local wildlife.The lake’s flooded forest and the surrounding floodplains are of utmost importance for Cambodia's agriculture as the region represents the cultural heart of Cambodia, the center of the national freshwater fishery industry - the nation's primary protein source.Threats to the lake include widespread pollution, stress through growth of the local population which is dependent on the lake for subsistence and livelihood, over-harvesting of fish and other aquatic - often endangered - species, habitat destruction and potential changes in the hydrology, such as the construction and operation of dams, that disrupt the lake's natural flood cycle.", "However, concerns that the lake is rapidly filling with sediment seem - according to studies - to be unfounded at the present time.===Wetlands===Coastal wetlands near Ream, Sihanoukville ProvinceWetlands cover more than 30% of Cambodia.", "In addition to the Mekong River and the Tonle Sap floodplain there are the Stung Sen River and the coastal Stung Koh Pao - and Stung Kep estuaries of Koh Kong Province and Kep Province.", "The freshwater wetlands of Cambodia represent one of the most diverse ecosystems worldwide.", "The area’s extensive wetland habitats are the product of the annual Mekong maximum, the simultaneous wet season and the drainage paths of a number of minor rivers.", "See also:Geography of Cambodia#Hydrology The numerous and varied wetlands are Cambodia's central and traditional settlement area, the productive environments for rice cultivation, freshwater fisheries, other forms of agriculture and aquaculture and the constantly growing tourism sector.", "Considering the eco-region's importance, a variety of plans for local wetland management consolidation exist with varying degrees of completion.===Coastal habitats===Mangrove forests in Koh Kong Province Cambodia, September 2013The Cambodian coastline consists of of over 30 species of mangroves - among the most biologically diverse wetlands on earth.", "The most pristine mangrove forests are found in Koh Kong Province.", "In addition to mangroves, sea-grass beds extend throughout the coastal areas, especially in Kampot Province, the Sihanoukville Bay Delta and the Kep municipal waters.", "The meadows are highly productive, but few animals feed directly on the grasses.", "Those that do tend to be vertebrates such as sea turtles, dabbling ducks and geese.", "\"With their roots deep in mud, jagged and gnarled mangrove trees are able to grow in the brackish wetlands between land and sea where other plant life cannot survive.", "The trees offer refuge and nursery grounds for fish, crabs, shrimp, and mollusks.", "They are nesting - and migratory sites for hundreds of bird species.", "They also provide homes for monkeys, lizards, sea turtles, and many other animals as well as countless insects.", "\"\"Until relatively recently, the mangroves of Koh Kong, Cambodia have remained relatively intact.", "This is partly because of the region’s location — it is an isolated, inaccessible place — and because decades of war and conflict perversely protected the forests from over-exploitation.", "Local people, however, tended to use the forest's sustainability, for food, fuel, medicine, building materials, and other basic needs.\"" ], [ "Fauna", " The endangered Agile gibbonCambodia is home to a wide array of wildlife.", "There are 212 mammal species, 536 bird species, 176 reptile species (including 89 subspecies), 850 freshwater fish species (Tonlé Sap Lake area), and 435 marine fish species.Many of the country's species are recognized by the IUCN or World Conservation Union as threatened, endangered, or critically endangered due to deforestation and habitat destruction, poaching, illegal wildlife trade, farming, fishing, and unauthorized forestry concessions.", "Intensive poaching may have already driven Cambodia's national animal, the Kouprey, to extinction.", "Wild tigers, Eld's deer, wild water buffaloes and hog deer are at critically low numbers." ], [ "Protected areas", "\"The 1993 Royal Decree on the Protection of Natural Areas recognized 23 protected areas, which at the time covered more than 18% of the country’s total land area.", "\"* Natural parks (sometimes described as ‘national parks’)* Wildlife reserves* Protected scenic view areas (sometimes described as ‘protected landscapes’)* Multi-purpose areas" ], [ "Political and human geography", "Cambodia borders Vietnam over a length of , Thailand over a length of and Laos over a length of , with in total and an additional of coastline.", "The capital (''reach thani'') and provinces (''khaet'') of Cambodia are first-level administrative divisions.", "Cambodia is divided into 25 provinces including the capital.Municipalities and districts are the second-level administrative divisions of Cambodia.", "The provinces are subdivided into 159 districts and 26 municipalities.", "The districts and municipalities in turn are further divided into communes (''khum'') and quarters (''sangkat'').===Land use===Cambodia, Laos and Vietnam have experienced major changes in land use and land cover over the last two decades.", "The emergence from cold war rivalries and recent major economic reforms result in a shift from subsistence agrarian modes of production to market-based agricultural production and industrialized economies, which are heavily integrated into regional and global trade systems.Land Use in Cambodia - Sources: World Bank, FAO UN1990200020022010 Agricultural land (km2) in Cambodia 44550.0 47700.0 Agricultural land (% of land area) in Cambodia 25.2 27.0 23.0 Arable land (hectares) in Cambodia 3695000.0 3700000.0Arable land (hectares per person) in Cambodia 0.4 0.3Arable land (% of land area) in Cambodia 20.9 21.0Permanent cropland (% of land area) in Cambodia 0.6 0.8Forest area (km2) in Cambodia 129460.0 115460.0 100940.0Forest area (% of land area) in Cambodia 73.3 65.4 54.0 57.2===Regional divisions===Cambodia's boundaries were for the most part based upon those recognized by France and by neighboring countries during the colonial period.", "The boundary with Thailand runs along the watershed of the Dangrek Mountains, although only in its northern sector.", "The border with Laos and the border with Vietnam result from French administrative decisions and do not follow major natural features.", "Border disputes have broken out in the past and do persist between Cambodia and Thailand as well as between Cambodia and Vietnam.Image:Cambodia, administrative divisions - de - colored, 2013.svg|right|550pxpoly 355 962 361 973 371 973 375 962 381 964 376 955 378 931 390 921 397 905 398 898 393 885 420 844 437 832 442 848 436 855 440 868 431 885 444 902 443 930 436 937 431 933 426 934 407 951 410 955 407 966 413 981 408 996 411 1008 416 1009 418 1015 415 1030 404 1037 379 1090 222 1125 178 1097 257 1035 304 1035 320 1012 350 1008 345 1002 349 991 355 988 360 980 Sihanoukvillepoly 471 1081 492 1033 523 1030 528 1070 524 1095 Keppoly 399 1053 422 1024 412 996 413 941 457 926 440 896 472 913 491 922 515 904 526 907 532 926 548 931 548 938 555 968 590 968 609 1006 591 1033 589 1064 554 1070 542 1103 529 1083 537 1017 492 1028 468 1082 Kampotpoly 518 909 550 969 555 975 590 960 593 998 589 1022 590 1049 600 1070 652 1066 665 1025 687 1006 666 957 672 919 666 889 641 870 638 857 595 855 585 929 Takéopoly 606 779 613 845 666 825 645 770 Phnom Penhpoly 611 725 573 831 614 832 595 856 652 860 655 885 675 898 667 932 673 968 707 964 727 868 712 819 680 799 655 809 654 823 647 829 628 834 617 837 608 826 613 814 615 807 612 798 613 782 623 779 641 780 650 791 656 808 686 799 696 766 667 756 671 740 663 727 643 741 622 735 Kandalpoly 684 805 683 763 724 740 760 736 772 757 820 759 837 776 846 796 838 810 821 820 817 846 812 876 811 889 806 918 808 933 806 950 783 954 759 956 749 981 705 961 722 909 737 867 724 829 Prey Vengpoly 870 805 830 807 821 864 816 897 800 930 802 954 852 925 864 974 874 995 886 966 906 986 940 998 940 963 940 949 944 929 925 914 921 914 905 899 884 881 873 869 873 854 Svay Riengpoly 713 751 688 766 672 756 676 735 662 723 639 735 630 741 621 728 625 704 642 687 646 623 714 639 694 604 746 595 762 575 797 575 829 574 834 618 865 645 900 659 924 681 936 696 934 706 970 713 1014 711 1005 725 1008 761 1014 781 1005 793 965 766 927 751 879 782 862 787 827 762 790 753 762 752 741 728 Kampong Champoly 476 695 458 633 513 609 521 547 584 549 625 574 636 607 635 634 632 668 635 699 622 718 609 736 599 746 565 751 547 760 507 749 Kampong Chhnangpoly 366 738 471 680 511 755 565 759 597 736 601 744 576 830 611 838 597 860 583 921 553 920 519 900 497 918 473 926 446 899 435 894 438 853 435 815 410 805 386 781 Kampong Speupoly 355 964 343 946 342 922 328 920 316 902 302 906 286 954 290 969 275 976 269 966 248 964 240 975 263 1018 251 1029 234 1007 207 972 199 955 214 943 211 926 216 918 208 889 201 889 190 881 187 870 184 842 192 838 185 816 174 796 170 785 169 755 155 736 149 720 139 700 139 691 180 691 191 693 216 706 229 707 252 696 265 696 283 668 293 671 300 665 315 670 345 700 354 701 360 710 379 711 394 732 375 733 379 743 375 747 373 760 379 772 379 786 413 811 420 808 429 808 432 813 441 816 437 835 421 842 392 888 394 897 395 903 388 923 377 932 377 955 380 965 373 963 372 974 362 974 360 964 Koh Kongpoly 60 448 86 450 113 418 129 434 135 490 132 523 111 535 83 537 72 533 70 507 77 489 Pailinpoly 189 134 241 173 247 216 273 197 295 239 371 175 532 213 545 185 557 171 560 106 485 90 424 97 389 95 351 81 310 81 241 96 Oddar Meancheypoly 565 106 557 177 533 203 524 255 533 291 543 312 587 321 576 355 581 395 621 371 641 389 655 428 668 437 761 358 802 327 798 274 776 239 798 231 871 218 852 185 809 167 781 174 747 172 726 151 704 116 697 131 674 147 648 109 635 97 594 89 Preah Vihearpoly 286 212 290 358 171 361 125 346 123 321 29 324 33 301 90 298 93 273 138 248 163 183 186 142 219 177 239 177 242 217 275 201 Banteay Meancheypoly 285 352 280 229 377 183 417 200 493 206 529 209 518 245 524 271 525 287 527 314 587 312 566 382 539 401 536 442 483 502 439 472 402 433 372 389 Siem Reappoly 35 321 115 326 121 354 171 355 239 356 296 363 363 369 408 430 369 453 347 489 341 540 336 573 282 559 243 558 205 565 179 574 164 593 146 595 82 536 149 515 129 418 100 417 92 438 89 446 67 440 46 430 30 407 Battambangpoly 127 594 127 696 214 707 279 685 304 669 379 711 401 733 482 681 454 633 514 610 518 566 474 519 440 471 391 420 363 467 344 498 341 552 339 581 296 561 277 551 260 564 212 560 199 564 189 581 Pursatpoly 466 510 528 566 537 549 561 544 603 557 627 571 635 590 641 609 641 621 640 631 708 647 693 591 748 610 753 568 841 571 792 335 648 440 633 404 643 367 564 380 543 408 533 452 Kampong Thompoly 810 390 846 635 928 696 980 722 1084 709 1086 635 1006 592 982 545 1052 492 1041 427 998 414 968 359 961 337 898 400 870 426 836 403 Kratiepoly 781 230 794 297 795 364 803 412 863 420 926 367 1002 364 1037 367 1048 361 1028 294 1054 249 1046 202 1085 190 1069 93 1022 62 975 83 909 116 939 171 943 211 922 228 859 214 Stung Trenpoly 1071 98 1077 187 1042 209 1050 256 1028 315 1044 359 1055 389 1132 416 1161 404 1163 369 1288 374 1254 254 1226 202 1220 178 1227 119 1246 89 1261 34 1239 54 1234 69 1222 59 1211 62 1191 82 1176 103 1145 93 1135 110 1108 120 Ratanakkiripoly 981 350 988 397 1010 424 1046 427 1045 493 1007 517 991 566 1006 585 1029 629 1096 640 1090 683 1150 685 1185 618 1232 627 1250 644 1272 594 1280 530 1260 464 1262 417 1276 378 1227 372 1183 365 1156 370 1142 399 1116 412 1074 398 1045 375 1026 352 988 354 Mondulkiridesc top-left Number Province Capital Area (km²) Population 1 Banteay Meanchey Serei Saophoan 6,679678,033 2 Battambang Battambang 11,7021,036,523 3 Kampong Cham Kampong Cham 4,549 1,010,098 4 Kampong Chhnang Kampong Chhnang 5,521472,616 5 Kampong Speu Kampong Speu 7,017718,008 6 Kampong Thom Kampong Thom 13,814908,398 7 Kampot Kampot 4,873585,110 8 Kandal Ta Khmau 3,5681,265,805 9 Kep Kep 33680,208 10 Koh Kong Koh Kong 11,160139,722 11 Kratié Kratié 11,094318,523 12 Mondulkiri Senmonorom 14,28860,811 13 Oddar Meanchey Samraong 6,158185,443 14 Pailin Pailin 80370,482 15 Phnom Penh Phnom Penh 7582,234,566 16 Preah Sihanouk Sihanoukville 2,536.68199,902 17 Preah Vihear Tbeng Meanchey 13,788170,852 18 Pursat Pursat 12,692397,107 19 Prey Veng Prey Veng 4,883947,357 20 Ratanakiri Banlung 10,782217,453 21 Siem Reap Siem Reap 10,2291,000,309 22 Stung Treng Stung Treng 11,092111,734 23 Svay Rieng Svay Rieng 2,966498,785 24 Takéo Doun Kaev 3,563843,931 25 Tboung Khmum Suong 4,928 754,000" ], [ "Area and boundaries", "right'''Area:'''''total:''''land:''''water:'''''Maritime claims:'''''territorial sea:''''contiguous zone:''''exclusive economic zone:''''continental shelf:'''''Elevation extremes:'''''lowest point:''Gulf of Thailand ''highest point:''Phnum Aoral '''Border disputes'''* Cambodian–Thai border dispute* Cambodian–Vietnamese land dispute'''Lakes'''* Tonlé Sap Lake* Yak Loum Crater Lake – Ratanakiri" ], [ "Natural resources", "* Oil and natural gas - In addition to the four parts of mining project, the oilfield, Block A was discovered in 2005 and located offshore in the gulf of Thailand Chevron would operate and hold a 30% interest Block A which cover .", "It is expected to get 30-year-production permit in the second quarter of 2011.In late 1969, the Cambodian government granted a permit to a French company to explore for petroleum in the Gulf of Thailand.", "By 1972 none had been located, and exploration ceased when the Khmer Republic (see Appendix B) fell in 1975.Subsequent oil and gas discoveries in the Gulf of Thailand and in the South China Sea, however, could spark renewed interest in Cambodia's offshore area, especially because the country is on the same continental shelf as its Southeast Asian oil-producing neighbors.", "* Timber** ''Dipterocarpus alatus'' (chheuteal tan) sawnwood, veneer, plywood** ''Anisoptera glabra'' (mersawa, phdiek) sawnwood, veneer, plywood** ''Hopea odorata'' (koki) Sawmilling, construction (bridges, boats)** ''Shorea vulgaris'' (choë(r) chông) sawmilling, construction (housing)** ''Heritiera javanica'' (synonym ''Tarrietia javanica'') sawnwood (decorative, furniture)* Gemstones - Gemstone areas are located in Samlot district of Battambang, Paillin, Ratanakkiri, and Takéo Province* Iron ore - Hermatite (Fe2O3); Magnetite (Fe3O4); Limonite (2Fe2O3, 3H2O) - was found in two areas, one located in Phnom Deck and the others located in Koh Keo of Preah Vihear Province, and Thalaborivath of Stung Treng Province.", "According to General Department of Mineral, the total iron reserves in Phnom Deck area are estimated at 5 to 6 Million tons and other deposits may add 2 to 3 Million tons.", "* Gold - Gold deposit was found in four provinces: Kampong Cham (The Rumchek in Memot area), Kampong Thom (Phnom Chi area), Preah Vihear (Phnom Deck in Roveing district), Ratanakiri (Oyadav district) and Mondulkiri* Bauxite – was found in Battambang Province and Chhlong district in Mondulkiri Province.", "* Antimony (Sb) – found in Sre Peang area, Pursat Province* Chromium (Cr) – found in Sre Peang area, Pursat Province* manganese* phosphates* Hydro-power - Hydroelectric dams: Lower Se San 2 Dam, Stung Treng Dam* Arable land* Marine resources'''Total renewable water resources:'''* (2011)'''Freshwater withdrawal (domestic/industrial/agricultural):'''* Total: /yr (4%/2%/94%)* Per capita: /yr (2006)" ], [ "Environmental issues", "Unauthorized sand mining at the Tatai River in the Koh Kong Conservation Corridor, Cambodia 2012A polluted estuary near Ream commune in Sihanoukville province, Cambodia 2014===Natural hazards===* Monsoonal rains (June to November)* Mekong flooding* Occasional droughts===Human impact==='''Issues'''* Illegal logging activities throughout the country* rubber tree mono-cultures and strip mining for gold in the eastern highlands* gem mining in the western region along the border with Thailand* destruction of mangrove swamps threatens natural fisheries, illegal fishing and over-fishing* large scale sand mining in river beds and estuaries of Koh Kong's mangrove marshes affects tidal balanceA nascent environmental movement has been noticed by NGO's - and it is gaining strength, as the example of local resistance against the building of a Chinese hydro-electric dam in the Areng Valley shows.Cambodia has a bad but improving performance in the global Environmental Performance Index (EPI) with an overall ranking of 146 out of 180 countries in 2016.This is among the worst in the Southeast Asian region, only ahead of Laos and Myanmar.", "The EPI was established in 2001 by the World Economic Forum as a global gauge to measure how well individual countries perform in implementing the United Nations' Sustainable Development Goals.The environmental areas where Cambodia performs worst on the EPI (i.e.", "highest ranking) are air quality (148), water resource management (140) and health impacts of environmental issues (137), with the areas of sanitation, environmental impacts of fisheries and forest management following closely.", "Cambodia has an unusually large expanse of protected areas, both on land and at sea, with the land-based protections covering about 20% of the country.", "This secures Cambodia a better than average ranking of 61 in relation to biodiversity and habitat, despite the fact deforestation, illegal logging, construction and poaching are heavily deteriorating these protections and habitats in reality, partly fueled by the government's placement of economic land concessions and plantations within protected areas.In November 2017, the U.S. cut funds to help clear unexploded ordnance including land mines and chemical weapons in Cambodia which it had dropped during the Vietnam War.", "'''Consequences'''* Flooding* Deforestation* Soil erosion in rural areas* Declining fish stocks* Decreasing access to clean water* Habitat loss and declining biodiversity===International agreements and conventions===Cambodia is party to the following treaties:* Convention on Biological Diversity* Convention on Climate Change* MARPOL 73/78* Tropical Timber 94* Ramsar Convention on WetlandsSigned, but not ratified:* Law of the Sea" ], [ "See also" ], [ "References" ], [ "External links", "===National===* Ministry of Land Management Urban Planning and Construction* Forestry Administration* Law on Forestry* law on land use * Ministry of Water Resources and Meteorology * Tonle Sap Authority* Economic Land Concession* Environmental Law* An Assessment of Cambodia’s Draft Environmental Impact Assessment Law* Climate Change Department===International===* National Library of France* National Aquaculture Legislation* Cambodia Forestry Outlook Study* FAO UN* Mekong River Commission* National Adaptation Programme of Action to Climate Change (NAPA)* World reference base for soil resources" ], [ "Further reading", "* Stories from the Mekong* Cardamoms 'one of the crown jewels...* Kampot's forgotten Karst formations" ] ]

[ [ "Demographics of Cambodia" ], [ "Introduction", "Demographic features of the population of Cambodia include population density, ethnicity, education level, health of the populace, economic status, religious affiliations and other aspects of the population." ], [ "Population", "Population developmentBetween 1874 and 1921, the total population of Cambodia increased from about 946,000 to 2.4 million.", "By 1950, it had increased to between 3,710,107 and 4,073,967, and in 1962 it had reached 5.7 million.", "From the 1960s until 1975, the population of Cambodia increased by about 2.2% yearly, the lowest increase in Southeast Asia.By 1975 when the Khmer Rouge took power, the population was estimated at 7.3 million.", "Of this total an estimated one to two million reportedly died between 1975 and 1978.In 1981, the PRK gave the official population figure as nearly 6.7 million, although approximately 6.3 million to 6.4 million is probably more accurate.The average annual rate of population growth from 1978 to 1985 was 2.3% (see table 2, Appendix A).", "A post-Khmer Rouge baby boom pushed the population above 10 million, although growth has slowed in recent years.In 1959, about 45% of the population was under 15 years of age.", "By 1962, this had increased slightly to 46%.", "In 1962, an estimated 52% of the population was between 15 and 64 years of age, while 2% were older than 65.The percentage of males and females in the three groups was almost the same.===Population and age distribution===Cambodian Population Pyramid-2005Population pyramid, urban-rural, Cambodia, 2019Total population (thousands)Population aged 0–14 (%)Population aged 15–64 (%)Population aged 65+ (%) 1950 4 346 42.2 55.1 2.7 1955 4 840 42.3 55.0 2.7 1960 5 433 42.5 54.8 2.7 1965 6 141 42.8 54.4 2.7 1970 6 938 43.2 54.0 2.8 1975 7 308 42.3 54.9 2.8 1980 6 306 39.0 58.1 2.9 1985 7 920 42.1 55.0 2.9 1990 9 532 43.8 53.4 2.8 1995 11 169 47.5 49.7 2.8 2000 12 447 41.6 55.4 3.0 2005 13 358 36.4 60.3 3.3 2010 14 138 31.9 64.3 3.8 2015 15 521 31.6 64.3 4.1 2020 16 719 30.9 64.2 4.9=== Structure of the population ===Age GroupMaleFemaleTotal% Total 7 320 112 7 642 479 14 962 591 100 0–4 806 531 777 854 1 584 385 10.59 5–9 721 480 693 339 1 414 819 9.46 10–14 768 899 735 963 1 504 862 10.06 15–19 878 612 830 980 1 709 592 11.43 20–24 848 931 800 737 1 649 668 11.03 25–29 678 825 712 044 1 390 869 9.30 30–34 613 674 637 973 1 251 647 8.37 35–39 338 735 363 397 702 132 4.69 40–44 411 072 441 415 852 487 5.70 45–49 344 372 395 214 739 586 4.94 50–54 295 645 352 214 648 347 4.33 55–59 190 528 288 806 479 334 3.20 60–64 153 721 218 867 372 588 2.49 65–69 105 605 147 502 253 107 1.69 70–74 76 017 108 069 184 086 1.23 75–79 47 601 72 558 120 159 0.80 80+ 39 864 65 059 104 923 0.70Age groupMaleFemaleTotalPercent 0–14 2 296 910 2 207 156 4 504 066 30.10 15–64 4 754 115 5 042 135 9 796 250 65.47 65+ 269 087 393 188 662 275 4.43Age GroupMaleFemaleTotal% Total 8 093 453 8 498 636 16 592 089 100 0–4 791 593 755 468 1 547 061 9.32 5–9 792 080 756 481 1 548 561 9.33 10–14 843 604 804 317 1 647 921 9.93 15–19 799 876 773 934 1 573 810 9.49 20–24 647 446 666 588 1 314 034 7.92 25–29 684 545 720 947 1 405 492 8.47 30–34 682 783 713 536 1 396 319 8.42 35–39 684 224 703 803 1 388 027 8.37 40–44 483 437 500 719 984 156 5.93 45–49 369 988 393 527 763 515 4.60 50–54 360 130 409 250 769 380 4.64 55–59 319 093 370 486 689 579 4.16 60–64 232 929 310 156 543 085 3.27 65–69 157 661 240 966 398 627 2.40 70–74 112 069 169 150 281 219 1.69 75–79 71 156 105 568 176 724 1.07 80+ 60 839 103 740 164 579 0.99Age group MaleFemaleTotalPercent 0–14 2 427 277 2 316 266 4 743 543 28.59 15–64 5 264 451 5 562 946 10 827 397 65.26 65+ 401 725 619 424 1 021 149 6.15" ], [ "Vital statistics", "===UN estimates===PeriodPopulation(on 1 July)Live births Deaths Natural change CBR1CDR1NC1TFR1IMR1Life expectancy (years)19504 380 000  209 000  107 000  102 00047.724.423.36.63172.538.941951  4 485 000  213 000  108 000  105 00047.524.123.46.62170.939.251952  4 593 000  218 000  110 000  109 00047.523.923.66.63168.939.511953  4 702 000  224 000  112 000  112 00047.623.723.96.66167.539.741954  4 814 000  230 000  112 000  117 00047.723.324.46.69165.140.221955  4 931 000  236 000  114 000  122 00047.823.124.76.73163.440.451956  5 052 000  241 000  115 000  126 00047.822.824.96.75160.840.771957  5 176 000  247 000  116 000  130 00047.622.525.16.75158.241.191958  5 298 000  245 000  117 000  128 00046.222.024.26.57155.641.521959  5 419 000  244 000  117 000  127 00045.021.623.36.42152.541.791960  5 542 000  242 000  116 000  126 00043.721.022.76.25149.542.361961  5 665 000  242 000  116 000  127 00042.820.422.36.12147.042.791962  5 789 000  242 000  115 000  127 00041.919.922.06.00144.343.321963  5 914 000  242 000  114 000  128 00040.919.321.65.85141.743.901964  6 041 000  248 000  114 000  134 00041.018.922.15.86139.244.401965  6 171 000  252 000  115 000  137 00040.818.522.25.82136.944.791966  6 299 000  255 000  114 000  141 00040.518.122.45.77134.645.361967  6 426 000  258 000  115 000  143 00040.117.922.25.71132.345.511968  6 553 000  261 000  116 000  145 00039.817.722.15.65130.145.791969  6 680 000  263 000  116 000  147 00039.417.422.05.56128.046.241970  6 709 000  277 000  154 000  123 00040.722.618.15.72126.339.131971    276 000  150 000  40.922.318.65.87124.739.511972  6 766 000  283 000  148 000  136 00041.721.720.05.99121.940.221973  6 852 000  269 000  150 000  119 00039.221.817.45.56125.040.021974  6 913 000  240 000  150 000  90 00034.621.613.04.80126.939.801975  6 728 000  210 000578 000−368 00031.285.7 −54.64.10265.412.001976  6 307 000  175 000  548 000 −373 00027.686.6 −58.93.41173.112.011977  6 040 000  140 000  192 000 −52 00023.131.7 −8.72.72134.228.911978  5 961 000  171 000  136 000  35 00028.422.65.83.34131.236.981979  6 052 000  227 000  114 000  113 00037.919.118.84.56117.942.281980  6 199 000  301 000  104 000  198 00048.016.531.55.77115.847.571981  6 364 000  311 000  106 000  205 00049.116.732.46.04112.848.181982  6 620 000  333 000  109 000  224 00050.316.533.96.19109.448.741983  6 882 000  350 000  111 000  239 00051.016.134.86.30106.149.491984  7 134 000  367 000  113 000  254 00051.315.735.66.34102.750.241985  7 376 000  374 000  113 000  261 00050.615.335.46.3199.651.041986  7 661 000  380 000  114 000  266 00049.714.934.86.2396.751.511987  7 976 000  387 000  109 000  278 00048.713.735.06.1094.153.451988  8 270 000  393 000  109 000  284 00047.513.234.35.9491.254.281989  8 571 000  390 000  109 000  281 00045.612.732.95.7288.654.801990  8 911 000  398 000  109 000  289 00044.812.232.55.6486.255.431991  9 259 000  404 000  111 000  294 00043.812.031.85.5786.455.791992  9 718 000  406 000  113 000  294 00042.411.830.65.4586.456.021993  10 244 000414 000  117 000297 00040.811.529.35.2787.056.081994  10 636 000  411 000  121 000  290 00038.611.427.35.0588.356.041995  10 920 000  395 000  121 000  274 00036.211.125.14.8288.656.311996  11 183 000  377 000  121 000  256 00033.710.822.94.5989.056.351997  11 432 000  362 000  120 000  242 00031.710.521.24.3988.556.741998  11 669 000  343 000  118 000  225 00029.410.219.34.1487.257.031999  11 899 000  341 000  116 000  225 00028.79.718.93.9284.457.692000  12 119 000  334 000  112 000  222 00027.69.318.33.7779.958.632001  12 338 000  332 000  107 000  225 00026.98.718.33.6573.259.972002  12 562 000  332 000  102 000  230 00026.48.118.33.5666.461.232003  12 788 000  331 000  98 000  233 00025.97.618.23.4460.462.522004  13 016 000  332 000  95 000  237 00025.57.318.23.3555.363.552005  13 247 000  334 000  93 000  241 00025.27.018.13.2451.064.292006  13 478 000  336 000  92 000  244 00024.96.818.13.1547.465.062007  13 715 000  342 000  91 000  251 00024.96.618.33.0844.365.732008  13 944 000  341 000  90 000  252 00024.56.418.02.9741.366.472009  14 156 000  342 000 87 000  255 00024.16.118.02.8738.467.442010  14 364 000  340 000  88 000  252 00023.76.117.52.7735.767.712011  14 574 000  341 000  87 000  254 00023.45.917.42.7033.468.422012   14 787 000  345 000  87 000  258 00023.35.917.42.6631.068.922013  15 000 000  346 000  87 000  259 00023.05.817.22.6229.369.302014  15 211 000  347 000  88 000  259 00022.85.817.02.5927.869.742015  15 418 000  345 000  90 000  255 00022.35.816.52.5526.469.872016  15 625 000  342 000  90 000  252 00021.95.816.12.5125.370.222017  15 831 000  338 000  92 000  247 00021.35.815.62.4724.270.522018  16 025 000  334 000  94 000  240 00020.85.914.92.4423.370.562019  16 208 000  329 000  97 000  233 00020.35.914.32.4022.470.692020  16 397 000  326 000  102 000  223 00019.86.213.62.3821.670.422021  16 589 000  321 000  114 000  207 00019.36.812.52.3420.869.58 1 CBR = crude birth rate (per 1000); CDR = crude death rate (per 1000); NC = natural change (per 1000); TFR = total fertility rate (number of children per woman); IMR = infant mortality rate per 1000 births===Fertility===The total fertility rate in Cambodia was 3.0 children per woman in 2010.The fertility rate was 4.0 children in 2000.Women in urban areas have 2.2 children on average, compared with 3.3 children per woman in rural areas.", "Fertility is highest in Mondol Kiri and Rattanak Kiri Provinces, where women have an average of 4.5 children, and lowest in Phnom Penh where women have an average of 2.0 children.===Fertility and Births===Total Fertility Rate (TFR) (Wanted Fertility Rate) and Crude Birth Rate (CBR): Year CBR (Total) TFR (Total) CBR (Urban) TFR (Urban) CBR (Rural) TFR (Rural) 1995–1998 29.0 4.11 25.0 3.31 29.0 4.25 2000 27.7 4.0 (3.1) 23.9 3.1 (2.5) 28.3 4.2 (3.2) 2005 25.6 3.4 (2.8) 23.8 2.8 (2.3) 25.9 3.5 (2.9) 2010 24.2 3.0 (2.6) 21.0 2.2 (2.0) 25.0 3.3 (2.8) 2014 22.0 2.7 (2.4) 20.2 2.1 (1.9) 22.4 2.9 (2.6) 2021–22 20.2 2.7 (2.4) 20.5 2.4 (2.2) 20.1 3.0 (2.7)Total fertility rate per province in Cambodia in 2014Total fertility rate and other related statistics by province, as of 2014: Province Total fertility rate Percentage of women age 15-49 currently pregnant Completed fertility rate (Average number of children born per woman in her lifetime)Banteay Meanchey 2.8 5.2 4.0Kampong Cham 3.3 3.5 3.9Kampong Chhnang 2.4 5.4 4.2Kampong Speu 2.4 6.3 4.1Kampong Thom 2.9 5.8 4.4Kandal 2.5 5.7 3.9Kratié 3.6 7.3 4.5Phnom Penh 2.0 4.6 2.8Prey Veng 3.0 4.9 3.5Pursat 3.1 5.9 4.0Siem Reap 2.7 5.2 3.9Svay Rieng 2.5 5.7 3.4Takéo 2.4 3.9 3.7Oddar Meanchey 3.0 8.5 4.6Battambang/Pailin 2.9 5.5 3.8Kampot/Kep 2.5 4.9 3.9Sihanoukville/Koh Kong 2.7 5.8 4.1Preah Vihear/Stung Treng 3.6 9.5 5.2Mondulkiri/Ratanakiri 3.3 6.9 4.8===Infant and childhood mortality===Childhood mortality rates are decreasing in Cambodia.", "Currently, the infant mortality rate is 45 deaths per 1,000 live births for the five-year period before the survey compared with 66 deaths reported in the 2005 CDHS and 95 in the 2000 CDHS.", "Under-five mortality rates have also decreased from 124 deaths per 1,000 live births in 2000, 83 deaths in 2005 to 54 deaths per 1,000 in 2010.Childhood mortality decreases markedly with mother's education and wealth.", "Infant mortality, for example, is twice as high among children whose mothers have no schooling compared to those with secondary or higher education (72 versus 31).", "The association with wealth is even stronger.", "There are 77 deaths per 1,000 live births among infants from the poorest households compared to only 23 deaths per 1,000 live births among infants from the richest households.Mortality rates are much higher in rural than urban areas.", "Infant mortality, for example, is 64 deaths per 1,000 live births in rural areas compared to only 22 in urban areas.Mortality also differs by province.", "Infant mortality ranges from only 13 deaths per 1,000 live births in Phnom Penh to 78 deaths per 1,000 live births in Kampong Chhnang and Svay Rieng.===Life expectancy===Life expectancy in CambodiaIn 1959, life expectancy at birth was 44.2 years for males and 43.3 years for females.", "By 1970, life expectancy had increased by about 2.5 years since 1945.The greater longevity for females apparently reflected improved health practices during maternity and childbirth.PeriodLife expectancy inYearsPeriodLife expectancy inYears1950–195540.31985–199052.01955–196041.11990–199554.31960–196541.41995–200056.41965–197042.02000–200560.81970–197537.82005–201065.11975–198014.52010–201567.61980–198552.0Source: ''UN World Population Prospects''" ], [ "Ethnic groups", "An ethnic map of Cambodia from 1972.The largest of the ethnic groups in Cambodia are the Khmer, who comprise approximately 90% of the total population and primarily inhabit the lowland Mekong sub region and the central plains.The Khmer historically have lived near the lower Mekong River in a contiguous arc that runs from the southern Khorat Plateau where modern-day Thailand, Laos and Cambodia meet in the northeast, stretching southwest through the lands surrounding Tonle Sap lake to the Cardamom Mountains, then continues back southeast to the mouth of the Mekong River in southeastern Vietnam.Ethnic groups in Cambodia other than the politically and socially dominant Khmer are classified as either \"indigenous ethnic minorities\" or \"non-indigenous ethnic minorities\".", "The indigenous ethnic minorities, more commonly collectively referred to as the Khmer Loeu (\"upland Khmer\"), constitute the majority in the remote mountainous provinces of Ratanakiri, Mondulkiri and Stung Treng and are present in substantial numbers in Kratie Province.Approximately 17-21 separate ethnic groups, most of whom speak Austroasiatic languages related to Khmer, are included in the Khmer Loeu designation, including the Kuy and Tampuan people.", "These peoples are considered by the Khmer to be the aboriginal inhabitants of the land.", "Two of these highland groups, the Rade and the Jarai, are Chamic peoples who speak Austronesian languages descended from ancient Cham.", "These indigenous ethnic minorities haven't integrated into Khmer culture and follow their traditional animist beliefs.", "Ethnic group Population % of total* Khmer 13,684,985 90% Vietnamese 760,277 5.0% Chinese 152,055 1% Other 608,222 4%The non-indigenous ethnic minorities include immigrants and their descendants who live among the Khmer and have adopted, at least nominally, Khmer culture and language.", "The three groups most often included are the Chinese Cambodians, Vietnamese and Cham peoples.", "The Chinese have immigrated to Cambodia from different regions of China throughout Cambodia's history, integrating into Cambodian society and today Chinese Cambodians or Cambodians of mixed Sino-Khmer ancestry dominate the business community, politics and the media.", "The Cham are descendants of refugees from the various wars of the historical kingdom of Champa.", "The Cham live amongst the Khmer in the central plains but in contrast to the Khmer who are Theravada Buddhists, the vast majority of Cham follow Islam.There are also small numbers of other minority groups.", "Tai peoples in Cambodia include the Lao along the Mekong at the northeast border, Thai (urban and rural), and the culturally Burmese Kola, who have visibly influenced the culture of Pailin Province.", "Even smaller numbers of recent Hmong immigrants reside along the Lao border and various Burmese peoples have immigrated to the capital, Phnom Penh.Khmer 90%, Vietnamese 5%, Chinese 1%, other 4%." ], [ "Languages", ";Official languageKhmer is an Austroasiatic language spoken by over 90% of the Cambodian population.", "The vast majority of Khmer speakers use the '''Central Khmer''' dialect.", "Central Khmer is the variety spoken in the central plain where the ethnic Khmers most heavily concentrate.", "Other Khmer dialects include the Phnom Penh variety, as well as Northern Khmer (''Surin Khmer''), Western Khmer (''Cardamom Khmer''), Southern Khmer (''Khmer Krom''), and the Khmer Khe dialect in Stung Treng province.The Northern Khmer dialect is also spoken by over a million Khmers in the southern regions of Northeast Thailand.", "Western Khmer displays features of the Middle Khmer language, and is considered a conservative dialect.", "Southern Khmer is the first language of the Khmer Krom people in the Mekong Delta region in Vietnam.", ";Minority languages:According to Glottolog, 22 languages other than Khmer are spoken in Cambodia, most of which are also Austroasiatic languages.", "Other Austroasiatic languages of Cambodia include Kuy, Por (Pear), Somray, Chong, Suoy, Sa'och, Tampuan, Kaco', Stieng, Mnong, Brao, Krung (Rade), and Sou (Laven).Many of these languages are also spoken in Vietnam.", "Vietnamese itself is also spoken in parts of Cambodia.", "Non-Austroasiatic minority languages of Cambodia include Cham and Jarai (Austronesian) as well as Thai and Lao (Tai-Kadai).", ";Languages of educationEnglish and French are used to different extents in education.", ";Sign language* Cambodian Sign Language" ], [ "Religions", ":Buddhism: 97.1%, Islam: 2.0%, Christianity: 0.3%, Others: 0.5%" ], [ "CIA World Factbook demographic statistics", "The following demographic statistics are from the CIA World Factbook, unless otherwise indicated.", ":''Note'': estimates for this country take into account the effects of excess mortality due to AIDS; this can result in lower life expectancy, higher infant mortality, higher death rates, lower population growth rates, and changes in the distribution of population by age and sex than would otherwise be expected (July 2016 est.", ")===Population growth rate===* 1.56% (2016 est.", ")* 1.698% (2011 est.", ")* 1.71% (2010 est.", ")* 1.77% (2009 est.", ")* 1.75% (2008 est.", ")===Sex ratio===:At birth: 1.05 male(s)/female:0-14 years: 1.02 male(s)/female:15-24 years: 0.98 male(s)/female:25-54 years: 0.96 male(s)/female:55-64 years: 0.65 male(s)/female:65 years and over: 0.6 male(s)/female:Total Population: 0.94 male(s)/female (2016 est.", ")===Life expectancy at birth===:Total population: 64.5 years:Male: 62 years:Female: 67.1 years (2016 est.", ")===HIV/AIDS===Adult prevalence rate:0.63% (2015 est.", ")People living with HIV/AIDS:74,100 (2015 est.", "):63,000 (2009 est.", "):75,000 (2007 est.", ")Deaths:1,000 (2011 est.", "):2,000 (2015 est.", "):3,100 (2009 est.", "):6,900 (2007 est.", ")===Nationality===:Noun: Cambodian(s) or Khmer(s):Adjective: Cambodian or Khmer===Urbanization===:Urban population: 39.4% of total population (2019):Rate of urbanization: 7.8% annual rate of change (2008—2019)===Literacy===:Definition: age 15 and over can read and write:Total population: 88.5%:Male: 91.1%:Female: 86.2% (2019)===Education expenditure===:1.9% of GDP (2014)===Diaspora===Countries with notable populations of Cambodians are:****************" ], [ "References" ] ]

[ [ "Politics of Cambodia" ], [ "Introduction", "The '''politics of Cambodia''' are defined within the framework of a constitutional monarchy, in which the king serves as the head of state, and the prime minister is the head of government.", "The collapse of communism set in motion events that led to the withdrawal of the Vietnamese armed forces, which had established their presence in the country since the fall of the Khmer Rouge.", "The 1993 constitution, which is currently in force, was promulgated as a result of the 1991 Paris Peace Agreements, followed by elections organized under the aegis of the United Nations Transitional Authority in Cambodia.", "The constitution declares Cambodia to be an \"independent, sovereign, peaceful, permanently neutral and non-aligned country.\"", "The constitution also proclaims a liberal, multiparty democracy in which powers are devolved to the executive, the judiciary and the legislature.", "However, there is no effective opposition to the Prime Minister Hun Sen, who has been in power from 1984 up to 2023.His Cambodian People's Party won all 125 seats in the National Assembly in 2018 after the banning of opposition party CNRP and KNLF.", "KNLF became a main opposition exiled in Denmark after CNRP was dissolved.", "During the communal election in 2022 and the national election in 2023, there were no international observers.", "The government is considered to be autocratic.Executive power is exercised by the Royal Government, on behalf of and with the consent of the monarch.", "The government is constituted of the Council of Ministers, headed by the prime minister.", "The prime minister is aided in his functions by members of the Council such as deputy prime ministers, senior ministers and other ministers.", "Legislative power is vested in a bicameral legislature composed of the National Assembly, which has the power to vote on draft law, and the Senate, that has the power of review.", "Upon passage of legislation through the two chambers, the draft law is presented to the monarch for signing and promulgation.", "The judiciary is tasked with the protection of rights and liberties of the citizens, and with being an impartial arbiter of disputes.", "The Supreme Court is the highest court of the country and takes appeals from lower courts on questions of law.", "A separate body called the Constitutional Council was established to provide interpretations of the constitution and the laws, and also to resolve disputes related to election of members of the legislature.The Cambodian People's Party has dominated the political landscape since the 1997 coup d'état in Phnom Penh.", "Other prominent political parties include the royalist FUNCINPEC and the erstwhile Cambodia National Rescue Party that was dissolved by the Supreme Court in 2017.Comparative political scientists Steven Levitsky and Lucan Way have described Cambodia as a \"competitive authoritarian regime\", a hybrid regime type with important characteristics of both democracy and authoritarianism.In July 2023 election, the ruling Cambodian People’s Party (CPP) easily won by landslide in flawed election, after disqualification of Cambodia’s most important opposition, Candlelight Party.", "On 22 August 2023, Hun Manet, son of Hun Sen, was sworn in as the new Cambodian prime minister." ], [ "Legal framework", "Cambodia is a constitutional monarchy with a unitary structure and a parliamentary form of government.", "The constitution, which prescribes the governing framework, was promulgated in September 1993 by the Constituent Assembly that resulted from the 1993 general election conducted under the auspices of the United Nations Transitional Authority in Cambodia (UNTAC).", "The assembly adopted the basic principles and measures mandated under the Paris Peace Agreements into the text of the constitution.", "Assimilated into the governing charter, these provisions place the constitution as the supreme law of the land; declare Cambodia's status as a sovereign, independent and neutral state; enshrine a liberal, multi-party democracy with fair and periodic elections; guarantee respect for human rights; and provide for an independent judiciary.The brutality of the Democratic Kampuchea regime had especially necessitated the inclusion of provisions concerning human rights in order to prevent a return to the policies and practices of the past.", "These criteria had been drawn from the Namibian constitution drafting process that took place in 1982.German constitutional law scholar, Jörg Menzel, characterized these benchmarks as the \"necessary nucleus of a modern constitutional state.\"", "The constitution further sanctifies the status of international law in the issue of human rights by binding Cambodia to \"respect\" the provisions of human rights treaties adopted by the UN.", "The 1993 constitution has been amended eight times since its passage – in 1994, 1999, 2001, 2005, 2006, 2008, 2014 and 2018.=== Separation of powers ===The powers are devolved to three branches of the state: the legislature, the executive and the judiciary, in recognition of the doctrine of separation of powers.", "Political sovereignty rests with the Cambodian people, who exercise their power through the three arms of the state.", "The Royal Government, which wields executive power, is directly responsible to the National Assembly.", "The judiciary, which is an independent power, is tasked with the protection of citizens' rights and liberties.", "Buddhism is proclaimed as the state religion.=== Influences on legal system ===The legal system of Cambodia is civil law and has been strongly influenced by the legal heritage of France as a consequence of colonial rule.", "The Soviet-Vietnamese system dominated the country from 1981 until 1989, and Sri Lankan jurist Basil Fernando argues that its elements are present in the current system as well.", "The role of customary law, based on Buddhist beliefs and unwritten law drawn from the Angkorean period, is also prevalent.=== Market economy ===The constitution contains a commitment to the \"market economy system\", which along with accompanying provisions effects a fundamental change in the role of the state from the past.", "Security of private property and the right to sell and exchange freely, necessary conditions for the functioning of the market economy, are provided for.", "The state's powers of expropriation are limited to the extent they serve public interest, to be exercised only when \"fair and just\" compensation is made in advance.", "Operating under the slogan ''Le Cambodge s'aide lui-même'' or \"Cambodia will help itself\", one of the earliest undertakings of the Royal Government was to implement programs to ensure the economic rehabilitation of Cambodia and its integration in the regional and global economies.", "On 10 March 1994, the Royal Government declared an \"irreversible and irrevocable\" move away from a centrally-planned economy towards a market-oriented economy." ], [ "Monarchy", "King Norodom SihamoniCambodia is a constitutional monarchy.", "The king is officially the head of state and is the symbol of unity and \"perpetuity\" of the nation, as defined by Cambodia's constitution.From September 24, 1993, through October 7, 2004, Norodom Sihanouk reigned as king, after having previously served in a number of offices (including king) since 1941.Under the constitution, the king has no political power, but as Norodom Sihanouk was revered in the country, his word often carried much influence in the government.", "The king, often irritated over the conflicts in his government, several times threatened to abdicate unless the political factions in the government got along.", "This put pressure on the government to solve their differences.", "This influence of the king was often used to help mediate differences in government.After the abdication of King Norodom Sihanouk in 2004, he was succeeded by his son Norodom Sihamoni.", "While the retired king was highly revered in his country for dedicating his lifetime to Cambodia, the current king has spent most of his life abroad in France.", "Thus, it remains to be seen whether the new king's views will be as highly respected as his father's.Although in the Khmer language there are many words meaning \"king\", the word officially used in Khmer (as found in the 1993 Cambodian constitution) is ''preăhmôhaksăt'' (Khmer regular script: ព្រះមហាក្សត្រ), which literally means: ''preăh''- (\"excellent\", cognate of the Pali word vara) -''môha''- (from Sanskrit, meaning \"great\", cognate with \"maha-\" in maharaja) -''ksăt'' (\"warrior, ruler\", cognate of the Sanskrit word kṣatrá).On the occasion of King Norodom Sihanouk's retirement in September 2004, the Cambodian National Assembly coined a new word for the retired king: ''preăhmôhavireăkksăt'' (Khmer regular script: ព្រះមហាវីរក្សត្រ), where ''vireăk'' comes from Sanskrit ''vīra'', meaning \"brave or eminent man, hero, chief\", cognate of Latin ''vir'', ''viris'', English ''virile''.", "''Preăhmôhavireăkksăt'' is translated in English as \"King-Father\" (), although the word \"father\" does not appear in the Khmer noun.As ''preăhmôhavireăkksăt'', Norodom Sihanouk retained many of the prerogatives he formerly held as ''preăhmôhaksăt'' and was a highly respected and listened-to figure.", "Thus, in effect, Cambodia could be described as a country with two Kings during Sihanouk's lifetime: the one who was the head of state, the ''preăhmôhaksăt'' Norodom Sihamoni, and the one who was not the head of state, the ''preăhmôhavireăkksăt'' Norodom Sihanouk.Sihanouk died of a pulmonary infarction on October 15, 2012.===Succession to the throne===Unlike most monarchies, Cambodia's monarchy is not necessarily hereditary and the king is not allowed to select his own heir.", "Instead, a new king is chosen by a Royal Council of the Throne, consisting of the president of the National Assembly, the prime minister, the president of the Senate, the first and second vice presidents of the Senate, the chiefs of the orders of Mohanikay and Thammayut, and the first and second vice-president of the assembly.", "The Royal Council meets within a week of the king's death or abdication and selects a new king from a pool of candidates with royal blood.It has been suggested that Cambodia's ability to peacefully appoint a new king shows that Cambodia's government has stabilized incredibly from the situation the country was in during the 1970s (see History of Cambodia)." ], [ "Executive branch", "Hun Sen – Prime Minister 1998–2023Seal of the Royal GovernmentThe prime minister of Cambodia is a representative from the ruling party of the National Assembly.", "The prime minister is appointed by the king on the recommendation of the president and vice presidents of the National Assembly.", "The prime minister must receive be given a vote of confidence by the National Assembly.The prime minister is officially the head of government in Cambodia.", "The prime minister appoints a Council of Ministers.", "Officially, the prime minister's duties include chairing meetings of the Council of Ministers (Cambodia's version of a cabinet) and appointing and leading a government.", "The prime minister and the government make up Cambodia's executive branch of government.The current prime minister is Cambodian People's Party (CPP) member Hun Manet.", "He has held this position since 2023.Result 1998 election, one year after the CPP staged a bloody coup in Phnom Penh to overthrow elected Prime Minister Prince Norodom Ranariddh, president of the FUNCINPEC party." ], [ "Legislative branch", "The legislative branch of the Cambodian government is made up of a bicameral parliament.", "* The '''National Assembly''' ( ) has 125 members, elected for a five-year term by proportional representation.", "* The '''Senate''' ( ) has 61 members.", "Two of these members are appointed by the king, two are elected by the lower house of the government, and the remaining fifty-seven are elected popularly by \"functional constituencies\".", "Members in this house serve a six-year term.The official duty of the Parliament is to legislate and make laws.", "Bills passed by the Parliament are given to the king who gives the proposed bills royal assent.", "The king does not have veto power over bills passed by the National Assembly and thus, cannot withhold royal assent.", "The National Assembly also has the power to dismiss the prime minister and his government by a two-thirds vote of no confidence.===Senate===The upper house of the Cambodian legislature is called the ''Senate''.", "It consists of sixty-one members.", "Two of these members are appointed by the king, two are elected by the lower house of the government, and the remaining fifty-seven are elected popularly by electors from provincial and local governments, in a similar fashion to the Senate of France.", "Members in this house serve six-year terms.Prior to 2006, elections had last been held for the Senate in 1999.New elections were supposed to have occurred in 2004, but these elections were initially postponed.", "On January 22, 2006, 11,352 possible voters went to the poll and chose their candidates.", "This election was criticized by local monitoring non-governmental organizations as being undemocratic., the Cambodian People's Party holds forty-three seats in the Senate, constituting a significant majority.", "The two other major parties holding seats in the Senate are the Funcinpec party (holding twelve seats) and the Sam Rainsy Party (holding two seats).===National Assembly===The lower house of the legislature is called the ''National Assembly''.", "It is made up of 125 members, elected by popular vote to serve a five-year term.", "Elections were last held for the National Assembly in July 2013.To vote in legislative elections, one must be at least eighteen years of age.", "However, to be elected to the legislature, one must be at least twenty-five years of age.The National Assembly is led by a president and two vice presidents who are selected by the assembly members prior to each session., the Cambodian People's Party holds all 125 seats in the National Assembly." ], [ "Political parties and elections", "Former opposition leader and CNRP president Sam RainsyFormer First Prime Minister and FUNCINPEC president Norodom Ranariddh===2018 general election results===" ], [ "Judicial branch", "The judicial branch is independent from the rest of the government, as specified by the Cambodian Constitution.", "The highest court of judicial branch is the Supreme Council of the Magistracy.", "Other, lower courts also exist.", "Until 1997, Cambodia did not have a judicial branch of government despite the nation's Constitution requiring one.", "In 2003, Judge Kim Sathavy was in charge of establishing the first Royal School for Judges and Prosecutors to train a new generation of magistrates and legal clerks for Cambodia.The main duties of the judiciary are to prosecute criminals, settle lawsuits, and, most importantly, protect the freedoms and rights of Cambodian citizens.", "However, in reality, the judicial branch in Cambodia is highly corrupt and often serves as a tool of the executive branch to silence civil society and its leaders.", "There are currently 17 justices on the Supreme Council." ], [ "Foreign relations", "Cambodia is a member of the ACCT, AsDB, ASEAN, ESCAP, FAO, G-77, IAEA, IBRD, ICAO, ICC, ICRM, IDA, IFAD, IFC, IFRCS, ILO, IMF, IMO, Intelsat (nonsignatory user), International Monetary Fund, Interpol, IOC, ISO (subscriber), ITU, NAM, OPCW, PCA, UN, UNCTAD, UNESCO, UNIDO, UPU, WB, WFTU, WHO, WIPO, WMO, WTO, WToO, WTrO (applicant)=== International rankings === Organization \t Survey \t Ranking Score Transparency International Corruption Perceptions Index (2021) 157 out of 180 87.22% United Nations Development Programme \tHuman Development Index (2021) 146 Out of 191 76.43% World Gold Council Gold reserve (2010) 65 Out of 110 60% Reporters Without Borders Worldwide Press Freedom Index (2012) 117 out of 179 65.3% The Heritage Foundation Indices of Economic Freedom (2012) 102 Out of 179 57% Global Competitiveness Report World Economic Forum (2012) 97 out of 142 68.3%" ], [ "Provincial and local governments", "Below the central government are 24 provincial and municipal administration.", "(In rural areas, first-level administrative divisions are called provinces; in urban areas, they are called municipalities.)", "The administrations are a part of the Ministry of the Interior and their members are appointed by the central government.", "Provincial and municipal administrations participate in the creation of nation budget; they also issue land titles and license businesses.Since 2002, commune-level governments (commune councils) have been composed of members directly elected by commune residents every five years.In practice, the allocation of responsibilities between various levels of government is uncertain.", "This uncertainty has created additional opportunities for corruption and increased costs for investors." ], [ "Citations" ], [ "References", "**" ], [ "External links", "* Global Integrity Report: Cambodia reports on corruption and anti-corruption in Cambodia===Royalty===* King of Cambodia, Norodom Sihamoni Official Website of King Norodom Sihamoni* King of Cambodia, Norodom Sihanouk Official Website of former King Norodom Sihanouk===Official===* Cambodia.gov.kh Official Royal Government of Cambodia Website (English Version) ( Cambodia.gov.kh Khmer Version)* CDC Council for the Development of Cambodia* Conseil Constitutionnel du Cambodge Constitution council of Cambodia* Department of Fisheries* Food Security and Nutrition Information System Cambodia* Ministry of Commerce* Ministry of Culture and Fine Arts* Ministry of Economy and Finance* Ministry of Education, Youth and Sport* Ministry of Environment* Ministry of Posts and Telecommunications* Ministry of Public Works and Transport* Ministry of Tourism* NiDA National Information Communications Technology Development Authority* Ministry of Planning* NIS National Institute of Statistics of Cambodia* Ministry of Interior* N.C.C.T National Committee for Counter Trafficking in person===Other===* Constitution of Cambodia" ] ]

[ [ "Economy of Cambodia" ], [ "Introduction", "Real GPD per capita development of CambodiaThe '''economy of Cambodia''' ( ) currently follows an open market system (market economy) and has seen rapid economic progress in the last decade.", "Cambodia had a GDP of $28.54 billion in 2022.Per capita income, although rapidly increasing, is low compared with most neighboring countries.", "Cambodia's two largest industries are textiles and tourism, while agricultural activities remain the main source of income for many Cambodians living in rural areas.", "The service sector is heavily concentrated on trading activities and catering-related services.", "Recently, Cambodia has reported that oil and natural gas reserves have been found off-shore.In 1995, with a GDP of $2.92 billion the government transformed the country's economic system from a planned economy to its present market-driven system.", "Following those changes, growth was estimated at a value of 7% while inflation dropped from 26% in 1994 to only 6% in 1995.Imports increased due to the influx of foreign aid, and exports, particularly from the country's garment industry, also increased.", "Although there was a constant economic growth, this growth translated to only about0.71% for the ASEAN economy in 2016, compared with her neighbor Indonesia, which contributed 37.62%.After four years of improving economic performance, Cambodia's economy slowed in 1997–1998 due to the regional economic crisis, civil unrest, and political infighting.", "Foreign investments declined during this period.", "Also, in 1998 the main harvest was hit by drought.", "But in 1999, the first full year of relative peace in 30 years, progress was made on economic reforms and growth resumed at 4%.Currently, Cambodia's foreign policy focuses on establishing friendly borders with its neighbors (such as Thailand and Vietnam), as well as integrating itself into regional (ASEAN) and global (WTO) trading systems.", "Some of the obstacles faced by this emerging economy are the need for a better education system and the lack of a skilled workforce; particularly in the poverty-ridden countryside, which struggles with inadequate basic infrastructure.", "Nonetheless, Cambodia continues to attract investors because of its low wages, plentiful labor, proximity to Asian raw materials, and favorable tax treatment." ], [ "Recent economic history", "Following its independence from France in 1953, the Cambodian state has undergone five periods of political, social, and economic transformation:# First Kingdom of Cambodia (1953–1970)# Khmer Republic (1970–1975)# Democratic Kampuchea (1975–1982, ousted in 1979); became Coalition Government of Democratic Kampuchea in exile (1982–1993)# People's Republic of Kampuchea (1979–1989), later renamed \"State of Cambodia\" (1989–1993) # Second Kingdom of Cambodia (1993–present)In 1989, the State of Cambodia implemented reform policies that transformed the Cambodian economic system from a command economy to an open market one.", "In line with the economic reformation, private property rights were introduced and state-owned enterprises were privatized.", "Cambodia also focused on integrating itself into regional and international economic blocs, such as the Association of South East Asian Nations and the World Trade Organization respectively.", "These policies triggered a growth in the economy, with its national GDP growing at an average of 6.1% before a period of domestic unrest and regional economic instability in 1997 (1997 Asian financial crisis).", "However, conditions improved and since 1999, the Cambodian economy has continued to grow at an average pace of approximately 6–8% per annum.In 2007, Cambodia's gross domestic product grew by an estimated 18.6%.", "Garment exports rose by almost 8%, while tourist arrivals increased by nearly 35%.", "With exports decreasing, the 2007 GDP growth was driven largely by consumption and investment.", "Foreign direct investment (FDI) inflows reached US$600 million (7 percent of GDP), slightly more than what the country received in official aid.", "Domestic investment, driven largely by the private sector, accounted for 23.4 percent of GDP.", "Export growth, especially to the US, began to slow in late 2007 accompanied by stiffer competition from Vietnam and emerging risks (a slowdown in the US economy and lifting of safeguards on China's exports).", "US companies were the fifth largest investors in Cambodia, with more than $1.2 billion in investments over the period 1997–2007.Cambodia was severely damaged by the financial crisis of 2007–2008, and its main economic sector, the garment industry, suffered a 23% drop in exports to the United States and Europe.", "As a result, 60,000 workers were laid off.", "However, in the last quarter of 2009 and early 2010, conditions were beginning to improve and the Cambodian economy began to recover.", "Cambodian exports to the US for the first 11 months of 2012 reached $2.49 billion, a 1 per cent increase year-on-year.", "Its imports of US goods grew 26 per cent for that period, reaching $213 million.", "Another factor underscoring the potential of the Cambodian economy is the recent halving of its poverty rate.", "The poverty rate is 20.5 per cent, meaning that approximately 2.8 million people live below the poverty line." ], [ "Data", "The following table shows the main economic indicators in 1986–2020 (with IMF staff estimates in 2021–2026).", "Inflation below 5% is in green.", "The annual unemployment rate is extracted from the World Bank, although the International Monetary Fund find them unreliable.YearGDP(in Bil.", "US$PPP)GDP per capita(in US$ PPP)GDP(in Bil.", "US$nominal)GDP per capita(in US$ nominal)GDP growth(real)Inflation rate(in Percent)Unemployment(in Percent)Government debt(in % of GDP)1986n/an/a0.225.71n/an/an/an/a19874.3516.020.117.1n/a-31.2%n/an/a19884.8569.10.332.69.6%23.0%n/an/a19895.2593.10.339.73.3%63.8%n/an/a19905.4602.50.999.81.1%141.8%n/an/a19916.0647.52.0215.77.6%191.0%0.7%n/a19926.6684.42.4252.57.1%75.0%0.8%n/a19937.0703.62.4242.54.0%114.3%0.8%n/a19947.8745.92.8265.18.2%10.4%1.3%n/a19958.4781.73.4319.56.0%10.1%0.8%n/a19969.1818.53.5316.25.9%7.1%0.8%30.2%19979.6842.83.4302.24.0%10.5%0.9%31.6%199810.2870.13.1267.94.7%12.9%0.9%37.2%199911.6971.93.5293.712.7%2.0%0.9%34.7%200013.01,065.43.7300.09.6%-0.8%1.0%35.2%200114.41,158.34.0320.08.6%-0.1%1.0%34.9%200215.61,230.74.3337.56.6%0.0%1.1%39.7%200317.31,336.54.7360.78.5%1.0%1.1%43.1%200419.61,489.65.3405.610.3%3.9%1.1%42.7%200522.91,712.66.3470.713.3%6.3%1.1%35.6%200626.11,925.87.3536.210.8%6.1%1.2%30.7%200729.52,149.08.6627.810.2%7.7%1.3%29.4%200832.12,305.010.3741.96.7%25.0%0.8%27.0%200932.42,299.110.4737.20.1%-0.7%0.6%28.5%201034.72,437.811.2788.26.0%4.0%0.8%28.7%201138.02,635.912.8889.87.1%5.5%0.6%29.7%201242.42,912.114.1965.47.3%2.9%0.5%31.5%201345.83,109.915.21,034.87.4%3.0%0.4%31.7%201448.73,271.916.71,123.27.1%3.9%0.7%31.9%201552.63,500.618.11,203.57.0%1.2%0.4%31.2%201657.93,816.820.01,320.36.9%3.0%0.7%29.1%201762.84,097.522.21,446.97.0%2.9%0.1%30.0%201869.24,466.824.41,578.07.5%2.4%0.1%28.6%201975.44,832.726.71,713.37.0%2.0%0.1%29.0%202073.64,695.126.01,655.4-3.5%2.9%0.3%31.6%202178.14,930.027.21,720.24.2%3.1%n/a33.4%202284.65,289.929.11,820.96.0%2.8%n/a35.4%202392.05,693.431.31,938.26.3%3.0%n/a38.0%2024100.16,136.533.82,072.16.6%3.0%n/a41.0%2025108.96,610.236.52,217.56.7%3.0%n/a43.9%2026118.57,119.039.52,375.36.8%3.0%n/a46.7%" ], [ "Economic sectors", "=== Garment industry ===The garment industry represents the largest portion of Cambodia's manufacturing sector, accounting for 80% of the country's exports.", "In 2012, the exports grew to $4.61 billion up 8% over 2011.In the first half of 2013, the garment industry reported exports worth $1.56 billion.", "The sector employs 335,400 workers, of which 91% are female.The sector operates largely on the final phase of garment production, that is turning yarns and fabrics into garments, as the country lacks a strong textile manufacturing base.", "In 2005, there were fears that the end of the Multi Fibre Arrangement would threaten Cambodia's garment industry; exposing it to stiff competition with China's strong manufacturing capabilities.", "On the contrary, Cambodia's garment industry at present continues to grow rapidly.", "This is can be attributed to the country's open economic policy which has drawn in large amounts of foreign investment into this sector of the economy.Garment Factories by Ownership Nationality in 2010: Nationality of Ownership Ownership by percentage Number of factories owned Taiwan 28% 66 China 19% 44 Hong Kong 17% 39 South Korea 13% 31 Malaysia 6% 14 Cambodia 5% 13 Singapore 4% 10 USA 4% 9 Others 4% 10A garment factory worker in Cambodia undertaking health precautionsIn 2010, 236 garment export-oriented factories were operating and registered with GMAC, the Garment Manufacturers Association in Cambodia, with 93% being foreign direct investment (FDI).As seen in the table above, Cambodia's garment industry is characterized by a small percentage of local ownership.", "This is a reflection of the deficiency of skilled workers in the country as well as the limited leverage and autonomy Cambodian factories have in strategic decisions.", "Another characteristic of the industry is the country's competitive advantage as the only country where garment factories are monitored and reported according to national and international standards.This has allowed Cambodia to secure its share of quotas for exports to the US through the US-Cambodia Trade Agreement on Textiles and Apparel (1999–2004), which linked market access to labor standards.", "However, the Cambodian garment industry remains vulnerable to global competition due to a lack of adequate infrastructure, labor unrest, the absence of a domestic textile industry, and almost complete dependence on imported textile material.GMAC is establishing a specialized training institute to train garment workers.", "The institute is in Phnom Penh Special Economic Zone and will be completed by late 2016.It aims to train 1,600 garment workers in the first three years and 240 university students each year as part of a separate program.=== Agriculture ===Cambodians planting rice, 2004.Agriculture is the traditional mainstay of the Cambodian economy.", "Agriculture accounted for 90 percent of GDP in 1985 and employed approximately 80 percent of the work force.", "Rice is the principal commodity.Major secondary crops include maize, cassava, sweet potatoes, groundnuts, soybeans, sesame seeds, dry beans, and rubber.", "The principal commercial crop is rubber.", "In the 1980s it was an important primary commodity, second only to rice, and one of the country's few sources of foreign exchange.=== Tourism ===In the 1960s, Cambodia was a prominent tourist destination in the Southeast Asian region.", "Due to protracted periods of civil war, insurgencies, and especially the genocidal regime of the Khmer Rouge (see Khmer Rouge Genocide), Cambodia's tourism industry was reduced to being virtually non-existent.", "Since the late 1990s, tourism is fast becoming Cambodia's second largest industry, just behind the garment manufacturing.", "In 2006, Cambodia's tourism sector generated a revenue of US$1.594 billion, which made up approximately 16% of the country's GDP.Angkor Wat in Siem Reap, Cambodia.Cultural heritage tourism is especially popular in the country, with many foreign tourists visiting the ancient Hindu temple of Angkor Wat located in the Siem Reap province.", "Other popular tourist attractions include the Royal Palace, Phnom Penh, as well as ecotourism spots such as Tonlé Sap Lake and the Mekong River.The tourism industry in Cambodia has been perpetuated by the development of important transportation infrastructure; in particular Cambodia's two international airports in Phnom Penh and Siem Reap respectively.", "To the Cambodian economy, tourism has been a means for the accumulation of foreign currency earnings and employment for the Cambodian workforce, with about 250,000 jobs generated in 2006.Meanwhile, challenges to the industry include leakage of revenue to foreign markets due to a dependence on foreign goods as well as the prevalence of the Child sex tourism industry.=== Gambling industry ===Russian Federation Boulevard in Phnom Penh.=== Construction ===The increase in tourist arrivals has led to growing demand for hotels and other forms of accommodation surrounding tourist hotspots.", "Siem Reap in particular has seen a construction boom in recent years.", "The capital Phnom Penh has also witnessed a growth in the construction and real estate sector.", "Recently, planned projects that have been on the pipeline for several years have been shelved temporarily due to a reduction in foreign investment.From 2009, the Cambodian government has allowed foreigners to own condominiums.", "This has helped in attracting real estate investors from Thailand, Malaysia, Singapore and other countries.The construction sector attracted investment of $2.1 billion in 2012 which is a 72 per cent rise compared with 2011.Construction licenses issued stood at 1,694 projects in 2012, which was 20% lower than 2011 but they were higher in value.=== Resources ===Oil seeps were discovered in Cambodia as early as the 1950s by Russian and Chinese geologists.", "Development of the industry was delayed, however, by the Vietnam and Cambodian Civil Wars and the political uncertainty that followed.", "Further discoveries of oil and natural gas deposits offshore in the early 2000s led to renewed domestic and international interest in Cambodia's production possibilities.", "As of 2013, the US company Chevron, Japanese JOGMEC and other international companies maintained production sites both on shore and off.", "Chevron alone had invested over US$160 million and drilled 18 wells.Sok Khavan, acting director general of the Cambodian National Petroleum Authority, estimated that once the contracts are finalized and legal issues resolved, the Cambodian government will receive approximately 70% of the revenues, contributing to an economy in which the GDP is projected to increase five-fold by 2030.In addition, there are 10,000 square miles offshore in the Gulf of Thailand that holds potential reserves of 12-14 trillion cubic feet of natural gas and an unspecified amount of oil.", "The rights to this territory are currently a subject of dispute between Cambodia and Thailand, further delaying any possible production developments.", "In early 2013 it was reported that the two countries were close to a deal that would allow joint production to begin.===Foreign aid===Rice milling is very important to the Cambodian economy.Cambodia's emerging democracy has received strong international support.", "Under the mandate of the United Nations Transitional Authority in Cambodia (UNTAC), $1.72 billion (1.72 G$) was spent in an effort to bring basic security, stability and democratic rule to the country.", "Various news and media reports suggest that since 1993 the country has been the recipient of some US$10 billion in foreign aid.With regards to economic assistance, official donors had pledged $880 million at the Ministerial Conference on the Rehabilitation of Cambodia (MCRRC) in Tokyo in June 1992.In addition to that figure, $119 million was pledged in September 1993 at the International Committee on the Reconstruction of Cambodia (ICORC) meeting in Paris, and $643 million at the March 1994 ICORC meeting in Tokyo.Cambodia experienced a shortfall in foreign aid in the year 2005 due to the government's failure to pass anti-corruption laws, opening up a single import/export window, increasing its spending on education, and complying with policies of good governance.", "In response, the government adopted the National Strategic Development Plan for 2006–10 (also known as the “Third Five-Year Plan”).", "The plan focused on three major areas:* the speeding up of economic growth at an annual rate of 6-7%* eradicating corruption* developing public structures in favor of quality (i.e.", "by education, training, and healthcare) over quantity (i.e.", "rapid population growth)=== Banking ===There are no significant barriers to bank entry.", "At the end of 2013, there stood 35 commercial banks.", "Since 2011 new bankswith offshore funding have begun to enter the market.=== Telecommunications ====== Energy ===Cambodia has significant potential for developing renewable energy and could potentially run its energy system on 100% renewable sources.", "The country, however, remains one of the few countries in the ASEAN region that has not adopted renewable energy targets.", "To attract more investment in renewable energy Cambodia could adopt targets, improve renewable energy governance, develop a regulatory framework, improve project bankability and facilitate market entry for international investors.", "Due to high vulnerability to climate change, it is recommended that Cambodia focuses on developing renewable energy away from fossil fuels as part of climate change mitigation measures.=== Transport ====== Child labour ====== Trade - EBA Issues ===The announcement from February 12, 2020 was to suspend EBA (\"Everything But Arms\") trade preferences between EU and Cambodia.", "The country has known to be the second largest beneficiary from EBA's program.", "The EU's preliminary conclusion sent to Cambodian government in November 12, 2019 because Cambodia failed to address serious human and labor rights concerns under Human Rights Watch.", "Moreover, the issue behind ending the opposition party (CNRP) and dropping charges against the leader of CNRP violated the right to freedom of expression." ], [ "Challenges for industrial development", "Although Cambodia exports mainly garments and products from agriculture and fisheries, it is striving to diversify the economy.", "There is some evidence of expansion in value-added exports from a low starting point, largely thanks to the manufacture of electrical goods and telecommunications by foreign multinationals implanted in the country.", "Between 2008 and 2013, high-tech exports climbed from just US$3.8million to US$76.5 million.It will be challenging for Cambodia to enhance the technological capacity of the many small and medium-sized enterprises (SMEs) active in agriculture, engineering and the natural sciences.", "Whereas the large foreign firms in Cambodia that are the main source of value-added exports tend to specialize in electrical machinery and telecommunications, the principal task for science and technology policy will be to facilitate spillovers in terms of skills and innovation capability from these large operators towards smaller firms and across other sectors.There is little evidence that the Law on Patents, Utility Model Certificates and Industrial Designs (2006) has been of practical use, thus far, to any but the larger foreign firms operating in Cambodia.", "By 2012, 27 patent applications had been filed, all by foreigners.", "Of the 42 applications for industrial design received up to 2012, 40 had been filed by foreigners.", "Nevertheless, the law has no doubt encouraged foreign firms to introduce technological improvements to their on-shore production systems, which can only be beneficial." ], [ "Statistics", "; Investment (gross fixed) : 3% of GDP (2011 est.", ");Household income or consumption by percentage share* lowest 10%: 2.6%* highest 10%: 23.7% (2011); Agriculture - products * rice, * rubber, * corn, * vegetables, * cashews, * tapioca, * silk; Industries* tourism, garments, construction, rice milling, fishing, wood and wood products, rubber, cement, gem mining, textiles; Industrial production growth rate* 5.7% (2011 est.", "); Electricity ... 2010 2011 production 1.273 billion kWh ... consumption 1.272 billion kWh ... exports 0 kWh ... imports 274 million kWh ... ; Exchange rates Year Riels (KHR) per US dollar 2012 4,097 2011 4,395.62 2010 4,145 2009 4,139.33 2008 4,070.94 2007 4,006 2006 4,103" ], [ "See also", "* Special Economic Zones of Cambodia* Cambodia and the World Bank" ], [ "Sources" ], [ "References", "*" ], [ "External links", "* CAMBODIA INVESTMENT GUIDEBOOK 2013 (Council for the Development of Cambodia)" ] ]

[ [ "Telecommunications in Cambodia" ], [ "Introduction", "Sihanoukville - communication towers.", "'''Telecommunications in Cambodia''' include telephone, radio, television, and Internet services, which are regulated by the Ministry of Posts and Telecommunications.", "Transport and posts were restored throughout most of the country in the early 1980s during the People's Republic of Kampuchea regime after being disrupted under Democratic Kampuchea (Khmer Rouge).In January 1987, the Soviet-aided Intersputnik space communications station began operation in Phnom Penh and established two-way telecommunication links between the Cambodian capital and the cities of Moscow, Hanoi, Vientiane and Paris.", "The completion of the earth satellite station restored the telephone and telex links among Phnom Penh, Hanoi, and other countries for the first time since 1975.Although telecommunications services were initially limited to the government, these advances in communications helped break down the country's isolation, both internally and internationally.Today, with the availability of mobile phones, communications are open to all, though the country's Prime Minister Hun Sen decreed that 3G mobile phones would not be allowed to support video calling." ], [ "Telephones", "As of Q1 2020, Cambodia's mobile connection is at 21.4 million.", "Smart Axiata, a leading telecommunications company, in 2019 conducted a live trial of its 5G network with support from China's Huawei.", "The company said it expects to begin rolling out 5G services in Cambodia by the end of 2019.GSMA predicted that by 2025, Cambodia will have approximately 24.3 million total mobile connections with smartphone connections up to 69%.", "The market is predicted to adopt 1.6 million of 5G connections within 5 years from 2020.Though so, it's believed that 4G still have room for growth and will continue to be the majority network connection.The government state communications corporation is Telecom Cambodia, founded in 2006 as an expansion of the telecom operating department of the Ministry of Posts and Telecommunications.===Mobile networks=== Network Company NotesSmartSmart Axiata Co., Ltd* Incorporates the former Hello Axiata and Star-Cell* MobitelCamGSM Co., Ltd.* Also known as Cellcard* Incorporates the former Mfone* CooTelXinwei (Cambodia) Telecom Co., Ltd* SEATELSoutheast Asia Telecom (Cambodia) Co., Ltd.*Incorporates the former GT-TEL* MetfoneViettel (Cambodia) Pte., Ltd.* Incorporates the former Beeline* qbCambodia Advance Communications Co., Ltd. (CADCOMMS)*" ], [ "Radio and television", "As of 2019, Cambodian broadcasters were a mixture of state-owned, joint public-private, and privately owned companies.===Radio stations===As of 2019, there were roughly 84 radio broadcast stations: 1 state-owned broadcaster with multiple stations and a large mixture of public and private broadcasters.", "Several international broadcasters are also available.====Phnom Penh====* Apsara Radio FM 97* Angel Radio 96.3Mhz Kampot* BBC World Service 100.0 MHz* Dance Radio 96.6Mhz * DAP Radio FM 93.75* Family FM 99.5* Hang Meas Radio FM 104.5* Koh Santepheap Daily FM 87.75* National Radio Kampuchea* Phnom Penh Radio FM 103* Radio FM 90.5* Radio Beehive FM 105* DaunPenh eFM 87.50Mhz* ABC News FM 107.5* Lotus Radio FM 100.5hz* Radio Free Asia* Radio Khmer FM 107* Radio Love FM 97.5* Radio Town FM 102.3 MHz* Raksmey Hang Meas Radio FM 95.7000* Royal Cambodia Armed Forces Radio FM 98* Voice of America Khmer* Women's Media Centre of Cambodia (WMC) Radio FM 102====Provincial stations====There are radio stations in each of the following provinces: Banteay Meanchey, Battambang, Kampong Cham, Kampong Thom, Kampot, Kandal, Pailin, Preah Vihear, Siem Reap, Sihanoukville and Svay Rieng.===Television===Cambodia has 27 TV broadcast stations with most operating on multiple channels, including 1 state-operated station broadcasting from multiple locations, 11 stations either jointly operated or privately owned with some broadcasting from several locations.", "Multi-channel cable and satellite systems are also available.", "There is one Chinese joint venture television station with the Ministry of Interior.", "Several television and radio operators broadcast online only (often via Facebook).====Broadcast and cable networks====* PNN TV* Apsara Television (TV11)* Bayon Television* Bayon News Television* Cambodia Cable Television (CCTV)* Cambodian News Channel (CNC)* Cambodian Television Network (CTN)* CTV 8 HD* Hang Meas HDTV* Khmer Television 9 HDTV (TV9 HDTV)* My TV* National Television of Cambodia (TVK)* One TV (Royal Media Entertainment Corporation, LTD)* Phnom Penh Municipal Cable Television (PPCTV Co., LTD)* Phnom Penh Television (TV3)* TV5 Cambodia* One News====Provincial television stations====* Kandal Province - Broadcasting on channel 27, Bayon Television is Cambodia's only UHF channel.", "A private television company belonging to Prime Minister Hun Sen, it also operates Bayon Radio FM 95 MHz.", "It was established in January 1998.", "* Mondulkiri - Established in 1999, relays TVK on channel 10.", "* Preah Vihear - Established in 2006, broadcasts on channel 7.", "* Ratanakiri - Established in 1993, relays TVK on channel 7.", "* Siem Reap - Established in 2002, relays TV3 on channel 12.===Most viewed channels=== Position Channel Share of total viewing (%) 1 Hang Meas 22.1 2 CTN 18.3 3 MyTV 10.5 4 PNN TV 8.1 5 TV5 4.4 6 Bayon TV 2.6 7 CTV 8 2.0 8 SEATV 1.4 9 TV9 1.2 10 TV11 1.0 11 TV3 0.9 12 CNC 0.8 13 ETV 0.6 14 TVK 0.4" ], [ "Internet", " the number of internet users in Cambodia rose to 15.8 million, about 98.5% of the population.", "According to the Telecommunications Regulator of Cambodia (TRC), the number of registered SIM cards rose by 9.4 percent during the first half of the year, reaching 20.8 million.", "The SIM card market is saturated, with Cambodia now having more active SIM cards than people.", "According to TRC, there are six telecommunications firms in the country: Cellcard, Smart Axiata, Metfone, Seatel, Cootel, and qb.", "Three companies, Metfone, Cellcard, and Smart, account for 90% of users.", "TRC noted that, as of February 2019, Facebook had seven million users in Cambodia.List of Internet service providers* AngkorNet* AZ (Online)* Cambo Technology (ISP) Co., Ltd.* Cambodia Internet Corp* Cambotech* Camintel* Camnet (Telecom Cambodia)* CB (Cambodian Broadband)* CDC* Cellcard (Mobitel)* CooTel* Chuan Wei * CIDC IT* Citylink* Digi ISP* Dragon Royal Telecom* EmCom* Everyday* Ezecom* GTD* Hiway Telecom* Home Internet* Kingtel Communications Limited* MaxBIT* MekongNet (Angkor Data Communication Group)* Metfone* Mobilastic* Neocom ISP (NTC)* NTC - NeocomISP Limited* Open Net* PCP* PP Net Phone* PPCTV Broadband Internet Service* SingMeng Telemedia* yes SEATEL Cambodia* SINET (S.I Group Co., Ltd)* Smart @Home* TeleSURF* Telecom Cambodia* TODAY ISP (Today Communication Co., Ltd)* Turbotech* Vimean Seile* Wicam* WIP* Wireless Internet Provider* WirelessIP* Y5Net (BDKTel Co,LTD)* Mekong CLOUD Cambodia===Internet censorship and surveillance===In its ''Freedom on the Net 2013'' report, Freedom House gives Cambodia a \"Freedom on the Net Status\" of \"partly free\".Compared to traditional media in Cambodia, new media, including online news, social networks and personal blogs, enjoy more freedom and independence from government censorship and restrictions.", "However, the government does proactively block blogs and websites, either on moral grounds, or for hosting content deemed critical of the government.", "The government restricts access to sexually explicit content, but does not systematically censor online political discourse.", "Since 2011 three blogs hosted overseas have been blocked for perceived antigovernment content.", "In 2012, government ministries threatened to shutter internet cafes too near schools—citing moral concerns—and instituted surveillance of cafe premises and cell phone subscribers as a security measure.Early in 2011, very likely at the urging of the Ministry of Posts and Telecommunications, all Cambodian ISPs blocked the hosting service Blogspot, apparently in reaction to a December 2010 post on KI-Media, a blog run by Cambodians from both inside and outside the country.", "The site, which is often critical of the administration, described the prime minister and other officials as \"traitors\" after opposition leader Sam Rainsy alleged they had sold land to Vietnam at a contested national border.", "All ISPs but one subsequently restored service to the sites following customer complaints.", "In February 2011, however, multiple ISPs reinstated blocks on individual Blogspot sites, including KI-Media, Khmerization—another critical citizen journalist blog—and a blog by the Khmer political cartoonist Sacrava.There are no government restrictions on access to the Internet or credible reports that the government monitors e-mail or Internet chat rooms without appropriate legal authority.", "During 2012 NGOs expressed concern about potential online restrictions.", "In February and November, the government published two circulars, which, if implemented fully, would require Internet cafes to install surveillance cameras and restrict operations within major urban centers.", "Activists also reported concern about a draft “cybercrimes” law, noting that it could be used to restrict online freedoms.", "The government maintained it would only regulate criminal activity.The constitution provides for freedom of speech and press; however, these rights were not always respected in practice.", "The 1995 press law prohibits prepublication censorship or imprisonment for expressing opinions; however, the government uses the penal code to prosecute citizens on defamation, disinformation, and incitement charges.", "The penal code does not prescribe imprisonment for defamation, but does for incitement or spreading disinformation, which carry prison sentences of up to three years.", "Judges also can order fines, which may lead to jail time if not paid.", "The constitution requires that free speech not adversely affect public security.The constitution declares that the king is “inviolable,” and a Ministry of Interior directive conforming to the defamation law reiterates these limits and prohibits publishers and editors from disseminating stories that insult or defame government leaders and institutions.", "The continued criminalization of defamation and disinformation and a broad interpretation of criminal incitement constrains freedom of expression.The law provides for the privacy of residence and correspondence and prohibits illegal searches; however, NGOs report that police routinely conduct searches and seizures without warrants.Corruption remains pervasive and governmental human rights bodies are generally ineffective.", "A weak judiciary that sometimes fails to provide due process or fair trial procedures is a serious problem.", "The courts lack human and financial resources and, as a result, are not truly independent and are subject to corruption and political influence.On 17 February 2021, the Cambodian government announced its plans to launch a censorship scheme called \"National Internet Gateway\" which heavily resembles China's Great Firewall, and it will get launched in February 2022." ], [ "See also", "* Media of Cambodia* Ministry of Posts and Telecommunications (Cambodia)" ], [ "References" ], [ "External links", "* Networks: Cambodia * Ministry of Posts and Telecommunications * Telecom Cambodia* Television stations in Cambodia* \"3G phones banned in anti-porn drive\", China Daily (Associated Press), 26 May 2006.Retrieved 24 October 2013." ] ]

[ [ "Transport in Cambodia" ], [ "Introduction", "A national transport map of CambodiaKien Svay, Kandal ProvinceA rural road in CambodiaThe system of '''transport in Cambodia''', rudimentary at the best of times, was severely damaged in the chaos that engulfed the nation in the latter half of the 20th century.", "The country's weak transport infrastructure hindered emergency relief efforts, exacerbating the logistical issues of procurement of supplies in general and their distribution.", "Cambodia received Soviet technical assistance and equipment to support the maintenance of the transportation network." ], [ "Road transport", "Battambang=== Highway network ===* Total - 38,257 km (2004)** Paved - 2,406 km (2004)** Unpaved - 35,851 km (2004)Of the current total roadway network, only about 50% of the roads and highways are hard surfaced, all-weather, and in good condition.", "About 50% of the roads were constructed of crushed stone, gravel, or compacted earth.", "Secondary roads are of unimproved earth or were little more than tracks.", "In 1981 Cambodia opened a newly repaired section of National Route 1 which runs southeast from Phnom Penh to the Vietnamese border.", "The road, which suffered damage during the war years, was restored most probably by Vietnamese army engineers.In the late-1980s, Cambodia's road network was both underutilized and unable to meet even the modest demands placed upon it by a preindustrial agrarian society.", "Commercial vehicles, such as trucks and buses, were insufficient in number and lacked the spare parts necessary to keep them running.", "Road construction and maintenance were ignored by a financially hard-pressed governments, while insurgents regularly destroyed bridges and rendered some routes unsafe for travel.Cambodia is upgrading the main highways to international standards and most are vastly improved from 2006.Most main roads are now paved.", "And now road construction is on going from the Thailand border at Poipet to Siem Reap (Angkor Wat).", "Funded by over $3 billion of Chinese loans, Chinese companies have built of roads as well as several major bridges.An expressway network is being developed, the 190km Phnom Penh-Sikhanoukville expressway (E4) opened in October 2022, the construction to Bavet started in June 2023.Chart of 01/2014 National Highway Code Approx length Origin Terminus'''National Highway 1''' 10001 Phnom Penh Bavet - Vietnam Border '''National Highway 2''' 10002 Phnom Penh Phnom Den - Vietnam Border '''National Highway 3''' 10003 Phnom Penh Kampot - Veal Renh (NH4) '''National Highway 4''' 10004 Phnom Penh Sihanoukville '''National Highway 5''' 10005 Phnom Penh Battambang - Poipet - Thai Border '''National Highway 6A''' 10006A Phnom Penh Skuon '''National Highway 6''' 10006 Skuon Siem Reap - Sisophon (NH5) '''National Highway 7''' 10007 Skuon Stung Treng - Laos Border '''National Highway 8''' 10008 NH6A - Prek Tamak Bridge to NH7 near the Vietnam Border.=== Other transport ===Motorcycles are by far the most common transport medium in Cambodia.", "\"Cyclo\" (as hand-me-down French) or cycle rickshaws were popular in the 1990s but are increasingly replaced by ''remorques'' (carriages attached to motorcycles) and rickshaws imported from India.", "Cyclos are unique to Cambodia in that the cyclist sits behind the passenger(s) seat, as opposed to cycle rickshaws in neighbouring countries where the cyclist is at the front and pulls the carriage.", "With 78% mobile phone penetration rate, ride-hailing apps have become popular in recent years.", "The first locally owned ride-hailing app, ExNet taxi app, was launched in 2016, after which another locally developed PassApp taxi was also introduced.", "The ExNet and PassApp use the same technology and architect for their application, except that ExNet is a taxi-based ride-hailing service while PassApp is more of rickshaw-based one.", "Uber and Grab joined the market in 2017.The entry and later merger of Uber and Grab did not negatively affect the local apps as the locals have the first-mover advantage and could secure a large number of patrons.", "As of today, PassApp is seen as an able competitor for the Singapore-based Grab in the Cambodian transport market.", "Thai Duong Bus CambodiaAside from the private-hire vehicles and ride-hailing service, public transport is also available but only in the capital.", "Phnom Penh city bus service started in 2015 with only three routes under the assistance of JICA.", "Today, Phnom Penh City Bus operates 13 routes." ], [ "Railways", "Two rail lines exist, both originating in Phnom Penh and totaling about 612 kilometers of 1,000 mm (3 ft 3 3⁄8 in) metre gauge single track.", "The first line or the northern line, built by The French colonial government, running from Phnom Penh to Poipet on the Thai border, between 1930 and 1940, with Phnom Penh Railway Station opening in 1932.The final connection with Thailand was completed by Royal State Railways in 1942.The service from Bangkok to Battambang was suspended when the French Indochinese Government resumed sovereignty over Battambang and the Sisophon area from Thailand on 17 December 1946, as Thailand was seen as a supporter of Khmer Issarak, the anti-French, Khmer nationalist political movement.", "A third line is planned to connect Phnom Penh with Vietnam, the last missing link of the planned rail corridor between Singapore and the city of Kunming, China.", "A new north–south line is also planned.", "The lines from Phnom Penh to Sisophon and from Sisophon to Poipet have been rehabilitated; starting with Poipet to Srey Sisophon in April 2018 and Sisophon to Phnom Penh in early July (2018).", "The active part, the southern line, of the network is the Phnom Penh-Sihanoukville line, with stops at Takeo and Kampot.", "The first line to be re-opened in Cambodia was the 118 km long route from Phnom Penh to Touk Meas and the complete southern line in May 2011 (or Toll Royal Railway).", "Toll Royal Railway (Cambodia) had been given a 30-year concession from The Royal Government of Cambodia to operate Cambodia's railway network.===Routes===Phnom Penh - Pursat - Moung Ruessei - Battambang - Sisophon - PoipetPhnom Penh - Takeo - Touk Meas - Damnak Chang'aeur - Veal Renh - Sihanoukville" ], [ "Waterways", "The nation's extensive inland waterways were important historically in domestic trade.", "The Mekong and the Tonlé Sap Rivers, their numerous tributaries, and the Tonlé Sap provided avenues of considerable length, including 3,700 kilometers navigable all year by craft drawing 0.6 meters and another 282 kilometers navigable to craft drawing 1.8 meters.", "In some areas, especially west of the Mekong River and north of the Tonle Sap River, the villages were completely dependent on waterways for communications.", "Launches, junks, or barges transport passengers, rice, and other food in the absence of roads and railways.According to the Ministry of Communications, Transport, and Post, Cambodia's main ferry services crossing the Bassac River and the middle Mekong River were restored in 1985.The major Mekong River navigation routes also were cleared for traffic.", "Seaplane service to all waterways and islands in now offered by Aero Cambodia Airline.===Seaports and harbors===A ferry crossing the Mekong to Neak Leung townCambodia has two major ports, Phnom Penh Autonomous Port and Sihanoukville Autonomous Port, also known as ''Kampong Som'', and five minor ports.", "Phnom Penh, at the junction of the Bassac, the Mekong, and the Tonle Sap Rivers, is the only river port capable of receiving 8,000-ton ships during the wet season and 5,000-ton ships during the dry season.", "In 2018 the port received 205,000 TEUs totalling 2.9 million tonnes.", "Its 2018 profits were US$7.35 million, up 36% from 2017.Sihanoukville port reopened in late-1979.It had been built in 1960 with French assistance.", "In 1980 some 180 Soviet dockworkers, having brought with them forklifts and trucks, were reportedly working at ''Kampong Som'' as longshoremen or as instructors of unskilled Cambodian port workers.", "By 1984 approximately 1,500 Cambodian port workers were handling 2,500 tons of cargo per day.", "According to official statistics, Sihanoukville had handled only 769,500 tons in the four prior years (1979 to 1983), a level that contrasted sharply with the port's peacetime capacity of about one million tons of cargo per year.====Merchant marine====* Total: 626 ships ( or over) totaling /* Ships by type: bulk carrier 41, cargo ship 533, chemical tanker 10, container ship 8, passenger ship/cargo 6, petroleum tanker 11, refrigerated cargo 15, roll-on/roll-off 1, vehicle carrier 1 (2008)* Note: 467 foreign-owned: Canada 2, China 193, Cyprus 7, Egypt 13, Gabon 1, Greece 3, Hong Kong 8, Indonesia 22, Japan 1, South Korea 22, Latvia 1, Lebanon 8, Netherlands 1, Romania 1, Russia 83, Singapore 4, Syria 48, Taiwan 1, Turkey 26, Ukraine 34, UAE 34, United States 6 (2008)" ], [ "Airports", "Siem Reap International AirportThe country possesses twenty-six airfields, of which only thirteen were usable in the mid-1980s.", "Eight airfields had permanent-surface runways.", "Phnom Penh International Airport in Phnom Penh is the largest airport; it also serves as the main base for the renascent Cambodian Air Force.Cambodia's second largest airport is Angkor International Airport in the tourist city of Siem Reap.", "Tourist traffic into Angkor International Airport saw passenger numbers overtake those of Phnom Penh in 2006, the airport now being the country's busiest.Cambodia also opened a new Soviet-built airfield at Ream, Sihanoukville International Airport in late-1983, which never saw commercial air traffic until January 2007.There are additional airports in Battambang and Stung Treng.The new national airline Cambodia Angkor Air was launched in 2009, with an investment from Vietnam Airlines.", "Aero Cambodia Airline started business in 2011 offering flights to all airports and waterways with seaplanes.Techo Takhmao International Airport, intended to replace the existing Phnom Penh International Airport as the city's main airport, currently under construction in Kandal, Cambodia.", "Located about 30–40 kilometres (16–22 NM; 19–25 mi) south of Phnom Penh, it is expected to open in 2023 and be fully operational by 2025.===Airports with paved runways===* Total: 6 (2010)** 2,500 to 3,000 m: 3** 1,500 to 2,500 m: 2** 1,000 to 1,500 m: 1===Airports with unpaved runways===*Total: 11 (2010)** 1,500 to 2,500 m: 1** 1,000 to 1,500 m: 9** under 1,000 m: 1===Heliports===* 1 (2010)" ], [ "See also", "*State Secretariat of Civil Aviation*Ministry of Public Works and Transport, of Cambodia*Transport in Phnom Penh*Phnom Penh International Airport" ], [ "References" ], [ "External links", "* The SihanoukVille Port* Cambodians ride 'bamboo railway' * Video, photos and travel diary of Cambodia's trains by traveller Tom Grundy.", "* The Sihanoukville Airport* Thai Duong bus in Cambodia * National highways* Inland waterways in Cambodia* Buses in Cambodia* SihanoukVille Train Station" ] ]

[ [ "Foreign relations of Cambodia" ], [ "Introduction", "The Cambodian government has diplomatic relations with most countries, including the United States, the United Kingdom, and France, as well as all of its Asian neighbors, including China, India, Vietnam, Laos, South Korea, and Thailand.", "The government is a member of most major international organizations, including the United Nations and its specialized agencies such as the World Bank and International Monetary Fund.", "The government is an Asian Development Bank (ADB) member, a member of ASEAN, and of the WTO.", "In 2005 Cambodia attended the inaugural East Asia Summit.", "The government is also a member of the Pacific Alliance (as observer) and Shanghai Cooperation Organisation (as dialogue partner)." ], [ "International disputes", "Delegates of the ASEAN Summit pose for a photograph at the Peace Palace in Phnom Penh, Cambodia, on 19 November 2012.Cambodia is involved in a dispute regarding offshore islands and sections of the boundary with Vietnam.", "In addition, the maritime boundary Cambodia has with Vietnam is undefined.", "Parts of Cambodia's border with Thailand are indefinite, and the maritime boundary with Thailand is not clearly defined." ], [ "Illicit drugs", "Cambodia is a transshipment site for Golden Triangle heroin, and possibly a site of money laundering.", "There is corruption related to narcotics in parts of the government, military and police.", "Cambodia is also a possible site of small-scale opium, heroin, and amphetamine production.", "The country is a large producer of cannabis for the international market." ], [ "International organization participation", "ACCT, AsDB, ASEAN, ESCAP, FAO, G-77, IAEA, IBRD, ICAO, ICC, ICRM, IDA, IFAD, IFC, IFRCS, ILO, IMF, IMO, Intelsat (nonsignatory user), International Monetary Fund, Interpol, IOC, ISO (subscriber), ITU, NAM, OPCW, PCA, UN, UNCTAD, UNESCO, UNIDO, UPU, WB, WFTU, WHO, WIPO, WMO, WTO, WToO, WTrO (applicant)" ], [ "Diplomatic relations", "List of countries which Cambodia maintains diplomatic relations with:425x425px#CountryDate111 July 1950219 December 1950327 July 1951416 November 1951516 November 1951615 January 1952715 May 1952828 May 1952928 May 19521030 May 1952114 November 1952121953131953144 May 19541512 July 19551615 June 1956176 November 19561816 April 19571927 August 19572016 April 1957212219 July 19582313 February 19592416 February 19592518 February 19592615 April 19602718 September 19602830 November 19602926 April 19613010 January 19633113 July 19633922 July 19633219 February 19643320 December 1964341 February 19663519663624 June 1967379 October 1967389 October 1967399 October 1967409 October 19674119 October 19674219 March 196843May 1970445 October 19724513 October 1972461 August 197347September 19744818 April 1975495 September 19755026 September 1975514 December 19755231 May 19765354Before 198255Before 198356Before 198457Before 198458March 1984591980s—1980s6016 February 19906127 April 19916225 November 19916313 December 1991–17 December 19916419 December 1991659 March 19926623 April 19926723 May 19926829 May 1992695 June 1992709 June 19927117 February 1993726 June 19937316 February 19947425 February 19947510 March 19947625 March 1994–25 March 19947726 April 19947829 April 19947915 May 19948014 June 19948118 June 19948229 June 19948316 July 19948429 September 1994857 October 19948621 October 19948727 October 1994881 November 19948917 November 1994902 December 1994915 January 19959223 January 19959326 January 1995942 February 19959522 February 1995968 March 19959710 March 19959823 March 1995996 April 199510012 April 19951012 May 199510218 May 199510324 May 199510418 August 19951057 September 199510621 September 199510722 September 199510822 September 199510926 September 199511025 October 199511129 November 199511215 February 199611326 February 199611426 February 19961158 April 19961168 May 199611716 July 199611815 August 199611910 September 199612023 October 199612129 October 199612220 February 199712325 March 199712414 October 199912530 October 1999126Before 199912716 August 200012813 September 200012928 May 200113030 June 200113115 May 200213229 July 200213319 June 200313423 December 200313531 August 200513629 September 20051378 March 200613825 April 20071391 April 20081409 April 200814113 November 20081422 March 200914329 June 20091444 July 200914512 October 200914626 October 200914716 November 200914812 January 201014912 January 201015016 January 201015118 January 20101522 February 20101539 February 201015422 February 201015527 April 201015628 April 201015728 April 201015818 May 201015927 May 201016025 June 201016130 June 201016230 June 20101632 July 20101646 August 20101657 October 201016625 October 201016712 April 20111688 June 201116928 June 201117020 July 201117122 July 201117231 October 201117322 February 201217428 April 201617520 January 201717616 November 201817711 July 201917811 November 201917923 January 2020180Unknown" ], [ "Bilateral relations", "===Africa======Americas=== Country Formal relations began inNotes25 November 1991See Cambodia–Canada relations* Cambodia is accredited to Canada from its Permanent Mission to the United Nations in New York City.", "* Canada is accredited to Cambodia from its embassy in Bangkok, Thailand.September 1976* Cambodia is accredited to Mexico from its embassy in Washington, D.C., United States.", "* Mexico is accredited to Cambodia from its embassy in Hanoi, Vietnam.11 July 1950See Cambodia–United States relations* Cambodia has an embassy in Washington, D.C.* United States has an embassy in Phnom Penh.===Asia=== Country Formal relations beganNotes9 June 1992See Brunei–Cambodia relations* Brunei has an embassy in Phnom Penh.", "* Cambodia has an embassy in Bandar Seri Begawan.", "* The relations are mainly on economics and security.", "(PRC)19 July 1958See Cambodia–China relations* Cambodia and the People's Republic of China relations have strengthened considerably after the end of the Cambodian-Vietnamese War.", "* Cambodia has an embassy in Beijing.", "* China has an embassy in Phnom Penh China (ROC, Taiwan)No official relations* Relations between Cambodia and the Republic of China on Taiwan are non-existent under the One China policy, though the ROC had relations with the U.S.-backed Khmer Republic during the Cambodian Civil War.", "* Cambodia is represented by the Taipei Economic and Cultural Office in Ho Chi Minh City.1981See Cambodia–India relations* Cambodia and India have ties that go deep into history, in areas of religion, architecture, art, political systems and royal families.", "* India has an embassy in Phnom Penh.", "* Cambodia has an embassy in New Delhi.1957See Cambodia–Indonesia relations* The relations between both countries dates back to the Pre-Angkorian and Srivijaya era.19601993 (reestablished)See Cambodia–Israel relations* Israel has an embassy in Bangkok.1950See Cambodia–Japan relations* Japan has an embassy in Phnom Penh.", "* Both Countries relations that in 1946, King Norodom Sihanouk said that Japan do not need to pay for the destruction since 1940, he said Cambodia wanted to be allied with Japan.15 June 1956* Laos has an embassy in Phnom Penh.", "* Cambodia has an embassy in Vientiane.", "* Historically, relations have been tense, with long-standing unresolved border disputes.2 December 1996See Cambodia–Malaysia relations* The relations are mainly in economic.", "* Malaysia was the fourth largest foreign investors to Cambodian in 2009.28 December 1964 See Cambodia–North Korea relationsSee Cambodia–Pakistan relations* Cambodia is accredited to Pakistan from its embassy in New Delhi, India.", "* Pakistan has an embassy in Phnom Penh.1956See Cambodia–Philippines relationsPhilippine President Rodrigo Duterte with King Norodom Sihamoni at the Royal Palace in Phnom Penh on 14 December 2016.", "* The two countries have an agreements on economic and trade relations, agricultural and agribusiness collaboration, and tourism cooperation.", "* Cambodia has an embassy in Manila.", "* Philippines has an embassy in Phnom Penh.10 August 1965See Cambodia–Singapore relations* Cambodia was one of the first countries to recognize Singapore's sovereignty when it became independent in 1965.", "* Prime Minister Lee Hsien Loong visited Cambodia in 2005 and 2012.", "* Singapore has an embassy in Phnom Penh.", "* Cambodia has an embassy in Singapore.18 May 1970King Norodom Sihamoni granting an audience to President of South Korea Lee Myung-bak in 2009.", "* Cambodia has an embassy in Seoul.", "* South Korea has an embassy in Phnom Penh.See Cambodia–South Korea relations1956*Cambodia embassy in Ankara, Turkey is presented for Tajikistan.", "See Cambodia–Thailand relations* Cambodian–Thai border dispute* The Kingdom of Thailand has an embassy in Phnom Penh.", "* The Kingdom of Cambodia has an embassy in Bangkok.", "* Thailand was once Cambodia's arch-enemy.", "1959See Cambodia–Turkey relations* Cambodia has an embassy in Ankara.", "* Turkey has an embassy in Phnom Penh.", "*Trade volume between the two countries was US$108.4 million in 2015 (Cambodian exports/imports: 94.7/13.7 million USD).", "See Cambodia–Vietnam relations* Bilateral relations between the Cambodia and Vietnam were for long strained due to the Cambodian-Vietnamese War.", "* The maritime boundary with Vietnam is hampered by unresolved dispute over sovereignty of offshore islands.", "* Cambodia has an embassy in Hanoi.", "* Vietnam has an embassy in Phnom Penh.===Europe=== Country Formal relations beganNotes 9 October 1967See Cambodia–Denmark relations* Cambodia is accredited to Denmark from its embassy in London, United Kingdom.", "* Denmark is accredited to Cambodia from its embassy in Bangkok, Thailand.20 January 1970*Finland recognized Cambodia on 19 December 1969.Diplomatic relations established on 20 January 1970, re-established 9 August 1976.", "*Cambodia is represented in Finland through its embassy in London, England*Finland is represented in Cambodia through its embassy in Bangkok, Thailand1863See Cambodia–France relations* French president Charles de Gaulle visited Cambodia in 1966 and was given a welcome by Prince Norodom Sihanouk.", "* Cambodia has an embassy in Paris.", "* France has an embassy in Phnom Penh.See Cambodia–Germany relations*Cambodia has an embassy in Berlin.", "* Germany has an embassy in Phnom Penh.", "* Cambodia's embassy in Brussels, Belgium is also accredited to Greece* Greece's embassy in Bangkok is also accredited to Cambodia.", "* Both countries are full members of the Francophonie.10 July 1995*Cambodia is accredited to Hungary from its Embassy in Berlin, Germany.", "*Hungary open its Embassy in Phnom Penh.29 March 1992*Poland closed its embassy in Phnom Penh at 2009 and accredited from Bangkok, Thailand.", "*Cambodia is accredited to Poland from its embassy in Berlin, Germany.16 November 1951See Cambodia–Spain relations* Cambodia is accredited to Spain from its embassy in Paris, France.", "* Spain is accredited to Cambodia from its embassy in Bangkok, Thailand.1957*Switzerland recognized Cambodia in 1957, and the two countries have maintained diplomatic relations since 1963.", "*Bilateral relations between Cambodia and Switzerland are good.", "Switzerland supports the transition process and development efforts in Cambodia.", "*Trade between the two countries is marginal.23 April 1992See Cambodia–Ukraine relations1953 1976 (reestablished)See Cambodia–United Kingdom relations* British Minister of State Hugo Swire visited Cambodia on 29 January 2014 to discuss solutions for political deadlock with the ruling and opposition parties.", "* Cambodia has an embassy in London.", "* United Kingdom has an embassy in Phnom Penh.===Oceania=== Country Formal relations beganNotes1950'sSee Australia–Cambodia relations* Australia has an embassy in Phnom Penh.", "* Cambodia has an embassy in Canberra." ], [ "Country with no relations", "There are 17 countries that haven't establish any diplomatic relations with Cambodia:************" ], [ "See also", "*List of diplomatic missions in Cambodia*List of diplomatic missions of Cambodia" ], [ "References" ], [ "Further reading", "* Deth, Sok Udom, and Serkan Bulut, eds.", "''Cambodia's Foreign Relations in Regional and Global Contexts'' (Konrad-Adenauer-Stiftung, 2017; comprehensive coverage) full book online free.", "** Path Kosal, \"Introduction: Cambodia's Political History and Foreign Relations, 1945-1998\" pp 1–26 * Acharya, Amitav.", "''The Making of Southeast Asia: International Relations of A Region'' (Cornell UP, 2012)* Chandler, David.", "''The Tragedy of Cambodian History: Politics, War, and Revolution since 1945'' (Yale UP, 1991)* Ciorciari, John D. \"Cambodia in 2019: Backing Further into a Corner.\"", "''Asian Survey'' 60.1 (2020): 125–131.online* Clymer, Kenton.", "''Troubled Relations: The United States and Cambodia since 1870'' (Northern Illinois UP, 2007).", "* Leighton, Marian Kirsch.", "\"Perspectives on the Vietnam-Cambodia border conflict.\"", "''Asian Survey'' 18.5 (1978): 448–457.online* Leng, Thearith.", "\"2016: A Promising Year for Cambodia?.\"", "''Southeast Asian Affairs'' (2017): 133–146.online* Morris, Stephen J.", "''Why Vietnam invaded Cambodia: Political culture and the causes of war'' (Stanford University Press, 1999).", "* Peou, Sorpong.", "\"Cambodia in 2018: a year of setbacks and successes.\"", "''Southeast Asian Affairs'' 2019.1 (2019): 104–119.online* Richardson, Sophie.", "''China, Cambodia and the Five Principles of Peaceful Coexistence'' (Columbia UP, 2010)* Smith, Roger.", "''Cambodia's Foreign Policy'' (Cornell UP, 1965).", "* Un, Kheang, and Jing Jing Luo.", "\"Cambodia in 2019: Entrenching One-Party Rule and Asserting National Sovereignty in the Era of Shifting Global Geopolitics.\"", "''Southeast Asian Affairs'' 2020.1 (2020): 117–134.online* Westad, Odd Arne, and Sophie Quinn-Judge, eds.", "''The third Indochina war: conflict between China, Vietnam and Cambodia, 1972-79'' (Routledge, 2006).", "* Womack, Brantly.", "\"Asymmetry and systemic misperception: China, Vietnam and Cambodia during the 1970s.\"", "''Journal of Strategic Studies'' 26.2 (2003): 92-119 online." ], [ "External links", "* Ministry of Foreign Affairs and International Cooperation* US Department of State: Foreign relations with Southeast Asia 1961–63* Foreign relations between Cambodia and Germany* Japan-Cambodia Relations* List of foreign embassies in Cambodia* Foreign relations between Cambodia and Australia* AsiaSociety: essays relating to the development of Cambodia" ] ]

[ [ "Khmer architecture" ], [ "Introduction", "The 12th-century temple of Angkor Wat is the masterpiece of Angkorian architecture.", "Constructed under the direction of the Khmer king Suryavarman II, Angkor Wat is a Hindu-Buddhist temple.", "'''Khmer architecture''' (), also known as '''Angkorian architecture''' (), is the architecture produced by the Khmers during the Angkor period of the Khmer Empire from approximately the later half of the 8th century CE to the first half of the 15th century CE.The architecture of the Indian rock-cut temples, particularly in sculpture, had an influence on Southeast Asia and was widely adopted into the Indianised architecture of Cambodian (Khmer), Annamese and Javanese temples (of the Greater India).", "Evolved from Indian influences, Khmer architecture became clearly distinct from that of the Indian sub-continent as it developed its own special characteristics, some of which were created independently and others of which were incorporated from neighboring cultural traditions, resulting in a new artistic style in Asian architecture unique to the Angkorian tradition.", "The development of Khmer architecture as a distinct style is particularly evident in artistic depictions of divine and royal figures with facial features representative of the local Khmer population, including rounder faces, broader brows, and other physical characteristics.", "In any study of Angkorian architecture, the emphasis is necessarily on religious architecture, since all the remaining Angkorian buildings are religious in nature.", "During the period of Angkor, only temples and other religious buildings were constructed of stone.Non-religious buildings such as dwellings were constructed of perishable materials such as wood, and so have not survived.", "The religious architecture of Angkor has characteristic structures, elements, and motifs, which are identified in the glossary below.", "Since a number of different architectural styles succeeded one another during the Angkorean period, not all of these features were equally in evidence throughout the period.", "Indeed, scholars have referred to the presence or absence of such features as one source of evidence for dating the remains." ], [ "Periodization", "Many temples had been built before Cambodia became the powerful Khmer Empire which dominated a large part of mainland Southeast Asia.", "At that time, Cambodia was known as the Chenla kingdom, the predecessor state of the Khmer empire.Latest research reveals that the Khmer already erected stone buildings in the protohistoric period, which they used for the worship of mighty tutelary spirits.", "This earliest extant architecture consists of relatively small cells made from prefabricated megalithic construction parts, which probably date at least to the second century BC.There are three pre-Angkorean architectural styles:* Sambor Prei Kuk style (610–650): Sambor Prei Kuk, also known as Isanapura, was the capital of the Chenla Kingdom.", "Temples of Sambor Prei Kuk were built in rounded, plain colonettes with capitals that include a bulb.", "* Prei Khmeng style (635–700): structures reveal masterpieces of sculpture but examples are scarce.", "Colonettes are larger than those of previous styles.", "Buildings were more heavily decorated but had general decline in standards.", "* Kompong Preah style (700–800): temples with more decorative rings on colonettes which remain cylindrical.", "Brick constructions were being continued.Scholars have worked to develop a periodization of Angkorean architectural styles.", "The following periods and styles may be distinguished.", "Each is named for a particular temple regarded as paradigmatic for the style.", "* Kulen style (825–875): continuation of pre-Angkorean style but it was a period of innovation and borrowing such as from Cham temples.", "Tower is mainly square and relatively high as well as brick with laterite walls and stone door surrounds but square and octagonal colonettes begin to appear.", "* Preah Ko style (877–886): Hariharalaya was the first capital city of the Khmer empire located in the area of Angkor; its ruins are in the area now called Roluos some fifteen kilometers southeast of the modern city of Siem Reap.", "The earliest surviving temple of Hariharalaya is Preah Ko; the others are Bakong and Lolei.", "The temples of the Preah Ko style are known for their small brick towers and for the great beauty and delicacy of their lintels.", "* Bakheng Style (889–923): Bakheng was the first temple mountain constructed in the area of Angkor proper north of Siem Reap.", "It was the state temple of King Yasovarman, who built his capital of Yasodharapura around it.", "Located on a hill (phnom), it is currently one of the most endangered of the monuments, having become a favorite perch for tourists eager to witness a glorious sundown at Angkor.", "* Koh Ker Style (921–944): during the reign of King Jayavarman IV, capital of Khmer empire was removed from Angkor region through the north which is called Koh Ker.", "The architectural style of temples in Koh Ker, scale of buildings diminishes toward center.", "Brick still main material but sandstone also used.", "* Pre Rup Style (944–968): under King Rajendravarman, the Angkorian Khmer built the temples of Pre Rup, East Mebon and Phimeanakas.", "Their common style is named after the state temple mountain of Pre Rup.", "* Banteay Srei Style (967–1000): Banteay Srei is the only major Angkorian temple constructed not by a monarch, but by a courtier.", "It is known for its small scale and the extreme refinement of its decorative carvings, including several famous narrative bas-reliefs dealing with scenes from Indian mythology.", "* Khleang Style (968–1010): the Khleang temples, first use of galleries.", "Cruciform gopuras.", "Octagonal colonettes.", "Restrained decorative carving.", "A few temples that were built in this style are Ta Keo, Phimeanakas.", "* Baphuon Style (1050–1080): Baphuon, the massive temple mountain of King Udayadityavarman II was apparently the temple that most impressed the Chinese traveller Zhou Daguan, who visited Angkor toward the end of the 13th century.", "Its unique relief carvings have a naive dynamic quality that contrast with the rigidity of the figures typical of some other periods.", "As of 2008, Baphuon is under restoration and cannot currently be appreciated in its full magnificence.", "* Classical or Angkor Wat Style (1080–1175): Angkor Wat, the temple and perhaps the mausoleum of King Suryavarman II, is the greatest of the Angkorian temples and defines what has come to be known as the classical style of Angkorian architecture.", "Other temples in this style are Banteay Samre and Thommanon in the area of Angkor, and Phimai in modern Thailand.", "* Bayon Style (1181–1243): in the final quarter of the 12th century, King Jayavarman VII freed the country of Angkor from occupation by an invasionary force from Champa.", "Thereafter, he began a massive program of monumental construction, paradigmatic for which was the state temple called the Bayon.", "The king's other foundations participated in the style of the Bayon, and included Ta Prohm, Preah Khan, Angkor Thom, and Banteay Chmar.", "Though grandiose in plan and elaborately decorated, the temples exhibit a hurriedness of construction that contrasts with the perfection of Angkor Wat.", "* Post Bayon Style (1243–1431): following the period of frantic construction under Jayavarman VII, Angkorian architecture entered the period of its decline.", "The 13th century Terrace of the Leper King is known for its dynamic relief sculptures of demon kings, dancers, and nāgas." ], [ "Materials", "Angkorian builders used brick, sandstone, laterite and wood as their materials.", "The ruins that remain are of brick, sandstone and laterite, the wood elements having been lost to decay and other destructive processes.Wooden structure depicted in a bas relief in Bayon===Brick===The earliest Angkorian temples were made mainly of brick.", "Good examples are the temple towers of Preah Ko, Lolei and Bakong at Hariharalaya, and Chóp Mạt in Tay Ninh.", "Decorations were usually carved into a stucco applied to the brick, rather than into the brick itself.", "This was because bricks were a softer material, and did not lend themselves to sculpting, as opposed to stones of different kinds such as the Sandstones or the Granites.", "However, the tenets of the Sacred Architecture as enunciated in the Vedas and the Shastras, require no adhesives to be used while building blocks are assembled one over the other to create the Temples, as such bricks have been used only in relatively smaller temples such as Lolei and The Preah Ko.", "Besides, strength of bricks is much lesser as compared to the stones (mentioned here-in) and the former degrade with age.Angkor's neighbor state of Champa was also the home to numerous brick temples that are similar in style to those of Angkor.", "The most extensive ruins are at Mỹ Sơn in Vietnam.", "A Cham story tells of the time that the two countries settled an armed conflict by means of a tower-building contest proposed by the Cham King Po Klaung Garai.", "While the Khmer built a standard brick tower, Po Klaung Garai directed his people to build an impressive replica of paper and wood.===Sandstone===The only stone used by Angkorian builders was sandstone, obtained from the Kulen mountains.", "Since its obtainment was considerably more expensive than that of brick, sandstone only gradually came into use, and at first was used for particular elements such as door frames.", "The 10th-century temple of Ta Keo is the first Angkorian temple to be constructed more or less entirely from Sandstone.===Laterite===Angkorian builders used laterite, a clay that is soft when taken from the ground but that hardens when exposed to the sun, for foundations and other hidden parts of buildings.", "Because the surface of laterite is uneven, it was not suitable for decorative carvings, unless first dressed with stucco.", "Laterite was more commonly used in the Khmer provinces than at Angkor itself.", "Because the water table in this entire region is well high, Laterite has been used in the underlying layers of Angkor Wat and other temples (especially the larger ones), because it can absorb water and help towards better stability of the Temple.File:Preah Ko 1.jpg|Preah Ko, completed in 879 CE, was a temple made mainly of brick.File:Ta Keo 01.jpg|Ta Keo, a temple built in the 10th century, was constructed more or less entirely from sandstone.File:Prasat Prang Ku Somboon-006.jpg|Prasat Prang Ku in Sisaket, Thailand, was built with laterite." ], [ "Structures", "===Central sanctuary===mount Meru.The central sanctuary of an Angkorian temple was home to the temple's primary deity, the one to whom the site was dedicated: typically Shiva or Vishnu in the case of a Hindu temple, Buddha or a bodhisattva in the case of a Buddhist temple.", "The deity was represented by a statue (or in the case of Shiva, most commonly by a linga).", "Since the temple was not considered a place of worship for use by the population at large, but rather a home for the deity, the sanctuary needed only to be large enough to hold the statue or linga; it was never more than a few metres across.", "Its importance was instead conveyed by the height of the tower (''prasat'') rising above it, by its location at the centre of the temple, and by the greater decoration on its walls.", "Symbolically, the sanctuary represented Mount Meru, the legendary home of the Hindu gods.===Prang===The prang is the tall finger-like spire, usually richly carved, common to much Khmer religious architecture.===Enclosure===Khmer temples were typically enclosed by a concentric series of walls, with the central sanctuary in the middle; this arrangement represented the mountain ranges surrounding Mount Meru, the mythical home of the gods.", "Enclosures are the spaces between these walls, and between the innermost wall and the temple itself.", "By modern convention, enclosures are numbered from the centre outwards.", "The walls defining the enclosures of Khmer temples are frequently lined by galleries, while passage through the walls is by way of gopuras located at the cardinal points.===Gallery===A cruciform gallery separates the courtyards at Angkor Wat.A gallery is a passageway running along the wall of an enclosure or along the axis of a temple, often open to one or both sides.", "Historically, the form of the gallery evolved during the 10th century from the increasingly long hallways which had earlier been used to surround the central sanctuary of a temple.", "During the period of Angkor Wat in the first half of the 12th century, additional half galleries on one side were introduced to buttress the structure of the temple.===Gopura===A gopura leads into the 12th-century temple compound at Ta Prohm.Many of the gopuras constructed under Jayavarman VII toward the end of the 12th century, such as this one at Angkor Thom, are adorned with gigantic stone faces of Avalokiteshvara.A gopura is an entrance building.", "At Angkor, passage through the enclosure walls surrounding a temple compound is frequently accomplished by means of an impressive gopura, rather than just an aperture in the wall or a doorway.", "Enclosures surrounding a temple are often constructed with a gopura at each of the four cardinal points.", "In plan, gopuras are usually cross-shaped and elongated along the axis of the enclosure wall.If the wall is constructed with an accompanying gallery, the gallery is sometimes connected to the arms of the gopura.", "Many Angkorian gopuras have a tower at the centre of the cross.", "The lintels and pediments are often decorated, and guardian figures (dvarapalas) are often placed or carved on either side of the doorways.===Hall of Dancers===A Hall of Dancers is the structure of a type found in certain late 12th-century temples constructed under King Jayavarman VII: Ta Prohm, Preah Khan, Banteay Kdei and Banteay Chhmar.", "It is a rectangular building elongated along the temple's east axis and divided into four courtyards by galleries.", "Formerly it had a roof made of perishable materials; now only the stone walls remain.", "The pillars of the galleries are decorated with carved designs of dancing apsaras; hence scholars have suggested that the hall itself may have been used for dancing.===House of Fire===House of Fire, or ''Dharmasala'', is the name given to a type of building found only in temples constructed during the reign of late 12th-century monarch Jayavarman VII: Preah Khan, Ta Prohm and Banteay Chhmar.", "A House of Fire has thick walls, a tower at the west end and south-facing windows.Scholars theorize that the House of Fire functioned as a \"rest house with fire\" for travellers.", "An inscription at Preah Khan tells of 121 such rest houses lining the highways into Angkor.", "The Chinese traveller Zhou Daguan expressed his admiration for these rest houses when he visited Angkor in 1296 CE.", "Another theory is that the House of Fire had a religious function as the repository the sacred flame used in sacred ceremonies.Unusually, the libraries at Angkor Wat open to both the East and the West.===Library===Structures conventionally known as \"libraries\" are a common feature of the Khmer temple architecture, but their true purpose remains unknown.", "Most likely they functioned broadly as religious shrines rather than strictly as repositories of manuscripts.", "Freestanding buildings, they were normally placed in pairs on either side of the entrance to an enclosure, opening to the west.===Srah and baray===Srahs and barays were reservoirs, generally created by excavation and embankment, respectively.", "It is not clear whether the significance of these reservoirs was religious, agricultural, or a combination of the two.The two largest reservoirs at Angkor were the West Baray and the East Baray located on either side of Angkor Thom.", "The East Baray is now dry.", "The West Mebon is an 11th-century temple standing at the center of the West Baray and the East Mebon is a 10th-century temple standing at the center of the East Baray.The baray associated with Preah Khan is the Jayataka, in the middle of which stands the 12th-century temple of Neak Pean.", "Scholars have speculated that the Jayataka represents the Himalayan lake of Anavatapta, known for its miraculous healing powers.===Temple mountain===The Bakong is the earliest surviving Temple Mountain at Angkor.The dominant scheme for the construction of state temples in the Angkorian period was that of the Temple Mountain, an architectural representation of Mount Meru, the home of the gods in Hinduism.", "Enclosures represented the mountain chains surrounding Mount Meru, while a moat represented the ocean.", "The temple itself took shape as a pyramid of several levels, and the home of the gods was represented by the elevated sanctuary at the center of the temple.The first great temple mountain was the Bakong, a five-level pyramid dedicated in 881 by King Indravarman I.", "The structure of Bakong took shape of stepped pyramid, popularly identified as temple mountain of early Khmer temple architecture.", "The striking similarity of the Bakong and Borobudur in Java, going into architectural details such as the gateways and stairs to the upper terraces, strongly suggests that Borobudur might have served as the prototype of Bakong.", "There must have been exchanges of travelers, if not mission, between Khmer kingdom and the Sailendras in Java.", "Transmitting to Cambodia not only ideas, but also technical and architectural details of Borobudur, including arched gateways in corbelling method.Other Khmer temple mountains include Baphuon, Pre Rup, Ta Keo, Koh Ker, the Phimeanakas, and most notably the Phnom Bakheng at Angkor.According to Charles Higham, \"A temple was built for the worship of the ruler, whose essence, if a Saivite, was embodied in a linga... housed in the central sanctuary which served as a temple-mausoleum for the ruler after his death...these central temples also contained shrines dedicated to the royal ancestors and thus became centres of ancestor worship\"." ], [ "Elements", "===Bas-relief===Bas-reliefs are individual figures, groups of figures, or entire scenes cut into stone walls, not as drawings but as sculpted images projecting from a background.", "Sculpture in bas-relief is distinguished from sculpture in haut-relief, in that the latter projects farther from the background, in some cases almost detaching itself from it.", "The Angkorian Khmer preferred to work in bas-relief, while their neighbors the Cham were partial to haut-relief.Narrative bas-reliefs are bas-reliefs depicting stories from mythology or history.", "Until about the 11th century, the Angkorian Khmer confined their narrative bas-reliefs to the space on the tympana above doorways.", "The most famous early narrative bas-reliefs are those on the tympana at the 10th-century temple of Banteay Srei, depicting scenes from Hindu mythology as well as scenes from the great works of Indian literature, the Ramayana and the Mahabharata.By the 12th century, however, the Angkorian artists were covering entire walls with narrative scenes in bas-relief.", "At Angkor Wat, the external gallery wall is covered with some 12,000 or 13,000 square meters of such scenes, some of them historical, some mythological.", "Similarly, the outer gallery at the Bayon contains extensive bas-reliefs documenting the everyday life of the medieval Khmer as well as historical events from the reign of King Jayavarman VII.tympanum at Banteay Srei shows Indra releasing the rains in an attempt to extinguish the fire created by Agni.The Battle of Kurukshetra is the subject of this bas-relief at Angkor Wat.This scene from the outer gallery at the Bayon shows Chinese expats negotiating with Khmer merchants at an Angkorean market.The following is a listing of the motifs illustrated in some of the more famous Angkorian narrative bas-reliefs:* bas-reliefs in the tympana at Banteay Srei (10th century)** the duel of the monkey princes Vali and Sugriva, and the intervention of the human hero Rama on behalf of the latter** the duel of Bhima and Duryodhana at the Battle of Kurukshetra** the Rakshasa king Ravana shaking Mount Kailasa, upon which sit Shiva and his shakti** Kama firing an arrow at Shiva as the latter sits on Mount Kailasa** the burning of Khandava Forest by Agni and Indra's attempt to extinguish the flames* bas-reliefs on the walls of the outer gallery at Angkor Wat (mid-12th century)** the Battle of Lanka between the Rakshasas and the vanaras or monkeys** the court and procession of King Suryavarman II, the builder of Angkor Wat** the Battle of Kurukshetra between Pandavas and Kauravas** the judgment of Yama and the tortures of Hell** the Churning of the Ocean of Milk** a battle between devas and asuras** a battle between Vishnu and a force of asuras** the conflict between Krishna and the asura Bana** the story of the monkey princes Vali and Sugriva* bas-reliefs on the walls of the outer and inner galleries at the Bayon (late 12th century)** battles on land and sea between Khmer and Cham troops** scenes from the everyday life of Angkor** civil strife among the Khmer** the legend of the Leper King** the worship of Shiva** groups of dancing apsarasThis blind door at Banteay Srei is flanked by colonettes.", "Above the door is a lintel, above which is a tympanum with a scene from the Mahabharata.===Blind door and window===Angkorean shrines frequently opened in only one direction, typically to the east.", "The other three sides featured fake or blind doors to maintain symmetry.", "Blind windows were often used along otherwise blank walls.===Colonnette===Colonnettes were narrow decorative columns that served as supports for the beams and lintels above doorways or windows.", "Depending on the period, they were round, rectangular, or octagonal in shape.", "Colonnettes were often circled with molded rings and decorated with carved leaves.===Corbelling===Angkorian engineers tended to use the corbel arch in order to construct rooms, passageways and openings in buildings.", "A corbel arch is constructed by adding layers of stones to the walls on either side of an opening, with each successive layer projecting further towards the centre than the one supporting it from below, until the two sides meet in the middle.", "The corbel arch is structurally weaker than the true arch.", "The use of corbelling prevented the Angkorian engineers from constructing large openings or spaces in buildings roofed with stone, and made such buildings particularly prone to collapse once they were no longer maintained.", "These difficulties did not, of course, exist for buildings constructed with stone walls surmounted by a light wooden roof.", "The problem of preventing the collapse of corbelled structures at Angkor remains a serious one for modern conservation.===Lintel, pediment, and tympanum===A lintel is a horizontal beam connecting two vertical columns between which runs a door or passageway.", "Because the Angkorean Khmer lacked the ability to construct a true arch, they constructed their passageways using lintels or corbelling.", "A pediment is a roughly triangular structure above a lintel.", "A tympanum is the decorated surface of a pediment.Lintel and pediment at Banteay Srei; the motif on the pediment is Shiva Nataraja.The styles employed by Angkorean artists in the decoration of lintels evolved over time, as a result, the study of lintels has proven a useful guide to the dating of temples.", "Some scholars have endeavored to develop a periodization of lintel styles.", "The most beautiful Angkorean lintels are thought to be those of the Preah Ko style from the late 9th century.Common motifs in the decoration of lintels include the kala, the nāga and the makara, as well as various forms of vegetation.", "Also frequently depicted are the Hindu gods associated with the four cardinal directions, with the identity of the god depicted on a given lintel or pediment depending on the direction faced by that element.", "Indra, the god of the sky, is associated with East; Yama, the god of judgment and Hell, with South; Varuna, the god of the ocean, with West; and Kubera, god of wealth, with North.====List of Khmer lintel styles====*Sambor Prei Kuk style: inward-facing makaras with tapering bodies.", "Four arches joined by three medallions, the central once carved with Indra.", "Small figure on each makara.", "A variation is with figures replacing the makaras and a scene with figures below the arch.", "*Prei Khmeng style: continuation of Sambor Prei Kuk but makaras disappear, being replaced by incurving ends and figures.", "Arches more rectilinear.", "Large figures sometimes at each end.", "A variation is a central scene below the arch, usually Vishnu Reclining.", "*Kompong Preah style: high quality carving.", "Arches replaced by a garland of vegetation (like a wreath) more or less segmented.", "Medallions disappear, central one sometimes replaced by a knot of leaves.", "Leafy pendants spray out above and below garland.", "*Kulen style: great diversity, with influences from Champa and Java, including the kala and outward-facing makaras.", "*Preah Ko style: some of the most beautiful of all Khmer lintels, rich, will-carved and imaginative.", "Kala in center, issuing garland on either side.", "Distinct loops of vegetation curl down from garland.", "Outward-facing makaras sometimes appear at the ends.", "Vishnu on Garuda common.Rich-carved decoration of Preah Ko lintel*Bakheng style: continuation of Preah Ko but less fanciful and tiny figures disappear.", "Loop of vegetation below the naga form tight circular coils.", "Garland begins to dip in the center.", "*Koh Ker style: center occupied by a prominent scene, taking up almost the entire height of the lintel.", "Usually no lower border.", "Dress of figures shows a curved line to the sampot tucked in below waist.", "*Pre Rup style: tendency to copy earlier style, especially Preah Ko and Bakheng.", "Central figures.", "Re-appearance of lower border.", "*Banteay Srei style: increase in complexity and detail.", "Garland sometimes makes pronounced loop on either side with kala at top of each loop.", "Central figure.", "*Khleang style: less ornate than those of Banteay Srei.", "Central kala with triangular tongue, its hands holding the garland which is bent at the center.", "Kala sometimes surmounted by a divinity.", "Loops of garland on either side divided by flora stalk and pendant.", "Vigorous treatment of vegetation.", "*Baphuon style: the central kala surmounted by divinity, usually riding a steed or a Vishnu scene, typically from the life of Krishna.", "Loops of garland no longer cut.", "Another type is a scene with many figures and little vegetation.", "*Angkor Wat style: centered, framed and linked by garlands.", "A second type is a narrative scene filled with figures.", "When nagas appear, they curls are tight and prominent.", "Dress mirrors that of devatas and apsaras in bas-reliefs.", "No empty spaces.", "*Bayon style: most figures disappear, usually only a kala at the bottom of the lintel surmounted by small figure.", "Mainly Buddhist motifs.", "In the middle of the period the garland is cut into four parts, while later a series of whorls of foliage replace the four divisions.===Stairs===The stairs leading to the inner enclosure at Ankor Wat are daunting.Angkorean stairs are notoriously steep.", "Frequently, the length of the riser exceeds that of the tread, producing an angle of ascent somewhere between 45 and 70 degrees.", "The reasons for this peculiarity appear to be both religious and monumental.", "From the religious perspective, a steep stairway can be interpreted as a \"stairway to heaven\", the realm of the gods.", "\"From the monumental point of view\", according to Angkor-scholar Maurice Glaize, \"the advantage is clear – the square of the base not having to spread in surface area, the entire building rises to its zenith with a particular thrust\"." ], [ "Motifs", "===Apsara and devata===Apsaras, divine nymphs or celestial dancing girls, are characters from Indian mythology.", "Their origin is explained in the story of the churning of the Ocean of Milk, or samudra manthan, found in the Vishnu Purana.", "Other stories in the Mahabharata detail the exploits of individual apsaras, who were often used by the gods as agents to persuade or seduce mythological demons, heroes and ascetics.", "The widespread use of apsaras as a motif for decorating the walls and pillars of temples and other religious buildings, however, was a Khmer innovation.", "In modern descriptions of Angkorian temples, the term \"apsara\" is sometimes used to refer not only to dancers but also to other minor female deities, though minor female deities who are depicted standing rather than dancing are more commonly called \"devatas\".Apsaras and devatas are ubiquitous at Angkor, but are most common in the foundations of the 12th century.", "Depictions of true (dancing) apsaras are found, for example, in the Hall of Dancers at Preah Khan, in the pillars that line the passageways through the outer gallery of the Bayon, and in the famous bas-relief of Angkor Wat depicting the churning of the Ocean of Milk.", "The largest population of devatas (around 2,000) is at Angkor Wat, where they appear individually and in groups.This '''dvarapala''' stands guard at Banteay Kdei.===Dvarapala===Dvarapalas are human or demonic temple guardians, generally armed with lances and clubs.", "They are presented either as a stone statues or as relief carvings in the walls of temples and other buildings, generally close to entrances or passageways.", "Their function is to protect the temples.", "Dvarapalas may be seen, for example, at Preah Ko, Lolei, Banteay Srei, Preah Khan and Banteay Kdei.===Gajasimha and Reachisey===The gajasimha is a mythical animal with the body of a lion and the head of an elephant.", "At Angkor, it is portrayed as a guardian of temples and as a mount for some warriors.", "The gajasimha may be found at Banteay Srei and at the temples belonging to the Roluos group.The reachisey is another mythical animal, similar to the gajasimha, with the head of a lion, a short elephantine trunk, and the scaly body of a dragon.", "It occurs at Angkor Wat in the epic bas reliefs of the outer gallery.===Garuda===In this 9th century lintel, now on display at the Musée Guimet, '''Garuda''' bears Vishnu on his shoulders.Garuda is a divine being that is part man and part bird.", "He is the lord of birds, the mythological enemy of nāgas, and the battle steed of Vishnu.", "Depictions of Garuda at Angkor number in the thousands, and though Indian in inspiration exhibit a style that is uniquely Khmer.", "They may be classified as follows:* As part of a narrative bas relief, Garuda is shown as the battle steed of Vishnu or Krishna, bearing the god on his shoulders, and simultaneously fighting against the god's enemies.", "Numerous such images of Garuda may be observed in the outer gallery of Angkor Wat.", "* Garuda serves as an atlas supporting a superstructure, as in the bas relief at Angkor Wat that depicts heaven and hell.", "Garudas and stylized mythological lions are the most common atlas figures at Angkor.", "* Garuda is depicted in the pose of a victor, often dominating a nāga, as in the gigantic relief sculptures on the outer wall of Preah Khan.", "In this context, Garuda symbolizes the military power of the Khmer kings and their victories over their enemies.", "Not coincidentally, the city of Preah Khan was built on the site of King Jayavarman VII's victory over invaders from Champa.", "* In free-standing nāga sculptures, such as in nāga bridges and balustrades, Garuda is often depicted in relief against the fan of nāga heads.", "The relationship between Garuda and the nāga heads is ambiguous in these sculptures: it may be one of cooperation, or it may again be one of domination of the nāga by Garuda.===Indra===In the ancient religion of the Vedas, Indra the sky-god reigned supreme.", "In the medieval Hinduism of Angkor, however, he had no religious status, and served only as a decorative motif in architecture.", "Indra is associated with the East; since Angkorian temples typically open to the East, his image is sometimes encountered on lintels and pediments facing that direction.", "Typically, he is mounted on the three-headed elephant Airavata and holds his trusty weapon, the thunderbolt or vajra.", "The numerous adventures of Indra documented in Hindu epic Mahabharata are not depicted at Angkor.===Kala===A '''kala''' serves as the base for a deity at the 10th-century Hindu temple Banteay Srei.The kala is a ferocious monster symbolic of time in its all-devouring aspect and associated with the destructive side of the god Siva.", "In Khmer temple architecture, the kala serves as a common decorative element on lintels, tympana and walls, where it is depicted as a monstrous head with a large upper jaw lined by large carnivorous teeth, but with no lower jaw.", "Some kalas are shown disgorging vine-like plants, and some serve as the base for other figures.Scholars have speculated that the origin of the kala as a decorative element in Khmer temple architecture may be found in an earlier period when the skulls of human victims were incorporated into buildings as a kind of protective magic or apotropaism.", "Such skulls tended to lose their lower jaws when the ligaments holding them together dried out.", "Thus, the kalas of Angkor may represent the Khmer civilization's adoption into its decorative iconography of elements derived from long forgotten primitive antecedents.===Krishna===Scenes from the life of Krishna, a hero and Avatar of the god Vishnu, are common in the relief carvings decorating Angkorian temples, and unknown in Angkorian sculpture in the round.", "The literary sources for these scenes are the Mahabharata, the Harivamsa, and the Bhagavata Purana.", "The following are some of the most important Angkorian depictions of the life of Krishna:* A series of bas reliefs at the 11th-century temple pyramid called Baphuon depicts scenes of the birth and childhood of Krishna.", "* Numerous bas reliefs in various temples show Krishna subduing the nāga Kaliya.", "In Angkorian depictions, Krishna is shown effortlessly stepping on and pushing down his opponent's multiple heads.", "* Also common is the depiction of Krishna as he lifts Mount Govardhana with one hand in order to provide the cowherds with shelter from the deluge caused by Indra.", "* Krishna is frequently depicted killing or subduing various demons, including his evil uncle Kamsa.", "An extensive bas relief in the outer gallery of Angkor Wat depicts Krishna's battle with the asura Bana.", "In battle, Krishna is shown riding on the shoulders of Garuda, the traditional mount of Vishnu.", "* In some scenes, Krishna is depicted in his role as charioteer, advisor and protector of Arjuna, the hero of the Mahabharata.", "A well-known bas relief from the 10th-century temple of Banteay Srei depicts the Krishna and Arjuna helping Agni to burn down Khandava forest.===Linga===This segmented '''linga''' from 10th century Angkor has a square base, an octagonal middle, and a round tip.The linga is a phallic post or cylinder symbolic of the god Shiva and of creative power.", "As a religious symbol, the function of the linga is primarily that of worship and ritual, and only secondarily that of decoration.", "In the Khmer empire, certain lingas were erected as symbols of the king himself, and were housed in royal temples in order to express the king's consubstantiality with Siva.", "The lingas that survive from the Angkorean period are generally made of polished stone.The lingas of the Angkorian period are of several different types.", "* Some lingas are implanted in a flat square base called a yoni, symbolic of the womb.", "* On the surface of some lingas is engraved the face of Siva.", "Such lingas are called mukhalingas.", "* Some lingas are segmented into three parts: a square base symbolic of Brahma, an octagonal middle section symbolic of Vishnu, and a round tip symbolic of Shiva.===Makara===The corner of a lintel on one of the brick towers at Bakong shows a man riding on the back of a '''makara''' that in turn disgorges another monster.A makara is a mythical sea monster with the body of a serpent, the trunk of an elephant, and a head that can have features reminiscent of a lion, a crocodile, or a dragon.", "In Khmer temple architecture, the motif of the makara is generally part of a decorative carving on a lintel, tympanum, or wall.", "Often the makara is depicted with some other creature, such as a lion or serpent, emerging from its gaping maw.", "The makara is a central motif in the design of the famously beautiful lintels of the Roluos group of temples: Preah Ko, Bakong, and Lolei.", "At Banteay Srei, carvings of makaras disgorging other monsters may be observed on many of the corners of the buildings.===Nāga===Mucalinda, the '''nāga''' king who shielded Buddha as he sat in meditation, was a favorite motif for Cambodian Buddhist sculptors from the 11th century.", "This statue is dated between 1150 and 1175 CE.Mythical serpents, or nāgas, represent an important motif in Khmer architecture as well as in free-standing sculpture.", "They are frequently depicted as having multiple heads, always uneven in number, arranged in a fan.", "Each head has a flared hood, in the manner of a cobra.This multi-headed '''nāga''' is part of a decorative lintel from the end of the 9th century.Nāgas are frequently depicted in Angkorian lintels.", "The composition of such lintels characteristically consists in a dominant image at the center of a rectangle, from which issue swirling elements that reach to the far ends of the rectangle.", "These swirling elements may take shape as either vinelike vegetation or as the bodies of nāgas.", "Some such nāgas are depicted wearing crowns, and others are depicted serving as mounts for human riders.To the Angkorian Khmer, nāgas were symbols of water and figured in the myths of origin for the Khmer people, who were said to be descended from the union of an Indian Brahman and a serpent princess from Cambodia.", "Nāgas were also characters in other well-known legends and stories depicted in Khmer art, such as the churning of the Ocean of Milk, the legend of the Leper King as depicted in the bas-reliefs of the Bayon, and the story of Mucalinda, the serpent king who protected the Buddha from the elements.===Nāga Bridge===Asuras hold the '''nāga''' Vasuki on a bridge leading into the 12th century city of Angkor Thom.Nāga bridges are causeways or true bridges lined by stone balustrades shaped as nāgas.In some Angkorian nāga-bridges, as for example those located at the entrances to 12th century city of Angkor Thom, the nāga-shaped balustrades are supported not by simple posts but by stone statues of gigantic warriors.", "These giants are the devas and asuras who used the nāga king Vasuki in order to the churn the Ocean of Milk in quest of the amrita or elixir of immortality.", "The story of the Churning of the Ocean of Milk or samudra manthan has its source in Indian mythology.===Quincunx===A '''linga''' in the form of a '''quincunx''', set inside a yoni, is carved into the riverbed at Kbal Spean.A quincunx is a spatial arrangement of five elements, with four elements placed as the corners of a square and the fifth placed in the center.", "The five peaks of Mount Meru were taken to exhibit this arrangement, and Khmer temples were arranged accordingly in order to convey a symbolic identification with the sacred mountain.", "The five brick towers of the 10th-century temple known as East Mebon, for example, are arranged in the shape of a quincunx.", "The quincunx also appears elsewhere in designs of the Angkorian period, as in the riverbed carvings of Kbal Spean.===Shiva===Most temples at Angkor are dedicated to Shiva.", "In general, the Angkorian Khmer represented and worshipped Shiva in the form of a lingam, though they also fashioned anthropomorphic statues of the god.", "Anthropomorphic representations are also found in Angkorian bas reliefs.", "A famous tympanum from Banteay Srei depicts Shiva sitting on Mount Kailasa with his consort, while the demon king Ravana shakes the mountain from below.", "At Angkor Wat and Bayon, Shiva is depicted as a bearded ascetic.", "His attributes include the mystical eye in the middle of his forehead, the trident, and the rosary.", "His vahana or mount is the bull Nandi.===Vishnu===Angkorian representations of Vishnu include anthropomorphic representations of the god himself, as well as representations of his incarnations or Avatars, especially Rama and Krishna.", "Depictions of Vishnu are prominent at Angkor Wat, the 12th-century temple that was originally dedicated to Vishnu.", "Bas reliefs depict Vishna battling with against asura opponents, or riding on the shoulders of his vahana or mount, the gigantic eagle-man Garuda.", "Vishnu's attributes include the discus, the conch shell, the baton, and the orb." ], [ "Wooden architecture", "===Palaces===During the Angkor era, the architectural landscape consisted predominantly of temples constructed from durable materials such as brick, sandstone, and laterite.", "In stark contrast, the royal residences of the Khmer courts were predominantly crafted from wood and other perishable materials, rendering them susceptible to the ravages of time and leaving no trace of their existence in the present day.", "The enduring remnants of this era are the brick or stone temples, such as those found in the Angkor complex, which stand as the sole vestiges of what was once expansive wooden settlements and palaces.However, a meticulous 13th-century account by a Chinese emissary to Angkor provides a detailed description of the palace, depicting it as an assemblage of imposing structures crowned with lead-tiled roofs.", "Intricately carved bas reliefs at Bayon and Banteay Chhmar portray various wooden buildings featuring triangular pediments and roofs, identified as representative of the royal halls within Angkorian palaces.", "As the Khmer people gradually embraced Buddhism, a discernible transition from stone temples to wooden architecture occurred.", "This shift marked the adoption of wooden structures as the new norm in Khmer architecture, supplanting the erstwhile prominence of stone temples in earlier periods.===Ordinary housing===The nuclear family, in rural Cambodia, typically lives in a rectangular house that may vary in size from four by six meters to six by ten meters.", "It is constructed of a wooden frame with gabled thatch roof and walls of woven bamboo.", "Khmer houses typically are raised on stilts as much as three meters for protection from annual floods.", "Two ladders or wooden staircases provide access to the house.", "The steep thatch roof overhanging the house walls protects the interior from rain.", "Typically a house contains three rooms separated by partitions of woven bamboo.The front room serves as a living room used to receive visitors, the next room is the parents' bedroom, and the third is for unmarried daughters.", "Sons sleep anywhere they can find space.", "Family members and neighbors work together to build the house, and a house-raising ceremony is held upon its completion.", "The houses of poorer persons may contain only a single large room.", "Food is prepared in a separate kitchen located near the house but usually behind it.", "Toilet facilities consist of simple pits in the ground, located away from the house, that are covered up when filled.", "Any livestock is kept below the house.Chinese and Vietnamese houses in Cambodian town and villages typically are built directly on the ground and have earthen, cement, or tile floors, depending upon the economic status of the owner.", "Urban housing and commercial buildings may be of brick, masonry, or wood." ], [ "See also", "*New Khmer Architecture*Rural Khmer house*Khmer sculpture'''Indian influence:'''*Influence of Indian Hindu temple architecture on Southeast Asia*History of Indian influence on Southeast Asia" ], [ "References" ], [ "Bibliography", "*Coedès, George.", "''Pour mieux comprendre Angkor''.", "Hanoi: Imprimerie d'Extrême-Orient, 1943.", "*Forbes, Andrew; Henley, David (2011).", "''Angkor, Eighth Wonder of the World''.", "Chiang Mai: Cognoscenti Books.", ".", "*Freeman, Michael and Jacques, Claude.", "''Ancient Angkor''.", "Bangkok: River Books, 1999..*Glaize, Maurice.", "''The Monuments of the Angkor Group''.", "1944.A translation from the original French into English is available online at theangkorguide.com.", "*Jessup, Helen Ibbitson.", "''Art & Architecture of Cambodia''.", "London: Thames & Hudson, 2004.", "*Ngô Vǎn Doanh, ''Champa:Ancient Towers''.", "Hanoi: The Gioi Publishers, 2006.", "*Roveda, Vittorio.", "''Images of the Gods: Khmer Mythology in Cambodia, Laos & Thailand''.", "Bangkok: River Books, 2005.*Sthapatyakam.", "''The Architecture of Cambodia''.", "Phnom Penh: Department of Media and Communication, Royal University of Phnom Penh, 2012.", "*Gabel, Joachim. ''", "Earliest Khmer Stone Architecture and its Origin: A Case Study of Megalithic Remains and Spirit Belief at the Site of Vat Phu..'' In: JoGA 2022: 2–137, Journal of Global Archaeology." ], [ "External links", "* ''Churning the Sea of Time'' (documentary film) on IMDb" ] ]

[ [ "Capricorn" ], [ "Introduction", "'''Capricorn''' (pl.", "''capricorni'' or ''capricorns'') may refer to:" ], [ "Places", "*Capricorn and Bunker Group, islands of the southern Great Barrier Reef, Australia*Capricorn District Municipality, Limpopo province, South Africa" ], [ "Animals", "*Capricorn, an animal from the ibex family, particularly the Alpine ibex*Capricornis, a genus of goat-like or antelope-like animals" ], [ "Astronomy and astrology", "* Capricornus, one of the constellations of the zodiac** Capricorn (astrology)" ], [ "Arts, entertainment, and media", "===Fictional characters===*Capricorn (comics), several Marvel Comics characters*Capricorn (''Inkworld''), ''Inkheart'' character===Music=======Groups and labels====* Capricorn Records, an American record label active 1969–1979* Capricorn (ensemble), a British chamber ensemble active 1973–2000====Albums====*''Capricorn'' (Jay Chou album), 2008*''Capricorn'' (Trevor Powers album), 2020*''Capricorn'' (Mike Tramp album), 1997*\"Capricorn (A Brand New Name)\", a 2002 single by 30 Seconds to Mars from their self-titled album====Songs====*\"Capricorn\", a song by IQ from their 1997 concept album ''Subterranea''*\"Capricorn\", a song by Barclay James Harvest from the album ''Eyes of the Universe''*\"Capricorn\", a song by Motörhead from the album ''Overkill''*\"Capricorn\", a song by Vampire Weekend on the album \"Only God Was Above Us\"=== Other uses in arts, entertainment, and media ===* ''Capricorn'', a 1988 manga series created by Johji Manabe* ''Capricorn One'', a 1977 thriller" ], [ "Brands and enterprises", "*Capricorn (microprocessor), a family of microprocessors used in the HP series 80 scientific microcomputers*Capricorn, one of the names for the Virgin Atlantic GlobalFlyer*Capricorn Investment Holdings, an umbrella for the Capricorn group of companies" ], [ "Other uses", "*''Capricorn'', a ship that on January 28, 1980 collided with and sank the USCGC ''Blackthorn'' (WLB-391)*Capricorn Africa Society, a pressure group in British African colonies" ], [ "See also", "*Capricornia (disambiguation)*Tropic of Capricorn (disambiguation)" ] ]

[ [ "Capricornus" ], [ "Introduction", "'''Capricornus''' is one of the constellations of the zodiac.", "Its name is Latin for \"horned goat\" or \"goat horn\" or \"having horns like a goat's\", and it is commonly represented in the form of a sea goat: a mythical creature that is half goat, half fish.", "Capricornus is one of the 88 modern constellations, and was also one of the 48 constellations listed by the 2nd century astronomer Claudius Ptolemy.", "Its old astronomical symbol is 20px (♑︎).", "Under its modern boundaries it is bordered by Aquila, Sagittarius, Microscopium, Piscis Austrinus, and Aquarius.", "The constellation is located in an area of sky called the Sea or the Water, consisting of many water-related constellations such as Aquarius, Pisces and Eridanus.", "It is the smallest constellation in the zodiac." ], [ "Notable features", "The constellation Capricornus as it can be seen with the naked eye===Stars===Capricornus is a faint constellation, with only one star above magnitude 3; its alpha star has a magnitude of only 3.6.The brightest star in Capricornus is δ Capricorni, also called Deneb Algedi, with a magnitude of 2.9, located 39 light-years from Earth.", "Like several other stars such as Denebola and Deneb, it is named for the Arabic word for \"tail\" (''deneb''); its traditional name means \"the tail of the goat\".", "Deneb Algedi is a Beta Lyrae variable star (a type of eclipsing binary).", "It ranges by about 0.2 magnitudes with a period of 24.5 hours.The other bright stars in Capricornus range in magnitude from 3.1 to 5.1.α Capricorni is a multiple star.", "The primary (α2 Cap), 109 light-years from Earth, is a yellow-hued giant star of magnitude 3.6; the secondary (α1 Cap), 690 light-years from Earth, is a yellow-hued supergiant star of magnitude 4.3.The two stars are distinguishable by the naked eye, and both are themselves multiple stars.", "α1 Capricorni is accompanied by a star of magnitude 9.2; α2 Capricornus is accompanied by a star of magnitude 11.0; this faint star is itself a binary star with two components of magnitude 11.Also called Algedi or Giedi, the traditional names of α Capricorni come from the Arabic word for \"the kid\", which references the constellation's mythology.β Capricorni is a double star also known as Dabih.", "It is a yellow-hued giant star of magnitude 3.1, 340 light-years from Earth.", "The secondary is a blue-white hued star of magnitude 6.1.The two stars are distinguishable in binoculars.", "β Capricorni's traditional name comes from the Arabic phrase for \"the lucky stars of the slaughterer,\" a reference to ritual sacrifices performed by ancient Arabs at the heliacal rising of Capricornus.", "Another star visible to the naked eye is γ Capricorni, sometimes called Nashira (\"bringing good tidings\"); it is a white-hued giant star of magnitude 3.7, 139 light-years from Earth.", "π Capricorni is a double star with a blue-white hued primary of magnitude 5.1 and a white-hued secondary of magnitude 8.3.It is 670 light-years from Earth and the components are distinguishable in a small telescope.===Deep-sky objects===The globular cluster Messier 30 imaged by the Hubble Space TelescopeSeveral galaxies and star clusters are contained within Capricornus.", "Messier 30 is a globular cluster located 1 degree south of the galaxy group that contains NGC 7103.The constellation also harbors the wide spiral galaxy NGC 6907.Messier 30 (NGC 7099) is a centrally-condensed globular cluster of magnitude 7.5 .", "At a distance of 30,000 light-years, it has chains of stars extending to the north that are resolvable in small amateur telescopes.One galaxy group located in Capricornus is HCG 87, a group of at least three galaxies located 400 million light-years from Earth (redshift 0.0296).", "It contains a large elliptical galaxy, a face-on spiral galaxy, and an edge-on spiral galaxy.", "The face-on spiral galaxy is experiencing abnormally high rates of star formation, indicating that it is interacting with one or both members of the group.", "Furthermore, the large elliptical galaxy and the edge-on spiral galaxy, both of which have active nuclei, are connected by a stream of stars and dust, indicating that they too are interacting.", "Astronomers predict that the three galaxies may merge millions of years in the future to form a giant elliptical galaxy." ], [ "History", "The constellation was first attested in depictions on a cylinder-seal from around the 21st century BCE, it was explicitly recorded in the Babylonian star catalogues before 1000 BCE.", "In the Early Bronze Age the winter solstice occurred in the constellation, but due to the precession of the equinoxes, the December solstice now takes place in the constellation Sagittarius.", "The Sun is now in the constellation Capricorn (as distinct from the astrological sign) from late January through mid-February.Although the solstice during the northern hemisphere's winter no longer takes place while the sun is in the ''constellation'' Capricornus, as it did until 130 BCE, the ''astrological sign'' called Capricorn is still used to denote the position of the solstice, and the latitude of the sun's most southerly position continues to be called the ''Tropic of Capricorn'', a term which also applies to the line on the Earth at which the sun is directly overhead at local noon on the day of the December solstice.The planet Neptune was discovered by German astronomer Johann Galle, near Deneb Algedi (δ Capricorni) on 23 September 1846, as Capricornus can be seen best from Europe at 4:00 in September (although, by modern constellation boundaries established in the early 20th century CE, Neptune lay within the confines of Aquarius at the time of its discovery)." ], [ "Mythology", "Despite its faintness, the constellation Capricornus has one of the oldest mythological associations, having been consistently represented as a hybrid of a goat and a fish since the Middle Bronze Age, when the Babylonians used \"The Goat-Fish\" as a symbol of their god Ea.In Greek mythology, the constellation is sometimes identified as Amalthea, the goat that suckled the infant Zeus after his mother, Rhea, saved him from being devoured by his father, Cronos.", "Amalthea's broken horn was transformed into the cornucopia or \"horn of plenty\".Capricornus is also sometimes identified as Pan, the god with a goat's horns and legs, who saved himself from the monster Typhon by giving himself a fish's tail and diving into a river." ], [ "Visualizations", "Capricornus as a sea-goat from ''Urania's Mirror'' (1825)Capricornus's brighter stars are found on a triangle whose vertices are α2 Capricorni (Giedi), δ Capricorni (Deneb Algiedi), and ω Capricorni.", "Ptolemy's method of connecting the stars of Capricornus has been influential.", "Capricornus is usually drawn as a goat with the tail of a fish.Diagram of H.A.", "Rey's alternative way to connect the stars of the Capricornus constellationH.", "A. Rey has suggested an alternative visualization, which graphically shows a goat.", "The goat's head is formed by the triangle of stars ι Cap, θ Cap, and ζ Cap.", "The goat's horn sticks out with stars γ Cap and δ Cap.", "Star δ Cap, at the tip of the horn, is of the third magnitude.", "The goat's tail consists of stars β Cap and α2 Cap: star β Cap being of the third magnitude.", "The goat's hind foot consists of stars ψ Cap and ω Cap.", "Both of these stars are of the fourth magnitude." ], [ "Equivalents", "In Chinese astronomy, constellation Capricornus lies in ''The Black Tortoise of the North'' ().The Nakh peoples called this constellation Roofing Towers ().In the Society Islands, the figure of Capricornus was called ''Rua-o-Mere'', \"Cavern of parental yearnings\".In Indian astronomy and Indian astrology, it is called Makara, the crocodile." ], [ "See also", "*Capricornus in Chinese astronomy*Hippocampus (mythology), the mythological sea horse*IC 1337, galaxy" ], [ "Citations", ";Citations;References* * * * *" ], [ "External links", "* The Deep Photographic Guide to the Constellations: Capricornus* Ian Ridpath's Star Tales – Capricornus* Warburg Institute Iconographic Database (medieval and early modern images of Capricornus)" ] ]

[ [ "Cameroon" ], [ "Introduction", "'''Cameroon''' ( ; ), officially the '''Republic of Cameroon''' (), is a country in Central Africa.", "It shares boundaries with Nigeria to the west and north, Chad to the northeast, the Central African Republic to the east, and Equatorial Guinea, Gabon and the Republic of the Congo to the south.", "Its coastline lies on the Bight of Biafra, part of the Gulf of Guinea and the Atlantic Ocean.", "Due to its strategic position at the crossroads between West Africa and Central Africa, it has been categorized as being in both camps.", "Its nearly 27 million people speak 250 native languages, in addition to the national tongues of English and French, or both.Early inhabitants of the territory included the Sao civilisation around Lake Chad, and the Baka hunter-gatherers in the southeastern rainforest.", "Portuguese explorers reached the coast in the 15th century and named the area ''Rio dos Camarões'' (''Shrimp River''), which became ''Cameroon'' in English.", "Fulani soldiers founded the Adamawa Emirate in the north in the 19th century, and various ethnic groups of the west and northwest established powerful chiefdoms and fondoms.Cameroon became a German colony in 1884 known as Kamerun.", "After World War I, it was divided between France and the United Kingdom as League of Nations mandates.", "The Union des Populations du Cameroun (UPC) political party advocated independence, but was outlawed by France in the 1950s, leading to the national liberation insurgency fought between French and UPC militant forces until early 1971.In 1960, the French-administered part of Cameroon became independent, as the Republic of Cameroun, under President Ahmadou Ahidjo.", "The southern part of British Cameroons federated with it in 1961 to form the Federal Republic of Cameroon.", "The federation was abandoned in 1972.The country was renamed the United Republic of Cameroon in 1972 and back to the Republic of Cameroon in 1984 by a presidential decree by president Paul Biya.", "Biya, the incumbent president, has led the country since 1982 following Ahidjo's resignation; he previously held office as prime minister from 1975 onward.", "Cameroon is governed as a Unitary Presidential Republic.The official languages of Cameroon are French and English, the official languages of former French Cameroons and British Cameroons.", "Christianity is the majority religion in Cameroon, with significant minorities practising Islam and traditional faiths.", "It has experienced tensions from the English-speaking territories, where politicians have advocated for greater decentralisation and even complete separation or independence (as in the Southern Cameroons National Council).", "In 2017, tensions over the creation of an Ambazonian state in the English-speaking territories escalated into open warfare.Large numbers of Cameroonians live as subsistence farmers.", "The country is often referred to as \"Africa in miniature\" for its geological, linguistic and cultural diversity.", "Its natural features include beaches, deserts, mountains, rainforests, and savannas.", "Its highest point, at almost , is Mount Cameroon in the Southwest Region.", "Its most populous cities are Douala on the Wouri River, its economic capital and main seaport; Yaoundé, its political capital; and Garoua.", "Limbé in the southwest has a natural seaport.", "Cameroon is well known for its native music styles, particularly Makossa, Njang and Bikutsi, and for its successful national football team.", "It is a member state of the African Union, the United Nations, the (OIF), the Commonwealth of Nations, Non-Aligned Movement and the Organisation of Islamic Cooperation." ], [ "Etymology", "Originally, Cameroon was the exonym given by the Portuguese to the Wouri River, which they called ''Rio dos Camarões'' meaning \"river of shrimps\" or \"shrimp river\", referring to the then abundant Cameroon ghost shrimp.", "Today the country's name in Portuguese remains ''Camarões''." ], [ "History", "===Early history===Bamum script is a writing system developed by King Njoya in the late 19th century.Present-day Cameroon was first settled in the Neolithic Era.", "The longest continuous inhabitants are groups such as the Baka (Pygmies).", "From there, Bantu migrations into eastern, southern and central Africa are believed to have occurred about 2,000 years ago.", "The Sao culture arose around Lake Chad, , and gave way to the Kanem and its successor state, the Bornu Empire.", "Kingdoms, fondoms, and chiefdoms arose in the west.Portuguese sailors reached the coast in 1472.They noted an abundance of the ghost shrimp ''Lepidophthalmus turneranus'' in the Wouri River and named it (''Shrimp River''), which became ''Cameroon'' in English.", "Over the following few centuries, European interests regularised trade with the coastal peoples, and Christian missionaries pushed inland.In 1896, Sultan Ibrahim Njoya created the Bamum script, or Shu Mom, for the Bamum language.", "It is taught in Cameroon today by the Bamum Scripts and Archives Project.===German rule===Germany began to establish roots in Cameroon in 1868 when the Woermann Company of Hamburg built a warehouse.", "It was built on the estuary of the Wouri River.", "Later, Gustav Nachtigal made a treaty with one of the local kings to annex the region for the German emperor.", "The German Empire claimed the territory as the colony of Kamerun in 1884 and began a steady push inland; the natives resisted.", "Under the aegis of Germany, commercial companies were local administrations.", "These concessions used forced labour to run profitable banana, rubber, palm oil, and cocoa plantations.", "Even infrastructure projects relied on a regimen of forced labour.", "This economic policy was much criticised by the other colonial powers.===French and British rule===UPCWith the defeat of Germany in World War I, Kamerun became a League of Nations mandate territory and was split into French Cameroon () and British Cameroon in 1919.France integrated the economy of Cameroon with that of France and improved the infrastructure with capital investments and skilled workers, modifying the colonial system of forced labour.The British administered their territory from neighbouring Nigeria.", "Natives complained that this made them a neglected \"colony of a colony\".", "Nigerian migrant workers flocked to Southern Cameroons, ending forced labour altogether but angering the local natives, who felt swamped.", "The League of Nations mandates were converted into United Nations Trusteeships in 1946, and the question of independence became a pressing issue in French Cameroon.France outlawed the pro-independence political party, the Union of the Peoples of Cameroon (''Union des Populations du Cameroun''; UPC), on 13 July 1955.This prompted a long guerrilla war waged by the UPC and the assassination of several of the party's leaders, including Ruben Um Nyobè, Félix-Roland Moumié and Ernest Ouandie.", "In the British Cameroons, the question was whether to reunify with French Cameroon or join Nigeria; the British ruled out the option of independence.===Independence===Former president Ahmadou Ahidjo ruled from 1960 until 1982.On 1 January 1960, French Cameroun gained independence from France under President Ahmadou Ahidjo.", "On 1 October 1961, the formerly British Southern Cameroons gained independence from the United Kingdom by vote of the UN General Assembly and joined with French Cameroun to form the Federal Republic of Cameroon, a date which is now observed as Unification Day, a public holiday.", "Ahidjo used the ongoing war with the UPC to concentrate power in the presidency, continuing with this even after the suppression of the UPC in 1971.His political party, the Cameroon National Union (CNU), became the sole legal political party on 1 September 1966 and on 20 May 1972, a referendum was passed to abolish the federal system of government in favour of a United Republic of Cameroon, headed from Yaoundé.", "This day is now the country's National Day, a public holiday.", "Ahidjo pursued an economic policy of planned liberalism, prioritising cash crops and petroleum development.", "The government used oil money to create a national cash reserve, pay farmers, and finance major development projects; however, many initiatives failed when Ahidjo appointed unqualified allies to direct them.The national flag was changed on 20 May 1975.Two stars were removed, replaced with a large central star as a symbol of national unity.Ahidjo stepped down on 4 November 1982 and left power to his constitutional successor, Paul Biya.", "However, Ahidjo remained in control of the CNU and tried to run the country from behind the scenes until Biya and his allies pressured him into resigning.", "Biya began his administration by moving toward a more democratic government, but a failed coup d'état nudged him toward the leadership style of his predecessor.An economic crisis took effect in the mid-1980s to late 1990s as a result of international economic conditions, drought, falling petroleum prices, and years of corruption, mismanagement, and cronyism.", "Cameroon turned to foreign aid, cut government spending, and privatised industries.", "With the reintroduction of multi-party politics in December 1990, the former British Southern Cameroons pressure groups called for greater autonomy, and the Southern Cameroons National Council advocated complete secession as the Republic of Ambazonia.", "The 1992 Labour Code of Cameroon gives workers the freedom to belong to a trade union or not to belong to any trade union at all.", "It is the choice of a worker to join any trade union in their occupation, since there is more than one trade union in each occupation.Paul Biya has ruled the country since 1982.In June 2006, talks concerning a territorial dispute over the Bakassi peninsula were resolved.", "The talks involved President Paul Biya of Cameroon, then President Olusegun Obasanjo of Nigeria and then UN Secretary General Kofi Annan, and resulted in Cameroonian control of the oil-rich peninsula.", "The northern portion of the territory was formally handed over to the Cameroonian government in August 2006, and the remainder of the peninsula was left to Cameroon two years later, in 2008.The boundary change triggered a local separatist insurgency, as many Bakassians refused to accept Cameroonian rule.", "While most militants laid down their arms in November 2009, some carried on fighting for years.In February 2008, Cameroon experienced its worst violence in 15 years when a transport union strike in Douala escalated into violent protests in 31 municipal areas.In May 2014, in the wake of the Chibok schoolgirls kidnapping, presidents Paul Biya of Cameroon and Idriss Déby of Chad announced they were waging war on Boko Haram, and deployed troops to the Nigerian border.", "Boko Haram launched several attacks into Cameroon, killing 84 civilians in a December 2014 raid, but suffering a heavy defeat in a raid in January 2015.Cameroon declared victory over Boko Haram on Cameroonian territory in September 2018.Since November 2016, protesters from the predominantly English-speaking Northwest and Southwest regions of the country have been campaigning for continued use of the English language in schools and courts.", "People were killed and hundreds jailed as a result of these protests.", "In 2017, Biya's government blocked the regions' access to the Internet for three months.", "In September, separatists started a guerilla war for the independence of the Anglophone region as the Federal Republic of Ambazonia.", "The government responded with a military offensive, and the insurgency spread across the Northwest and Southwest regions.", ", fighting between separatist guerillas and government forces continues.", "During 2020, numerous terrorist attacks—many of them carried out without claims of credit—and government reprisals have led to bloodshed throughout the country.", "Since 2016, more than 450,000 people have fled their homes.", "The conflict indirectly led to an upsurge in Boko Haram attacks, as the Cameroonian military largely withdrew from the north to focus on fighting the Ambazonian separatists.More than 30,000 people in northern Cameroon fled to Chad after ethnic clashes over access to water between Musgum fishermen and ethnic Arab Choa herders in December 2021." ], [ "Politics and government", "Unity Palace – Cameroon PresidencyThe President of Cameroon is elected and creates policy, administers government agencies, commands the armed forces, negotiates and ratifies treaties, and declares a state of emergency.", "The president appoints government officials at all levels, from the prime minister (considered the official head of government), to the provincial governors and divisional officers.", "The president is selected by popular vote every seven years.", "There have been 2 presidents since the independence of Cameroon.The National Assembly makes legislation.", "The body consists of 180 members who are elected for five-year terms and meet three times per year.", "Laws are passed on a majority vote.", "The 1996 constitution establishes a second house of parliament, the 100-seat Senate.", "The government recognises the authority of traditional chiefs, fons, and lamibe to govern at the local level and to resolve disputes as long as such rulings do not conflict with national law.Cameroon's legal system is a mixture of civil law, common law, and customary law.", "Although nominally independent, the judiciary falls under the authority of the executive's Ministry of Justice.", "The president appoints judges at all levels.", "The judiciary is officially divided into tribunals, the court of appeal, and the supreme court.", "The National Assembly elects the members of a nine-member High Court of Justice that judges high-ranking members of government in the event they are charged with high treason or harming national security.===Political culture===Bana, West RegionCameroon is viewed as rife with corruption at all levels of government.", "In 1997, Cameroon established anti-corruption bureaus in 29 ministries, but only 25% became operational, and in 2012, Transparency International placed Cameroon at number 144 on a list of 176 countries ranked from least to most corrupt.", "On 18 January 2006, Biya initiated an anti-corruption drive under the direction of the National Anti-Corruption Observatory.", "There are several high corruption risk areas in Cameroon, for instance, customs, public health sector and public procurement.", "However, the corruption has gotten worse, regardless of the existing anti-corruption bureaus, as Transparency International ranked Cameroon 152 on a list of 180 countries in 2018.President Biya's Cameroon People's Democratic Movement (CPDM) was the only legal political party until December 1990.Numerous regional political groups have since formed.", "The primary opposition is the Social Democratic Front (SDF), based largely in the Anglophone region of the country and headed by John Fru Ndi.Biya and his party have maintained control of the presidency and the National Assembly in national elections, which rivals contend were unfair.", "Human rights organisations allege that the government suppresses the freedoms of opposition groups by preventing demonstrations, disrupting meetings, and arresting opposition leaders and journalists.", "In particular, English-speaking people are discriminated against; protests often escalate into violent clashes and killings.", "In 2017, President Biya shut down the Internet in the English-speaking region for 94 days, at the cost of hampering five million people, including Silicon Mountain startups.Freedom House ranks Cameroon as \"not free\" in terms of political rights and civil liberties.", "The last parliamentary elections were held on 9 February 2020.===Foreign relations===President Paul Biya with U.S. President Barack Obama in 2014Cameroon is a member of both the Commonwealth of Nations and La Francophonie.Its foreign policy closely follows that of its main ally, France (one of its former colonial rulers).", "Cameroon relies heavily on France for its defence, although military spending is high in comparison to other sectors of government.President Biya has engaged in a decades-long clash with the government of Nigeria over possession of the oil-rich Bakassi peninsula.", "Cameroon and Nigeria share a 1,000-mile (1,600 km) border and have disputed the sovereignty of the Bakassi peninsula.", "In 1994 Cameroon petitioned the International Court of Justice to resolve the dispute.", "The two countries attempted to establish a cease-fire in 1996; however, fighting continued for years.", "In 2002, the ICJ ruled that the Anglo-German Agreement of 1913 gave sovereignty to Cameroon.", "The ruling called for a withdrawal by both countries and denied the request by Cameroon for compensation due to Nigeria's long-term occupation.", "By 2004, Nigeria had failed to meet the deadline to hand over the peninsula.", "A UN-mediated summit in June 2006 facilitated an agreement for Nigeria to withdraw from the region and both leaders signed the Greentree Agreement.", "The withdrawal and handover of control was completed by August 2006.In July 2019, UN ambassadors of 37 countries, including Cameroon, signed a joint letter to the UNHRC defending China's treatment of Uyghurs in the Xinjiang region.=== Military ===Military vehicles during a parade The Cameroon Armed Forces (French: ''Forces armées camerounaises'', FAC) consists of the country's army (''Armée de Terre''), the country's navy (''Marine Nationale de la République'' (MNR), includes naval infantry), the Cameroonian Air Force (''Armée de l'Air du Cameroun'', AAC), and the Gendarmerie.", "Males and females that are 18 years of age up to 23 years of age and have graduated high school are eligible for military service.", "Those who join are obliged to complete four years of service.", "There is no conscription in Cameroon, but the government makes periodic calls for volunteers.===Human rights===Human rights organisations accuse police and military forces of mistreating and even torturing criminal suspects, ethnic minorities, homosexuals, and political activists.", "United Nations figures indicate that more than 21,000 people have fled to neighbouring countries, while 160,000 have been internally displaced by the violence, many reportedly hiding in forests.", "Prisons are overcrowded with little access to adequate food and medical facilities, and prisons run by traditional rulers in the north are charged with holding political opponents at the behest of the government.", "However, since the first decade of the 21st century, an increasing number of police and gendarmes have been prosecuted for improper conduct.", "On 25 July 2018, UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein expressed deep concern about reports of violations and abuses in the English-speaking Northwest and Southwest regions of Cameroon.According to OCHA, more than 1.7 million people are in need of humanitarian assistance in the north-west and south-west regions.", "OCHA also estimates that at least 628,000 people have been internally displaced by violence in the two regions, while more than 87,000 have fled to Nigeria.Same-sex sexual acts are banned by section 347-1 of the penal code with a penalty of from 6 months up to 5 years' imprisonment.Since December 2020, Human Rights Watch claimed that Islamist armed group Boko Haram has stepped up attacks and killed at least 80 civilians in towns and villages in the Far North region of Cameroon.===Administrative divisions===Cameroon is divided into 10 regions.The constitution divides Cameroon into 10 semi-autonomous regions, each under the administration of an elected Regional Council.", "Each region is headed by a presidentially appointed governor.These leaders are charged with implementing the will of the president, reporting on the general mood and conditions of the regions, administering the civil service, keeping the peace, and overseeing the heads of the smaller administrative units.", "Governors have broad powers: they may order propaganda in their area and call in the army, gendarmes, and police.", "All local government officials are employees of the central government's Ministry of Territorial Administration, from which local governments also get most of their budgets.The regions are subdivided into 58 divisions (French ).", "These are headed by presidentially appointed divisional officers ().", "The divisions are further split into sub-divisions (), headed by assistant divisional officers ().", "The districts, administered by district heads (), are the smallest administrative units.The three northernmost regions are the Far North (), North (), and Adamawa ().", "Directly south of them are the Centre () and East ().", "The South Province () lies on the Gulf of Guinea and the southern border.", "Cameroon's western region is split into four smaller regions: the Littoral () and South-West () regions are on the coast, and the North-West () and West () regions are in the western grassfields." ], [ "Geography", "Volcanic plugs dot the landscape near Rhumsiki, Far North Region.At , Cameroon is the world's 53rd-largest country.", "The country is located in Central Africa, on the Bight of Bonny, part of the Gulf of Guinea and the Atlantic Ocean.", "Cameroon lies between latitudes 1° and 13°N, and longitudes 8° and 17°E.", "Cameroon controls 12 nautical miles of the Atlantic Ocean.Tourist literature describes Cameroon as \"Africa in miniature\" because it exhibits all major climates and vegetation of the continent: coast, desert, mountains, rainforest, and savanna.", "The country's neighbours are Nigeria and the Atlantic Ocean to the west; Chad to the northeast; the Central African Republic to the east; and Equatorial Guinea, Gabon and the Republic of the Congo to the south.Cameroon is divided into five major geographic zones distinguished by dominant physical, climatic, and vegetative features.", "The coastal plain extends inland from the Gulf of Guinea and has an average elevation of .", "Exceedingly hot and humid with a short dry season, this belt is densely forested and includes some of the wettest places on earth, part of the Cross-Sanaga-Bioko coastal forests.The South Cameroon Plateau rises from the coastal plain to an average elevation of .", "Equatorial rainforest dominates this region, although its alternation between wet and dry seasons makes it less humid than the coast.", "This area is part of the Atlantic Equatorial coastal forests ecoregion.Elephants in Waza National ParkAn irregular chain of mountains, hills, and plateaus known as the Cameroon range extends from Mount Cameroon on the coast—Cameroon's highest point at —almost to Lake Chad at Cameroon's northern border at 13°05'N.", "This region has a mild climate, particularly on the Western High Plateau, although rainfall is high.", "Its soils are among Cameroon's most fertile, especially around volcanic Mount Cameroon.", "Volcanism here has created crater lakes.", "On 21 August 1986, one of these, Lake Nyos, belched carbon dioxide and killed between 1,700 and 2,000 people.", "This area has been delineated by the World Wildlife Fund as the Cameroonian Highlands forests ecoregion.The southern plateau rises northward to the grassy, rugged Adamawa Plateau.", "This feature stretches from the western mountain area and forms a barrier between the country's north and south.", "Its average elevation is , and its average temperature ranges from to with high rainfall between April and October peaking in July and August.", "The northern lowland region extends from the edge of the Adamawa to Lake Chad with an average elevation of .", "Its characteristic vegetation is savanna scrub and grass.", "This is an arid region with sparse rainfall and high median temperatures.Cameroon has four patterns of drainage.", "In the south, the principal rivers are the Ntem, Nyong, Sanaga, and Wouri.", "These flow southwestward or westward directly into the Gulf of Guinea.", "The Dja and Kadéï drain southeastward into the Congo River.", "In northern Cameroon, the Bénoué River runs north and west and empties into the Niger.", "The Logone flows northward into Lake Chad, which Cameroon shares with three neighbouring countries.===Wildlife===" ], [ "Economy and infrastructure", "Cameroon's per capita GDP (Purchasing power parity) was estimated as US$3,700 in 2017.Major export markets include the Netherlands, France, China, Belgium, Italy, Algeria, and Malaysia.Cameroon has had a decade of strong economic performance, with GDP growing at an average of 4% per year.", "During the 2004–2008 period, public debt was reduced from over 60% of GDP to 10% and official reserves quadrupled to over US$3 billion.", "Cameroon is part of the Bank of Central African States (of which it is the dominant economy), the Customs and Economic Union of Central Africa (UDEAC) and the Organization for the Harmonization of Business Law in Africa (OHADA).", "Its currency is the CFA franc.Unemployment was estimated at 3.38% in 2019, and 23.8% of the population was living below the international poverty threshold of US$1.90 a day in 2014.Since the late 1980s, Cameroon has been following programmes advocated by the World Bank and International Monetary Fund (IMF) to reduce poverty, privatise industries, and increase economic growth.", "The government has taken measures to encourage tourism in the country.An estimated 70% of the population farms, and agriculture comprised an estimated 16.7% of GDP in 2017.Most agriculture is done at the subsistence scale by local farmers using simple tools.", "They sell their surplus produce, and some maintain separate fields for commercial use.", "Urban centres are particularly reliant on peasant agriculture for their foodstuffs.", "Soils and climate on the coast encourage extensive commercial cultivation of bananas, cocoa, oil palms, rubber, and tea.", "Inland on the South Cameroon Plateau, cash crops include coffee, sugar, and tobacco.", "Coffee is a major cash crop in the western highlands, and in the north, natural conditions favour crops such as cotton, groundnuts, and rice.", "Production of Fairtrade cotton was initiated in Cameroon in 2004.Dutch bulls and cows at Wallya community during the rainy season in CameroonLivestock are raised throughout the country.", "Fishing employs 5,000 people and provides over 100,000 tons of seafood each year.", "Bushmeat, long a staple food for rural Cameroonians, is today a delicacy in the country's urban centres.", "The commercial bushmeat trade has now surpassed deforestation as the main threat to wildlife in Cameroon.The southern rainforest has vast timber reserves, estimated to cover 37% of Cameroon's total land area.", "However, large areas of the forest are difficult to reach.", "Logging, largely handled by foreign-owned firms, provides the government US$60 million a year in taxes (), and laws mandate the safe and sustainable exploitation of timber.", "Nevertheless, in practice, the industry is one of the least regulated in Cameroon.Factory-based industry accounted for an estimated 26.5% of GDP in 2017.More than 75% of Cameroon's industrial strength is located in Douala and Bonabéri.", "Cameroon possesses substantial mineral resources, but these are not extensively mined (see ''Mining in Cameroon'').", "Petroleum exploitation has fallen since 1986, but this is still a substantial sector such that dips in prices have a strong effect on the economy.", "Rapids and waterfalls obstruct the southern rivers, but these sites offer opportunities for hydroelectric development and supply most of Cameroon's energy.", "The Sanaga River powers the largest hydroelectric station, located at Edéa.", "The rest of Cameroon's energy comes from oil-powered thermal engines.", "Much of the country remains without reliable power supplies.Transport in Cameroon is often difficult.", "Only 6.6% of the roadways are tarred.", "Roadblocks often serve little other purpose than to allow police and gendarmes to collect bribes from travellers.", "Road banditry has long hampered transport along the eastern and western borders, and since 2005, the problem has intensified in the east as the Central African Republic has further destabilised.Douala seaportIntercity bus services run by multiple private companies connect all major cities.", "They are the most popular means of transportation followed by the rail service ''Camrail''.", "Rail service runs from Kumba in the west to Bélabo in the east and north to Ngaoundéré.", "International airports are located in Douala and Yaoundé, with a third under construction in Maroua.", "Douala is the country's principal seaport.", "In the north, the Bénoué River is seasonally navigable from Garoua across into Nigeria.Although press freedoms have improved since the first decade of the 21st century, the press is corrupt and beholden to special interests and political groups.", "Newspapers routinely self-censor to avoid government reprisals.", "The major radio and television stations are state-run and other communications, such as land-based telephones and telegraphs, are largely under government control.", "However, cell phone networks and Internet providers have increased dramatically since the first decade of the 21st century and are largely unregulated.Cameroon was ranked 123rd in the Global Innovation Index in 2023." ], [ "Demographics", "The population of Cameroon was in .", "The life expectancy was 62.3 years (60.6 years for males and 64 years for females).Cameroonian women on Women's Day CelebrationCameroon has slightly more women (50.5%) than men (49.5%).", "Over 60% of the population is under age 25.People over 65 years of age account for only 3.11% of the total population.Cameroon's population is almost evenly divided between urban and rural dwellers.", "Population density is highest in the large urban centres, the western highlands, and the northeastern plain.", "Douala, Yaoundé, and Garoua are the largest cities.", "In contrast, the Adamawa Plateau, southeastern Bénoué depression, and most of the South Cameroon Plateau are sparsely populated.According to the World Health Organization, the fertility rate was 4.8 in 2013 with a population growth rate of 2.56%.People from the overpopulated western highlands and the underdeveloped north are moving to the coastal plantation zone and urban centres for employment.", "Smaller movements are occurring as workers seek employment in lumber mills and plantations in the south and east.", "Although the national sex ratio is relatively even, these out-migrants are primarily males, which leads to unbalanced ratios in some regions.Musgum, in the Far North Region, are made of earth and grass.Both monogamous and polygamous marriage are practised, and the average Cameroonian family is large and extended.", "In the north, women tend to the home, and men herd cattle or work as farmers.", "In the south, women grow the family's food, and men provide meat and grow cash crops.", "Cameroonian society is male-dominated, and violence and discrimination against women is common.The number of distinct ethnic and linguistic groups in Cameroon is estimated to be between 230 and 282.The Adamawa Plateau broadly bisects these into northern and southern divisions.", "The northern peoples are ''Sudanic'' groups, who live in the central highlands and the northern lowlands, and the Fulani, who are spread throughout northern Cameroon.", "A small number of Shuwa Arabs live near Lake Chad.", "Southern Cameroon is inhabited by speakers of Bantu and Semi-Bantu languages.", "Bantu-speaking groups inhabit the coastal and equatorial zones, while speakers of Semi-Bantu languages live in the Western grassfields.", "Some 5,000 Gyele and Baka Pygmy peoples roam the southeastern and coastal rainforests or live in small, roadside settlements.", "Nigerians make up the largest group of foreign nationals.===Refugees===In 2007, Cameroon hosted approximately 97,400 refugees and asylum seekers.", "Of these, 49,300 were from the Central African Republic (many driven west by war), 41,600 from Chad, and 2,900 from Nigeria.", "Kidnappings of Cameroonian citizens by Central African bandits have increased since 2005.In the first months of 2014, thousands of refugees fleeing the violence in the Central African Republic arrived in Cameroon.On 4 June 2014, AlertNet reported:===Languages===upright=1.2The official percentage of French and English speakers by the Presidency of Cameroon is estimated to be 70% and 30% respectively.", "German, the language of the original colonisers, has long since been displaced by French and English.", "Cameroonian Pidgin English is the lingua franca in the formerly British-administered territories.", "A mixture of English, French, and Pidgin called Camfranglais has been gaining popularity in urban centres since the mid-1970s.In addition to the colonial languages, there are approximately 250 other languages spoken by nearly 20 million Cameroonians making Cameroon one of the most linguistically diverse countries in the world.In 2017, there were language protests by the anglophone population against perceived oppression by francophone speakers.", "The military was deployed against the protesters and people were killed, hundreds imprisoned and thousands fled the country.", "This culminated in the declaration of an independent Republic of Ambazonia, which has since evolved into the Anglophone Crisis.", "It is estimated that by June 2020, 740,000 people had been internally displaced as a result of this crisis.===Religion===Cameroon has a high level of religious freedom and diversity.", "The majority faith is Christianity, practised by about two-thirds of the population, while Islam is a significant minority faith, adhered to by about one-fourth.", "In addition, traditional faiths are practised by many.", "Muslims are most concentrated in the north, while Christians are concentrated primarily in the southern and western regions, but practitioners of both faiths can be found throughout the country.", "Large cities have significant populations of both groups.", "Muslims in Cameroon are divided into Sufis, Salafis, Shias, and non-denominational Muslims.Our Lady of Victories Cathedral, catholic church in YaoundéPeople from the North-West and South-West provinces, which used to be a part of British Cameroons, have the highest proportion of Protestants.", "The French-speaking regions of the southern and western regions are largely Catholic.", "Southern ethnic groups predominantly follow Christian or traditional African animist beliefs, or a syncretic combination of the two.", "People widely believe in witchcraft, and the government outlaws such practices.", "Suspected witches are often subject to mob violence.", "The Islamist jihadist group Ansar al-Islam has been reported as operating in North Cameroon.In the northern regions, the locally dominant Fulani ethnic group is almost completely Muslim, but the overall population is fairly evenly divided among Muslims, Christians, and followers of indigenous religious beliefs (called ''Kirdi'' (\"pagan\") by the Fulani).", "The Bamum ethnic group of the West Region is largely Muslim.", "Native traditional religions are practised in rural areas throughout the country but rarely are practised publicly in cities, in part because many indigenous religious groups are intrinsically local in character.===Education and health===School children in CameroonIn 2013, the total adult literacy rate of Cameroon was estimated to be 71.3%.", "Among youths age 15–24 the literacy rate was 85.4% for males and 76.4% for females.", "Most children have access to state-run schools that are cheaper than private and religious facilities.", "The educational system is a mixture of British and French precedents, with most instruction in English or French.Cameroon has one of the highest school attendance rates in Africa.", "Girls attend school less regularly than boys do because of cultural attitudes, domestic duties, early marriage, pregnancy, and sexual harassment.", "Although attendance rates are higher in the south, a disproportionate number of teachers are stationed there, leaving northern schools chronically understaffed.", "In 2013, the primary school enrollment rate was 93.5%.School attendance in Cameroon is also affected by child labour.", "Indeed, the United States Department of Labor Findings on the Worst Forms of Child Labor reported that 56% of children aged 5 to 14 were working children and that almost 53% of children aged 7 to 14 combined work and school.", "In December 2014, a ''List of Goods Produced by Child Labor or Forced Labor'' issued by the Bureau of International Labor Affairs mentioned Cameroon among the countries that resorted to child labor in the production of cocoa.upright=1.2The quality of health care is generally low.", "Life expectancy at birth is estimated to be 56 years in 2012, with 48 healthy life years expected.", "Fertility rate remains high in Cameroon with an average of 4.8 births per woman and an average mother's age of 19.7 years old at first birth.", "In Cameroon, there is only one doctor for every 5,000 people, according to the World Health Organization.", "In 2014, just 4.1% of total GDP expenditure was allocated to healthcare.", "Due to financial cuts in the health care system, there are few professionals.", "Doctors and nurses who were trained in Cameroon emigrate because in Cameroon the payment is poor while the workload is high.", "Nurses are unemployed even though their help is needed.", "Some of them help out voluntarily so they will not lose their skills.", "Outside the major cities, facilities are often dirty and poorly equipped.In 2012, the top three deadly diseases were HIV/AIDS, lower respiratory tract infection, and diarrheal diseases.", "Endemic diseases include dengue fever, filariasis, leishmaniasis, malaria, meningitis, schistosomiasis, and sleeping sickness.", "The HIV/AIDS prevalence rate in 2016 was estimated at 3.8% for those aged 15–49, although a strong stigma against the illness keeps the number of reported cases artificially low.", "46,000 children under age 14 were estimated to be living with HIV in 2016.In Cameroon, 58% of those living with HIV know their status, and just 37% receive ARV treatment.", "In 2016, 29,000 deaths due to AIDS occurred in both adults and children.Breast ironing, a traditional practice that is prevalent in Cameroon, may affect girls' health.", "Female genital mutilation (FGM), while not widespread, is practised among some populations; according to a 2013 UNICEF report, 1% of women in Cameroon have undergone FGM.", "Also impacting women and girls' health, the contraceptive prevalence rate is estimated to be just 34.4% in 2014.Traditional healers remain a popular alternative to evidence-based medicine." ], [ "Culture", "===Music and dance===Dancers greet visitors to the East Region.Music and dance are integral parts of Cameroonian ceremonies, festivals, social gatherings, and storytelling.", "Traditional dances are highly choreographed and separate men and women or forbid participation by one sex altogether.", "The dances' purposes range from pure entertainment to religious devotion.", "Traditionally, music is transmitted orally.", "In a typical performance, a chorus of singers echoes a soloist.Musical accompaniment may be as simple as clapping hands and stamping feet, but traditional instruments include bells worn by dancers, clappers, drums and talking drums, flutes, horns, rattles, scrapers, stringed instruments, whistles, and xylophones; combinations of these vary by ethnic group and region.", "Some performers sing complete songs alone, accompanied by a harplike instrument.Popular music styles include ambasse bey of the coast, assiko of the Bassa, mangambeu of the Bangangte, and tsamassi of the Bamileke.", "Nigerian music has influenced Anglophone Cameroonian performers, and Prince Nico Mbarga's highlife hit \"Sweet Mother\" is the top-selling African record in history.The two most popular music styles are makossa and bikutsi.", "Makossa developed in Douala and mixes folk music, highlife, soul, and Congo music.", "Performers such as Manu Dibango, Francis Bebey, Moni Bilé, and Petit-Pays popularised the style worldwide in the 1970s and 1980s.", "Bikutsi originated as war music among the Ewondo.", "Artists such as Anne-Marie Nzié developed it into a popular dance music beginning in the 1940s, and performers such as Mama Ohandja and Les Têtes Brulées popularised it internationally during the 1960s, 1970s and 1980s.===Holidays===The most notable holiday associated with patriotism in Cameroon is National Day, also called Unity Day.", "Among the most notable religious holidays are Assumption Day, and Ascension Day, which is typically 39 days after Easter.", "In the Northwest and Southwest provinces, collectively called Ambazonia, October 1 is considered a national holiday, a date Ambazonians consider the day of their independence from Cameroon.===Cuisine===Plantains and \"Bobolo\" (made from cassava) served with Ndolè (meat and shrimp)Cuisine varies by region, but a large, one-course, evening meal is common throughout the country.", "A typical dish is based on cocoyams, maize, cassava (manioc), millet, plantains, potatoes, rice, or yams, often pounded into dough-like fufu.", "This is served with a sauce, soup, or stew made from greens, groundnuts, palm oil, or other ingredients.", "Meat and fish are popular but expensive additions, with chicken often reserved for special occasions.", "Dishes are often quite spicy; seasonings include salt, red pepper sauce, and maggi.Cutlery is common, but food is traditionally manipulated with the right hand.", "Breakfast consists of leftovers of bread and fruit with coffee or tea.", "Generally, breakfast is made from wheat flour in various different foods such as puff-puff (doughnuts), accra banana made from bananas and flour, bean cakes, and many more.", "Snacks are popular, especially in larger towns where they may be bought from street vendors.===Fashion===Cameroonian fashion is varied and often mixes modern and traditional elements.", "Note the wearing of sun glasses, monk shoes, sandals, and a Smartwatch.Cameroon's relatively large and diverse population is likewise diverse in its fashions.", "Climate, religious, ethnic and cultural beliefs, and the influences of colonialism, imperialism, and globalization are all factors in contemporary Cameroonian dress.Notable articles of clothing include: Pagnes, sarongs worn by Cameroon women; Chechia, a traditional hat; kwa, a male handbag; and Gandura, male custom attire.Wrappers and loincloths are used extensively by both women and men but their use varies by region, with influences from Fulani styles more present in the north and Igbo and Yoruba styles more often in the south and west.Imane Ayissi is one of Cameroon's top fashion designers and has received international recognition.===Local arts and crafts===A woman weaves a basket near Lake Ossa, Littoral Region.", "Cameroonians practise such handicrafts throughout the country.Traditional arts and crafts are practised throughout the country for commercial, decorative, and religious purposes.", "Woodcarvings and sculptures are especially common.", "The high-quality clay of the western highlands is used for pottery and ceramics.", "Other crafts include basket weaving, beadworking, brass and bronze working, calabash carving and painting, embroidery, and leather working.", "Traditional housing styles use local materials and vary from temporary wood-and-leaf shelters of nomadic Mbororo to the rectangular mud-and-thatch homes of southern peoples.", "Dwellings of materials such as cement and tin are increasingly common.", "Contemporary art is mainly promoted by independent cultural organizations (Doual'art, Africréa) and artist-run initiatives (Art Wash, Atelier Viking, ArtBakery).===Literature===Cameroonian literature has concentrated on both European and African themes.", "Colonial-era writers such as Louis-Marie Pouka and Sankie Maimo were educated by European missionary societies and advocated assimilation into European culture to bring Cameroon into the modern world.", "After World War II, writers such as Mongo Beti and Ferdinand Oyono analysed and criticised colonialism and rejected assimilation.===Media===*Cameroon Radio Television===Films and literature===Shortly after independence, filmmakers such as Jean-Paul Ngassa and Thérèse Sita-Bella explored similar themes.", "In the 1960s, Mongo Beti, Ferdinand Léopold Oyono and other writers explored postcolonialism, problems of African development, and the recovery of African identity.", "In the mid-1970s, filmmakers such as Jean-Pierre Dikongué Pipa and Daniel Kamwa dealt with the conflicts between traditional and postcolonial society.", "Literature and films during the next two decades focused more on wholly Cameroonian themes.===Sports===Cameroon faces Germany at Zentralstadion in Leipzig, 17 November 2004National policy strongly advocates sport in all forms.", "Traditional sports include canoe racing and wrestling, and several hundred runners participate in the Mount Cameroon Race of Hope each year.", "Cameroon is one of the few tropical countries to have competed in the Winter Olympics.Sport in Cameroon is dominated by football.", "Amateur football clubs abound, organised along ethnic lines or under corporate sponsors.", "The national team has been one of the most successful in Africa since its strong showing in the 1982 and 1990 FIFA World Cups.", "Cameroon has won five African Cup of Nations titles and the gold medal at the 2000 Olympics.Cameroon was the host country of the Women Africa Cup of Nations in November–December 2016, the 2020 African Nations Championship and the 2021 Africa Cup of Nations.", "The women's football team is known as the \"Indomitable Lionesses\", and like their men's counterparts, are also successful at international stage, although it has not won any major trophy.Cricket has also entered into Cameroon as an emerging sport with the Cameroon Cricket Federation participating in international matches Cameroon has produced multiple National Basketball Association players including Pascal Siakam, Joel Embiid, D. J.", "Strawberry, Ruben Boumtje-Boumtje, Christian Koloko, and Luc Mbah a Moute.The former UFC Heavyweight Champion Francis Ngannou hails from Cameroon." ], [ "See also", "* Index of Cameroon-related articles* Outline of Cameroon* Telephone numbers in Cameroon===Notes===" ], [ "References", "===Citations======Sources===* * * * *" ], [ "Further reading", "* .", "Reporters without Borders.", "Retrieved 6 April 2007.", "* .", "''Human Development Report 2006''.", "United Nations Development Programme.", "Retrieved 6 April 2007.", "* * Fonge, Fuabeh P. (1997).", "''Modernization without Development in Africa: Patterns of Change and Continuity in Post-Independence Cameroonian Public Service''.", "Trenton, New Jersey: Africa World Press, Inc.* MacDonald, Brian S. (1997).", "\"Case Study 4: Cameroon\", ''Military Spending in Developing Countries: How Much Is Too Much?''", "McGill-Queen's University Press.", "* Njeuma, Dorothy L. (no date). \"", "Country Profiles: Cameroon\".", "The Boston College Center for International Higher Education.", "Retrieved 11 April 2008.", "* Rechniewski, Elizabeth.", "\"1947: Decolonisation in the Shadow of the Cold War: the Case of French Cameroon.\"", "''Australian & New Zealand Journal of European Studies'' 9.3 (2017).", "online* Sa'ah, Randy Joe (23 June 2006). \"", "Cameroon girls battle 'breast ironing'\".", "''BBC News''.", "Retrieved 6 April 2007.", "* Wright, Susannah, ed.", "(2006).", "''Cameroon''.", "Madrid: MTH Multimedia S.L.", "* \" World Economic and Financial Surveys\".", "World Economic Outlook Database, International Monetary Fund.", "September 2006.Retrieved 6 April 2007." ], [ "External links", "* Cameroon.", "''The World Factbook''.", "Central Intelligence Agency.", "* Cameroon Corruption Profile from Business Anti-Corruption Portal* Cameroon from ''UCB Libraries GovPubs''* * Cameroon profile from the BBC News* * Key Development Forecasts for Cameroon from International Futures;Government* Presidency of the Republic of Cameroon* Prime Minister's Office* National Assembly of Cameroon* Global Integrity Report: Cameroon has reporting on anti-corruption in Cameroon* Chief of State and Cabinet Members;Trade* Summary Trade Statistics from World Bank" ] ]

[ [ "History of Cameroon" ], [ "Introduction", "At the crossroads of West Africa and Central Africa, the territory of what is now '''Cameroon''' has seen human habitation since some time in the Middle Paleolithic, likely no later than 130,000 years ago.", "The earliest discovered archaeological evidence of humans dates from around 30,000 years ago at Shum Laka.", "The Bamenda highlands in western Cameroon near the border with Nigeria are the most likely origin for the Bantu peoples, whose language and culture came to dominate most of central and southern Africa between 1000 BCE and 1000 CE.European traders arrived in the fifteenth century and Cameroon was the exonym given by the Portuguese to the Wouri river, which they called ''Rio dos Camarões—''\"river of shrimps\" or \"shrimp river\", referring to the then-abundant Cameroon ghost shrimp.", "Cameroon was a source of slaves for the slave trade.", "While the northern part of Cameroon was subject to influence from the Islamic kingdoms in the Chad basin and the Sahel, the south was largely ruled by small kings, chieftains, and fons.Cameroon as a political entity emerged from the colonization of Africa by Europeans.", "From 1884, Cameroon was a German colony, German Kamerun, with its borders drawn through negotiations between the Germans, British, and French.", "After the First World War, the League of Nations mandated France to administer most of the territory, with the United Kingdom administering a small portion in the west.", "Following World War II, the League of Nations' successor, the United Nations, instituted a Trusteeship system, leaving France and Britain in control of their respective regions, French Cameroon and British Cameroon.", "In 1960, Cameroon became independent with part of British Cameroons voting to join former French Cameroon.", "Cameroon has had only two presidents since independence and while opposition parties were legalized in 1990 only one party has ever governed.", "Cameroon has maintained close relations with France and allied itself largely with Western political and economic interests throughout the Cold War and into the twenty-first century.", "This consistency gave Cameroon a reputation as one of the most stable countries in the region.", "In 2017, tensions between Anglophone Cameroonians in former British territory and the Francophone-dominated government led to an ongoing civil war known as the Anglophone Crisis in the west of the country, while Islamist insurgents Boko Haram continue to carry out military and terror attacks in the north of the country.In January 2024, Cameroon launched the world's first routine malaria vaccine program, using the World Health Organization (WHO)-approved RTS,S vaccine developed by British drugmaker GSK.", "The initiative aims to save thousands of African children's lives annually.", "Despite some skepticism, health experts emphasize careful community outreach to combat vaccine hesitancy and stress the importance of using existing preventive measures alongside vaccines." ], [ "Pre-colonial history", "===Prehistory===Terracotta Sao statuetteMap showing the approximate extent of the Sokoto Caliphate in 1875 as well as the remnants of the Kanem-Bornu empireMap of pre-colonial Cameroon coastline published in 1884Archaeological research has been relatively scarce in Cameroon due to a lack of resources and transportation infrastructure.", "Historically the warm, wet climate in many parts of the country was thought of as inhospitable to the preservation of remains, but recent finds and the introduction of new techniques have challenged that assumption.", "Evidence from digs at Shum Laka in the Northwest Region shows human occupation dating back 30,000 years while in the dense forests of the south, the oldest evidence of occupation is around 7000 years old.", "Recent research in southern Cameroon indicates that the Iron Age may have started there as early as 1000 BCE and was certainly well established by 100 BCE at the latest.Linguistic analysis, supported by archaeological and genetic research, has shown that the Bantu expansion, a series of migrations that spread Bantu culture across much of Sub-Saharan Africa, most likely originated in the highlands on the Nigeria-Cameroon border around 1000 BCE.", "Bantu languages spread with these people along with agricultural methods and possibly iron tools, first east and then south, forming one of the largest language families in Africa.", "In Cameroon, Bantu people largely displaced Central African Pygmies such as the Baka, who were hunter-gatherers and who now survive in much smaller numbers in the heavily forested southeast.", "Despite Cameroon being the original homeland of the Bantu people, the great medieval Bantu-speaking kingdoms arose elsewhere, such as what is now Kenya, Congo, Angola, and South Africa.===Northern Cameroon===The earliest known civilization to have left clear traces of their presence in the territory of modern Cameroon is known as the Sao civilisation.", "Known for their elaborate terracotta and bronze artwork and round, walled settlements in the Lake Chad Basin, little else is known with any certainty due to the lack of historical records.", "The culture possibly arose as early as the fourth century BC but certainly, by the end of the first millennium BC, their presence was well established around Lake Chad and near the Chari River.", "The city-states of the Sao reached their apex sometime between the ninth and fifteenth centuries AD.", "The Sao were displaced or assimilated by the sixteenth century.After the Muslim conquest of North Africa in 709, Islam's influence began to spread south with the growth of trans-Saharan trade, including in what is now northern Cameroon.", "The Kanem-Bornu Empire began in what is now Chad and likely came into conflict with the Sao.", "The Kanem Empire began in Chad in the eighth century and gradually extended its influence northward into Libya and southward into Nigeria and Cameroon.", "Slaves from raids in the south were their principal trade good along with mined salt.", "The Empire was Muslim from at least the eleventh century and reached its first peak in the 13th, controlling most of what is now Chad and smaller regions in surrounding countries.", "After a period of internal instability, the center of power shifted to Bornu with its capital at Ngazargamu, in what is now northwestern Nigeria, and territory was gradually reconquered and new territory in present-day Niger also conquered.", "The Empire began to decline in the seventeenth century though it continued to control much of northern Cameroon.From 1804 to 1808 the Fulani War saw the Bornu pushed north out of Cameroon and the Sokoto Caliphate took control of the region, as well as most of northern Nigeria and large swathes of Niger and Mali.", "A feudal empire with local rulers pledging allegiance and paying tributes to the Caliph, northern Cameroon was likely part of the Adamawa Emirate within the Caliphate.", "This structure proved susceptible to exploitation by colonial powers beginning in the 1870s, who sought to undermine local rulers' ties to the Caliphate.===Southern Regions===The Muslim empires of the Sahara and Sahel never reached further south than the highlands of the Cameroon Line.", "Further south, there is little archaeological evidence of large empires or kingdoms and no historical record due to the lack of writing in the region.", "When the Portuguese arrived in the region in the sixteenth century, a large number of kings, chiefs, and fons ruled small territories.", "Many ethnic groups, particularly speakers of the Grassfields languages in the west, have oral histories of migrating south fleeing Muslim invaders, likely reference to the Fulani War and subsequent conflicts in Nigeria and northern Cameroon.Malaria prevented significant European settlement or exploration until the late 1870s, when large supplies of the malaria suppressant quinine became available.", "The early European presence in Cameroon was primarily devoted to coastal trade and the acquisition of slaves.", "The Cameroon coast was a major hub for the purchase of slaves who were taken across the Atlantic to Brazil, the United States, and the Caribbean.", "In 1807, the British abolished slavery in the Empire and began military efforts to suppress the slave trade, particularly in West Africa.", "Combined with the end of legal slave imports in the United States the same year, the international slave trade in Cameroon declined sharply.", "Christian missionaries established a presence in the late nineteenth century.", "Around this time, the Aro Confederacy, was expanding its economic and political influence from southeastern Nigeria into western Cameroon.", "However, the arrival of British and German colonizers cut short its growth and influence." ], [ "Colonial Period", "The German corvette SMS OLGA bombarding Hickorytown (now Douala in December 1884'''Cameroon over time'''German Settlers celebrating Christmas in Kamerun===Scramble for Africa and German Kamerun (1884-1918)===The Scramble for Africa beginning in the late 1870s, saw European powers, primarily seeking to establish formal control over the parts of Africa not yet colonized.", "The Cameroon coast was of interest to both the British, already established in what is now Nigeria and with missionaries outposts in several towns, and the Germans who had extensive trading relationships and plantations established in the Douala region.", "On July 5, 1884, German explorer and administrator Gustav Nachtigal began signing agreements with Duala leaders establishing a German protectorate in the region.", "A brief conflict ensued with rival Duala chiefs which Germany and its allies won, leaving the British with little choice but to acknowledge Germany's claim to the region.", "The borders of modern Cameroon were established through a series of negotiations with the British and French.", "Germany established an administration for the colony with a capital first at Buea and later at Yaoundé and continued to explore the interior and co-opt or subjugate local rulers.", "The largest conflicts were the Bafut Wars and the Adamawa Wars which ended by 1907 with German victories.Germany was particularly interested in Cameroon's agricultural potential and entrusted large firms with the task of exploiting and exporting it.", "German Chancellor Otto von Bismarck defined the order of priorities as follows: \"first the merchant, then the soldier\".", "It was under the influence of a businessman Adolph Woermann, whose company set up a trading house in Douala, that Bismarck, initially skeptical about the interest of the colonial project, was convinced.", "Large German trading companies (Woermann, Jantzen & Thormählen) and concession companies (Südkamerun Gesellschaft, Nord-West Kamerun Gesellschaft) established themselves massively in the colony.", "Letting the big companies impose their order, the administration simply supported them, protected them, and tried to eliminate indigenous rebellions.The Imperial German government made substantial investments in the infrastructure of Cameroon, including the extensive railways, such as the 160-metre single-span railway bridge on the southern branch of Sanaga River.", "However, the indigenous peoples proved reluctant to work on these projects, so the Germans instigated a harsh and unpopular system of forced labour.", "In fact, Jesko von Puttkamer was relieved of duty as governor of the colony due to his untoward actions toward the native Cameroonians.", "In 1911 at the Treaty of Fez after the Agadir Crisis, France ceded a nearly 300,000 km2 portion of the territory of French Equatorial Africa to Kamerun which became Neukamerun (New Cameroon), while Germany ceded a smaller area in the north in present-day Chad to France.Shortly after the outbreak of World War I in 1914, the British invaded Cameroon from Nigeria and the French from French Equatorial Africa in the Kamerun campaign.", "The last German fort in the country surrendered in February 1916.After the Allied victory, the territory was partitioned between the United Kingdom and France, which was formalized on June 28, 1919, with League of Nations mandates (Class B).", "France gained the larger geographical share, transferred Neukamerun back to neighboring French colonies, and ruled the rest from Yaoundé as Cameroun (French Cameroons).", "Britain's territory, a strip bordering Nigeria from the sea to Lake Chad, with a roughly equal population was ruled from Lagos as part of Nigeria, known as Cameroons (British Cameroons).===French Cameroon (1918-1960)=======League of Nations Mandate, Free France, and UN Trust Territory====French Missionary with the Sultan of Ngaoundéré in 1920The French administration declined to return much of the property in Cameroon to its prior German owners, reassigning much of it to French companies.", "This was particularly the case for the Société financière des Caoutchoucs, which obtained plantations put into operation during the German period and became the largest company in French Cameroon.", "Roads and other infrastructure projects were undertaken with native labor, often in extremely harsh conditions.", "The Douala-Yaoundé railway line, begun under the German regime, was completed.", "Thousands of workers were forcibly deported to this site to work fifty-four hours a week.", "Workers also suffered from lack of food and the massive presence of mosquitoes and related illnesses.", "In 1925, the mortality rate on the site was 61.7%.", "However, the other sites were not as deadly, although working conditions were generally very harsh.French Cameroon joined the Free France in August 1940.The system established by Free France was essentially a military dictatorship.", "Philippe Leclerc de Hauteclocque established a state of siege throughout the country and abolished almost all public freedom.", "The objective was to neutralize any potential feelings of independence or sympathy for the former German colonizer.", "Indigenous people known for their Germanophilia were executed in public places.", "In 1945, the country was placed under the supervision of the United Nations, as successor to the League of Nations, which left Cameroon under French control as a UN Trust Territory.====Independence Movement====The leaders of the UPCIn 1948, the Union des populations du Cameroun (UPC), a nationalist movement, was founded and Ruben Um Nyobe took over as its leader.", "In May 1955, the arrests of independence activists were followed by riots in several cities across the country.", "The repression caused several dozen or hundreds of deaths - the French administration officially lists twenty-two, although secret reports acknowledge many more.", "The UPC was banned and nearly 800 of its activists were arrested, many of whom would be beaten in prison.", "Because they were wanted by the police, UPC activists took refuge in the forests, where they formed guerilla bands; they also took refuge in neighboring British Cameroon.", "The French authorities repressed these events and made arbitrary arrests.", "The party received the support of personalities such as Gamal Abdel Nasser and Kwame Nkrumah and France's action was denounced at the UN by representatives of countries such as India, Syria, and the Soviet Union.An insurrection broke out among the Bassa people on 18 to 19 December 1956.Several dozen anti-UPC figures were murdered or kidnapped, bridges, telephone lines, and other infrastructure were sabotaged.", "The French military and native security forces violently repressed these uprisings, which led to many native Cameroonians joining the cause of independence and long-running guerilla war.", "Several UPC militias were formed though their access to weapons was very limited.", "Though the UPC was a multi-ethnic movement, the pro-independence movement was seen as particularly strong among the Bamileke and Bassa peoples, and both were targeted by the French for severe repression, including razing of villages, forced relocations, and indiscriminate killings in what was sometimes called the Bamileke War or the Cameroon Independence War.", "Though the uprising was suppressed, guerilla violence and reprisals continued even after independence.Legislative elections were held on 23 December 1956 and the resulting Assembly passed a decree on 16 April 1957 which made French Cameroon a state.", "It took back its former status of associated territory as a member of the French Union.", "Its inhabitants became Cameroonian citizens, and Cameroonian institutions were created under a parliamentary democracy.", "On 12 June 1958, the Legislative Assembly of French Cameroon asked the French government to: \"Accord independence to the State of Cameroon at the ends of their trusteeship.", "Transfer every competence related to the running of internal affairs of Cameroon to Cameroonians\".", "On 19 October 1958, France recognized the right of its United Nations trust territory to choose independence.", "On 24 October 1958, the Legislative Assembly of French Cameroon solemnly proclaimed the desire of Cameroonians to see their country accede full independence on 1 January 1960.It enjoined the government of French Cameroon to ask France to inform the General Assembly of the United Nations, to abrogate the trusteeship accord concomitant with the independence of French Cameroon.On 12 November 1958, France asked the United Nations to grant French Cameroon independence and end the Trusteeship.", "On 5 December 1958, the United Nations’ General Assembly took note of the French government's declaration according to which French Cameroon would gain independence on 1 January 1960.On 13 March 1959, the United Nations’ General Assembly resolved that the UN Trusteeship Agreement with France for French Cameroon would end when French Cameroon became independent on 1 January 1960.===British Cameroons (1918-1961)=======Nigerian Administration====Dr.", "Endeley (first row, third from right) in BamendaThe British territory was administered as two areas, Northern Cameroons and Southern Cameroons.", "Northern Cameroons consisted of two non-contiguous sections, divided by a point where the Nigerian and Cameroon borders met and were governed as part of the Northern Region of Nigeria.", "Southern Cameroons was administered as a province of Eastern Nigeria.", "In British Cameroons, many German administrators were allowed to run the plantations of the southern coastal area after World War I.", "A British parliamentary publication, ''Report on the British Sphere of the Cameroons'' (May 1922, p. 62-8), reported that the German plantations there were \"as a whole .", ".", ".", "wonderful examples of industry, based on solid scientific knowledge.", "The natives have been taught discipline and have come to realize what can be achieved by industry.", "Large numbers who return to their villages take up cocoa or other cultivation on their own account, thus increasing the general prosperity of the country.\"", "In the 1930s, most of the white population still consisted of Germans, most of whom were interned in British camps starting in June 1940.The native population showed little interest in volunteering for the British forces during World War II; only 3,500 men did so.When the League of Nations ceased to exist in 1946, British Cameroons was reclassified as a UN trust territory, administered through the UN Trusteeship Council, but remained under British control.", "The United Nations approved the Trusteeship Agreements for British Cameroons to be governed by Britain on June 12, 1946.====Plebiscite and Independence====French Cameroun became independent, as Cameroun or Cameroon, in January 1960, and Nigeria was scheduled for independence later that same year, which raised the question of what to do with the British territory.", "After some discussion (which had been going on since 1959), a plebiscite was agreed to and held on 11 February 1961.The Muslim-majority Northern area opted for union with Nigeria, and the Southern area voted to join Cameroon." ], [ "Independence and the Ahidjo era (1960-1982)", "Cameroonian President Ahidjo meets U.S. President John Kennedy in 1962Reunification Monument in YaoundéFrench Cameroon achieved independence on January 1, 1960.After Guinea, it was the second of France's colonies in Sub-Saharan Africa to become independent.", "On 21 February 1960, the new nation held a constitutional referendum, approving a new constitution.", "On 5 May 1960, Ahmadou Ahidjo became president.", "Ahidjo aligned himself closely with France and allowed many French advisers and administrators to stay on as well as leaving most of the country's assets in the hands of French companies.===Union with Southern Cameroons===On 12 February 1961, the results of the Southern Cameroon plebiscite were announced and it was learned that Southern Cameroons had voted for unification with the Republic Of Cameroon, sometimes called \"reunification\" since both regions had been part of German Kamerun.", "To negotiate the terms of this union, the Foumban Conference was held on 16–21 July 1961.John Ngu Foncha, the leader of the Kamerun National Democratic Party and the Southern Cameroons elected government represented Southern Cameroons while Ahidjo represented Cameroon.", "The agreement reached was a new constitution, based heavily on the version adopted in Cameroon earlier that year, but with a federal structure granting former British Cameroons - now West Cameroon - jurisdiction over certain issues and procedural rights.", "Buea became the capital of West Cameroon while Yaounde doubled as the federal capital and East Cameroonian capital.", "Neither side was particularly satisfied as Ahidjo had wanted a unitary or more centralized state while the West Cameroonians had wanted more explicit protections.", "On 14 August 1961, the federal constitution was adopted, with Ahidjo as president.", "Foncha became the prime minister of West Cameroon and vice president of the Federal Republic of Cameroon.", "The unification of British and French Cameroon has caused linguistic and cultural tensions within Cameroon, which has led to violence.===Civil War and repression===The UPC, which had demanded a full break with France and many of whom espoused Marxist or other leftist ideologies, were not satisfied with Ahidjo's rule and close cooperation with the French and did not lay down their arms at independence and sought to overthrow Ahidjo's regime which they viewed as too subservient to France and some, but not all, espoused overtly Marxist views.", "Ahidjo requested continued French assistance in suppressing the UPC rebels in what became known as the Bamileke War after the region where much of the fighting took place.", "The UPC was ultimately defeated with government forces capturing the last important rebel leader in 1970.During the intervening years, Ahidjo used emergency powers granted due to the war and the fear of further ethnic conflict to centralize power in himself.", "He implemented a highly centralized and authoritarian government that used arbitrary police custody, prohibition of meetings and rallies, submission of publications to prior censorship, restriction of freedom of movement through the establishment of passes or curfews, and a prohibition on trade unions to prevent opposition.", "Anyone accusation of \"compromising public safety\" was handled outside traditional criminal process - without the right to a lawyer or any appeal.", "Sentences of life imprisonment at hard labor or death were numerous and executions were often public.In 1966, opposition parties were banned and Cameroon became a one-party state.", "On 28 March 1970 Ahidjo was re-elected as president with 100% of the vote and 99.4% turnout.", "Solomon Tandeng Muna became vice president.", "In 1972, a referendum was held on a new constitution, which replaced the federation between East and West with a unitary state called the '''United Republic of Cameroon''' and further expanded the power of the president.", "Official results claimed 98.2% turnout and 99.99% of votes in favor of the new constitution.", "Although Ahidjo's rule was authoritarian, he was seen as noticeably lacking in charisma in comparison to many post-colonial African leaders.", "He didn't follow the anti-western policies pursued by many of these leaders, which helped Cameroon achieve a degree of comparative political stability, retain Western investment, and see fairly steady economic growth.===Discovery of oil===Cameroon became an oil-producing country in 1977.The accounting of oil revenues was totally opaque and many Cameroonians felt the money was mismanaged or embezzled since.", "Oil remains a primary driver of the economy, though the country is not as oil-dependent as many other producers in the region." ], [ "Biya Era (1982-)", "Paul Biya with U.S. President Ronald Reagan in 1986On 30 June 1975, Paul Biya, a long-serving bureaucrat and administrator in the Ahidjo government, was appointed Prime Minister.", "On November 4, 1982, Ahidjo resigned as president and Biya was his legal successor.", "Many observers were surprised, as Biya is a Christian from the south while Ahidjo was a Muslim from the North and Ahidjo was only 59 years old.", "However, Ahidjo did not resign his role as leader of the governing party, and many speculated that he hoped Biya would be a figurehead, or perhaps even a temporary caretaker, as Ahidjo was rumored to be ill and receiving medical care in France.===Rift and coup attempt===Despite previous good relations, in 1983 a rift was apparent between Biya and Ahidjo.", "Ahidjo left for France and publicly accused Biya of abuse of power.", "Ahidjo sought to use his continuing control over the party apparatus to sideline Biya, by causing the party, not the President to set the government's agenda.", "However, at the party conference in September, Biya was elected to lead the party and Ahidjo resigned.", "In January 1984, Biya was elected president of the country, running unopposed.", "In February, two senior officials were arrested and, along with Ahidjo who was tried ''in absentia'' alongside them.On April 6, 1984, supporters of Ahidjo attempted a coup d'état, led by the Republican Guard, an elite force recruited by Ahidjo, mainly from the north.", "The Republican Guard under Colonel Saleh Ibrahim took control of the Yaounde airport, national radio station, and other key points around the capital.", "However, Biya was able to hole up in the presidential palace with his bodyguard until troops from outside the capital were able to retake control within two days.", "Ahidjo denied knowledge or responsibility for the coup attempt but was widely viewed as behind it.===Limnic eruptions===Lake MonounOn August 15, 1984, Lake Monoun exploded in a limnic eruption that released enormous amounts of carbon dioxide, suffocating 37 people to death.", "On August 21, 1986, another limnic eruption at Lake Nyos killed as many as 1,800 people and 3,500 livestock.", "The two disasters are the only recorded instances of limnic eruptions, though geologic and sedimentary evidence indicates they may have caused large localized die-offs before historical records began.===Brief political loosening===Biya had initially seemed supportive of loosening restrictions on civil society, but the coup attempt ended any sign of opening up.", "However, by 1990, pressure from Western governments was mounting as the end of the Cold War made them less tolerant of authoritarian allies.", "In December 1990, opposition parties were legalized for the first time since 1966.The first multiparty elections were held in 1992 and were hotly contested.", "Biya won with 40% of the vote against 36 for his closest competitor and 19 for another opposition party.", "In Parliament, Biya's ruling party on a plurality with 45% of the votes but failed to obtain a majority.", "The competitiveness of the election was not to Biya's liking and subsequent elections have been widely criticized by opposition parties and international observers as rigged and suffering from numerous and widespread irregularities.", "The ruling party has had no trouble gaining large majorities.Pressure from Anglophone groups in former British Cameroons resulted in changes to the constitution in 1996, which purported to decentralize power but fell short of Anglophone demands to reestablish the federal structure.", "As a result of continued opposition, many of the changes adopted in 1996 have never been fully implemented and power remains highly centralized in the President.===Bakassi border conflict===Bakassi PeninsulaBakassi is a peninsula on the Gulf of Guinea between the Cross River estuary and the Rio del Rey estuary on the east.", "The area was administered by Nigeria through the colonial era.", "However, after independence, efforts to demarcate the border revealed that a 1913 agreement between Britain and Germany, placed Bakassi in German Cameroon and accordingly should belong to Cameroon.", "Nigeria pointed to other colonial-era documents and agreements and their long history of administration to object to this narrative.", "The competing claims grew contentious after oil was discovered in the region.", "An agreement between the two countries in 1975 was derailed by a coup in Nigeria.", "In 1981, clashes between Nigerian and Cameroonian forces resulted in several deaths and nearly led to war between the two nations.", "The border saw further clashes several times throughout the 1980s.", "In 1993, the situation worsened with both countries sending large military contingents to the region and numerous reports of skirmishes and attacks against civilians.", "On 29 March 1994, Cameroon referred the matter to the International Court of Justice (ICJ).In October 2002, the International Court of Justice ruled in favor of Cameroon.", "However, the ruling was resisted by Nigeria.", "Pressure from the UN and international community and the threat of withdrawal of foreign aid ultimately forced Nigeria to acquiesce and in 2006 the Greentree Agreement laid out a plan for the transfer of administration over two years.", "The transfer was successfully accomplished but many inhabitants of the peninsula retained their Nigerian citizenship and remain dissatisfied with the transition.", "Low-level violence continued until it was subsumed in the Anglophone Crisis in 2017.===2008 protests===In February 2008, Cameroon experienced widespread violent unrest as a strike by transport workers opposing high fuel prices and poor working conditions coincided with President Paul Biya's announcement that he wanted the constitution to be amended to remove term limits.", "Biya was scheduled to leave power at the end of his term in 2011.After several days of widespread rioting, looting, and reports of gunfire in all the major cities, calm was eventually restored after a crackdown with thousands arrested, and at least several dozen killed.", "The government announced lower fuel prices, increased wages for the military and civil servants, and decreased duties on key foodstuffs and construction materials.", "Many opposition groups reported additional harassment and restrictions on speech, gatherings, and political activity in the wake of the protests.", "Ultimately, the constitutional term limits were revoked and Biya was reelected in 2011 in an election criticized by the opposition and international observers as plagued by irregularities and low turnout." ], [ "Contemporary issues", "===Boko Haram===Map of Boko Haram impacted areas including northern CameroonIn 2014, the Boko Haram insurgency spread into Cameroon from Nigeria.", "In May 2014, in the wake of the Chibok schoolgirl kidnapping, Presidents Paul Biya of Cameroon and Idriss Déby of Chad announced they were waging war on Boko Haram, and deployed troops to the Northern Nigerian border.", "Cameroon announced in September 2018 that Boko Haram had been repelled, but the conflict persists in the northern border areas nonetheless.===Anglophone Crisis===Anglophone regions claimed by separatists as AmbazoniaIn November 2016, major protests broke out in the Anglophone regions of Cameroon.", "In September 2017, the protests and the government's response to them escalated into an armed conflict, with separatists declaring the independence of Ambazonia and starting a guerilla war against the Cameroonian Army." ], [ "Football", "Cameroon has received some international attention following the relative success of its football team.", "The team has qualified for the FIFA World Cup eight times, more than any other African team.", "However, the team has only made it out of the group stage once, in 1990, when they became the first African team to reach the quarter-final of the World Cup.", "They have also won five Africa Cup of Nations." ], [ "See also", "*Ambazonia*History of Africa*Politics of Cameroon*List of heads of government of Cameroon*List of heads of state of Cameroon* Douala history and timeline* Yaoundé history and timeline" ], [ "References", "* Background Note: Cameroon from the U.S. Department of State.", "* Bullock, A. L. C. (1939).", "''Germany's Colonial Demands'', Oxford University Press.", "* DeLancey, Mark W., and DeLancey, Mark Dike (2000): ''Historical Dictionary of the Republic of Cameroon'' (3rd ed.).", "Lanham, Maryland: The Scarecrow Press.", "* Schnee, Heinrich (1926).", "''German Colonization, Past and Future: The Truth about the German Colonies.''", "London: George Allen & Unwin." ], [ "Notes", "===Works cited===* * *" ], [ "Further reading", "* Ardener, Edwin.", "''Kingdom on Mount Cameroon: Studies in the history of the Cameroon Coast, 1500-1970'' (Berghahn Books, 1996) online.", "* Arnold, Stephen.", "\"Preface to a history of Cameroon literature in English.\"", "''Research in African Literatures'' 14.4 (1983): 498-515 online* Awasom, Nicodemus Fru.", "\"The reunification question in Cameroon history: was the bride an enthusiastic or a reluctant one?\"", "''Africa Today'' (2000): 91-119.exccerpt* DeLancey, Mark Dike, Mark W. DeLancey, and Rebecca Neh Mbuh.", "''Historical dictionary of the Republic of Cameroon'' (Rowman & Littlefield, 2019).", "online* Diduk, Susan.", "\"European alcohol, history, and the state in Cameroon.\"", "''African Studies Review'' 36.1 (1993): 1-42.doi.org/10.2307/525506* Dupraz, Yannick.", "\"French and British colonial legacies in education: Evidence from the partition of Cameroon.\"", "''Journal of Economic History'' 79.3 (2019): 628-668.online* Dze-Ngwa, Willibroad.", "\"The First World War and its aftermath in Cameroon: A historical evaluation of a centenary, 1914-2014.\"", "''International Journal of Liberal Arts and Social Science'' 3.2 (2015): 78-90.online* Fowler, Ian.", "\"Kingdoms of the Cameroon Grassfields.\"", "''Reviews in Anthropology'' 40.4 (2011): 292-311.", "* Fowler, Ian.", "\"Tribal and palatine arts of the Cameroon grassfields: elements for a ‘traditional’ regional identity.\"", "in ''Contesting Art'' (Routledge, 2020) pp.", "63-84.", "* Fowler, Ian, and Verkijika G. Fanso, eds.", "''Encounter, transformation and identity: peoples of the western Cameroon borderlands, 1891-2000'' (Berghahn Books, 2009) online.", "* Fowler, Ian, and David Zeitlyn, eds.", "''African Crossroads: intersections between history and anthropology in Cameroon'' Berghahn Books, 1996) online* Geschiere, Peter.", "\"Chiefs and colonial rule in Cameroon: Inventing chieftaincy, French and British style.\"", "''Africa'' 63.2 (1993): 151-175.", "* Mengang, Joseph Mewondo.", "\"Evolution of natural resource policy in Cameroon.\"", "''Yale F&ES Bulletin'' 102 (1998): 239-248.online* Njung, George N. \"The British Cameroons mandate regime: The roots of the twenty-first-century political crisis in Cameroon.\"", "''American Historical Review'' 124.5 (2019): 1715-1722." ], [ "External links", "*" ] ]

[ [ "Geography of Cameroon" ], [ "Introduction", "Map of CameroonLocation of CameroonAt , Cameroon is the world's 53rd largest country.", "It is slightly larger than the nation of Sweden and the US state of California.", "It is comparable in size to Papua New Guinea.", "Cameroon's landmass is , with of water.The country is located in Central and West Africa, bordering the Bight of Biafra, between Equatorial Guinea and Nigeria.Cameroon is sometimes described as \"Africa in miniature\" because it exhibits all the major climates and vegetation of the continent: mountains, desert, rain forest, savanna grassland, and ocean coastland.", "Cameroon can be divided into five geographic zones.", "These are distinguished by dominant physical, climatic, and vegetative features." ], [ "Natural regions", "Topography of CameroonNight view of Limbe Atlantic OceanMangroves along the banks of Wouri River in DoualaCameroon's coastal plain extends inland from the Gulf of Guinea (part of the Atlantic Ocean) to the edge of a plateau.", "In the former western state, however, the mass of Mount Cameroon reaches almost to the sea.", "The plain is densely forested including areas of Central African mangroves especially around Douala and in the estuary of the Cross River on the border with Nigeria.A recent global remote sensing analysis suggested that there were 643km² of tidal flats in Cameroon, making it the 39th ranked country in terms of tidal flat area.The low South Cameroon Plateau, rising from the coastal plain and dominated by tropical rain forest, has an average elevation of .", "It is less humid than the coast.In western Cameroon is an irregular chain of mountains, hills, and plateaus that extends from Mount Cameroon almost to Lake Chad at the northern tip of the country.", "This region includes the Bamenda, Bamiléké, and Mambilla highlands.", "It also contains some of the country's most fertile soils, notably around volcanic Mt.", "Cameroon.", "This area of tropical forest has been categorised by the World Wildlife Fund as the Cameroonian Highlands forests ecoregion with Mount Cameroon considered separately because as an active volcano it has a distinct environment from the other mountains.From the forested southern plateau the land rises northward to the grassy, rugged Adamaoua (Adamawa) highlands.", "Stretching across Cameroon from the western mountain area, the Adamaoua forms a barrier between the north and south.", "Its average elevation is .The southern savanna plain extends from the edge of the Adamaoua to Lake Chad.", "Its characteristic vegetation is scrub and grass.", "This is region of sparse rainfall and high median temperatures has been included as part of the East Sudanian savanna ecoregion." ], [ "Climate", " The climate varies with terrain, from tropical along the coast to semiarid and hot in the north.Exceedingly hot and humid, the coastal belt includes some of the wettest places on earth.", "For example, Debundscha, at the base of Mt.", "Cameroon, has an average annual rainfall of ." ], [ "Biodiversity", "The wide diversity of climates and natural regions of Cameroon, as coastline, mountains, savanna, deserts, and tropical forests, allows that the country counts with rich biodiversity.", "Twenty-two million hectares from the Congo Basin forest ecosystem are located in Cameroon, where 9,000 plant species, 900 bird species, and 320 mammals species live, included 156 endemic plants, eight endemic birds, and 14 endemic mammals.", "The border with Nigeria has one of the highest concentration of biodiversity in Africa.As part of the conservation efforts to protect threatened natural resources, Cameroon has established protected areas since 1932, included national parks, wildlife sanctuaries, faunal reserves, and one flora sanctuary.Cameroon had a 2018 Forest Landscape Integrity Index mean score of 8.00/10, ranking it 29th globally out of 172 countries." ], [ "Rivers", "Sanaga RiverMungo River with fishing Canoes at the far end of the pictureThe country has four patterns of drainage.", "In the south, the principal rivers flow southwestward or westward directly to the Gulf of Guinea – the Wouri, and lesser Dibamba, Bimbia and Mungo to the Cameroon estuary near Douala; Sanaga, Nyong, and Ntem further south along the coast; Akwayafe and Manyu (which joins Nigerian Cross), and the lesser Ndian and Meme north of the coast.", "The Dja and Kadeï, however, drain southeastward into the Congo River.", "In northern Cameroon, the Benoué River (Benue) runs north and west, eventually into the Niger, while the Logone River flows northward into Lake Chad.Some of the borders of Cameron follow rivers, including the Aïna, Akwayafe, and Ntem or Campo." ], [ "Data", "'''Location:'''Central Africa, bordering the Bight of Biafra, between Equatorial Guinea and Nigeria'''Geographic coordinates:''''''Continent:'''Africa'''Area:'''''total:''''land:''''water:'''''Area – comparative:'''slightly larger than Sweden'''Land boundaries:'''''total:''5,018 km''border countries:''Central African Republic 901 km, Chad 1,116 km, Republic of the Congo 494 km, Equatorial Guinea 183 km, Gabon 349 km, Nigeria 1,975 km'''Coastline:'''402 km'''Maritime claims:'''''territorial sea:'''''Terrain:'''diverse, with coastal plain in southwest, dissected plateau in center, mountains in west, plains in north'''Elevation extremes:'''''lowest point:''Atlantic Ocean 0 m''highest point:''Fako (on.", "Mt.", "Cameroon) 4,095 m'''Natural resources:'''petroleum, bauxite, iron ore, timber, hydropowerMount Cameroon craters'''Land use:'''''arable land:''13.12%''permanent crops:''3.28%''other:''83.61% (2012)'''Irrigated land:'''256.5 km2 (2003)Rhumsiki Peak in Cameroon's Far North Province.", "'''Total renewable water resources:'''285.5 km3 (2011)'''Freshwater withdrawal (domestic/industrial/agricultural):'''''total:''0.97 km3/yr (23%/10%/68%)''per capita:''58.9 m3/yr (2005)'''Natural hazards:'''Recent limnic eruptions with release of carbon dioxide:*from Lake Monoun, 15 August 1984, killing 37*from Lake Nyos, 21 August 1986, killing as many as 1,800'''Environment – current issues:'''water-borne diseases are prevalent; deforestation; overgrazing; desertification; poaching; overfishing'''Environment – international agreements:'''''party to:''Biodiversity, Climate Change, Desertification, Endangered Species, Hazardous Wastes, Law of the Sea, Ozone Layer Protection, Tropical Timber 83, Tropical Timber 94, Wetlands, Whaling''signed, but not ratified:''Nuclear Test Ban'''Geography – note:'''sometimes referred to as 'the hinge of Africa;' throughout the country there are areas of thermal springs and indications of current or prior volcanic activity; Mount Cameroon, the highest mountain in Sub-Saharan west Africa, is an active volcano220x220px" ], [ "Extreme points", "This is a list of the extreme points of Cameroon, the points that are farther north, south, east or west than any other location.", "* Northernmost point – unnamed peninsula jutting into Lake Chad, Far North Region* Easternmost point – unnamed location on the border with the Republic of Congo in the Sangha River opposite the Congolese town of Bomassa, East Region* Southernmost point – unnamed headland at the confluence on the Sangha River and the Ngoko River immediately north of the Congolese town of Ouesso, East Region* Westernmost point – unnamed point on Akwabana Island, Southwest Region" ], [ "Gallery", "File:Koppen-Geiger Map CMR present.svg|Cameroon map of Köppen climate classification.File:Hills near Ngaoundal.jpg|Countryside near Ngaoundal in Cameroon's Adamawa Region.File:Berges du Wouri 05.jpg|A view of Wouri River with a transport vessel in the Littoral Region of Cameroon" ], [ "See also", "*Cameroon*Geology of Cameroon*List of volcanoes in Cameroon" ], [ "Notes" ], [ "References" ] ]

[ [ "Demographics of Cameroon" ], [ "Introduction", " The '''demographic profile of Cameroon''' is complex for a country of its population.", "Cameroon comprises an estimated 250 distinct ethnic groups, which may be formed into five large regional-cultural divisions:* '''western highlanders''' ('''Semi-Bantu''' or '''grassfielders'''), including the Bamileke, Bamum (or ''Bamoun''), and many smaller Tikar groups in the Northwest (est.", "38% of total population);* '''coastal tropical forest peoples''', including the Bassa, Duala (or ''Douala''), and many smaller groups in the Southwest (12%);* '''southern tropical forest peoples''', including the Beti-Pahuin, Bulu (a subgroup of Beti-Pahuin), Fang (subgroup of Beti-Pahuin), Maka, Njem, and Baka pygmies (18%);* '''predominantly Islamic peoples''' of the northern semi-arid regions (the Sahel) and central highlands, including the Fulani ( or ''Peuhl''; ) (14%); ''and''* '''the \"Kirdi\"''', non-Islamic or recently Islamic peoples of the northern desert and central highlands (18%).", "113,000 Igbo people live in Cameroon.", "The Cameroon government held two national censuses during the country's first 44 years as an independent country, in 1976 and again in 1987.Results from the second head count were never published.", "A third census, expected to take years to produce results, began on November 11, 2005, with a three-week interviewing phase.", "It is one of a series of projects and reforms required by the International Monetary Fund as prerequisites for foreign debt relief.", "The first results were published in 2010.A Tikar family in the Northwest Province" ], [ "Population", "Population, fertility rate and net reproduction rate, United Nations estimatesAccording to the total population was in , compared to only 4 466 000 in 1950.The proportion of children below the age of 15 in 2010 was 40.6%, 55.9% was between 15 and 65 years of age, while 3.5% was 65 years or older.Total populationPopulation aged 0–14 (%)Population aged 15–64 (%)Population aged 65+ (%) 19504 466 00039.656.93.5 19554 901 00040.156.43.5 19605 409 00040.655.93.6 19656 049 00041.554.93.6 19706 842 00042.454.03.6 19757 838 00043.652.73.7 19809 110 00044.651.83.6 198510 519 00045.251.23.6 199012 181 00045.251.33.6 199513 940 00044.452.13.5 200015 678 00042.853.73.5 200517 554 00041.654.93.5 201019 599 00040.655.93.5Population Estimates by Sex and Age Group (01.I.2010) (Data refer to national projections.", "):Age GroupMaleFemaleTotal% Total 9 599 224 9 806 876 19 406 100 100 0–4 1 662 298 1 624 936 3 287 234 16.94 5–9 1 412 467 1 370 992 2 783 459 14.34 10–14 1 227 470 1 167 201 2 394 671 12.34 15–19 1 068 509 1 101 526 2 170 035 11.18 20–24 855 334 981 955 1 837 289 9.47 25–29 712 550 813 266 1 525 816 7.86 30–34 588 210 621 397 1 209 607 6.23 35–39 460 394 482 319 942 713 4.86 40–44 388 539 405 307 793 846 4.09 45–49 323 507 316 740 640 247 3.30 50–54 261 626 260 284 521 910 2.69 55–59 178 876 159 112 337 988 1.74 60–64 155 208 160 671 315 879 1.63 65-69 110 645 116 645 227 290 1.17 70-74 88 969 100 602 189 571 0.98 75-79 47 173 50 905 98 078 0.51 80-84 31 609 39 976 71 585 0.37 85-89 12 109 14 455 26 564 0.14 90-94 6 942 8 773 15 715 0.08 95+ 6 789 9 814 16 603 0.09Age group MaleFemaleTotalPercent 0–14 4 302 235 4 163 129 8 465 364 43.62 15–64 4 992 753 5 302 577 10 295 330 53.05 65+ 304 236 341 170 645 406 3.33Population Estimates by Sex and Age Group (01.VII.2019) (Source: Population projections and estimates of priority targets for the various health programs and interventions, National Institute of Statistics (2016).", "):Age GroupMaleFemaleTotal% Total 12 609 256 12 883 098 25 492 354 100 0–4 1 904 057 1 975 656 3 879 713 15.22 5–9 1 720 605 1 757 707 3 478 312 13.64 10–14 1 574 388 1 524 415 3 098 803 12.16 15–19 1 386 436 1 346 672 2 733 108 10.72 20–24 1 213 959 1 171 500 2 385 459 9.36 25–29 1 035 624 985 314 2 020 938 7.93 30–34 888 422 967 529 1 855 951 7.28 35–39 684 460 786 728 1 471 188 5.77 40–44 584 695 650 891 1 235 586 4.85 45–49 438 096 447 171 885 267 3.47 50–54 352 927 392 864 745 791 2.93 55–59 275 690 281 896 557 586 2.19 60–64 220 891 242 450 463 341 1.82 65-69 143 542 141 522 285 064 1.12 70-74 101 474 110 948 212 422 0.83 75-79 49 486 55 219 104 705 0.41 80+ 34 504 44 616 79 120 0.31Age group MaleFemaleTotalPercent 0–14 5 199 050 5 257 778 10 456 828 41.02 15–64 7 130 686 7 273 015 14 403 701 56.50 65+ 279 520 352 305 631 825 2.48===Fertility and births===Total Fertility Rate (TFR) (Wanted Fertility Rate) and Crude Birth Rate (CBR): Year CBR (Total) TFR (Total) CBR (Urban) TFR (Urban) CBR (Rural) TFR (Rural) 1991 39 5.82 (5.17) 5.17 (4.52) 6.29 (5.66) 1998 37.4 5.2 (4.6) 31.5 3.9 (3.4) 40.1 5.8 (5.3) 2004 37.8 5.0 (4.5) 34.9 4.0 (3.7) 40.5 6.1 (5.6) 2011 38.1 5.1 (4.5) 34.6 4.0 41.3 6.4 2018 36.8 4.8 (4.3) 32.9 3.8 (3.4) 40.7 6.0 (5.5)Fertility data as of 2011 (DHS Program): Region Total fertility rate Percentage of women age 15–49 currently pregnant Mean number of children ever born to women age 40–49Adamaoua 5.2 8.6 6.5Centre (except Yaoundé) 5.6 8.8 5.5Douala 3.2 8.1 4.5Est 5.4 12.0 5.6Extrême-Nord 6.8 14.8 7.3Littoral (except Douala) 4.6 8.4 5.1Nord 6.5 12.4 7.1Nord-Ouest 4.4 6.9 5.4Ouest 6.0 10.1 5.8Sud 4.6 9.6 5.2Sud-Ouest 4.0 7.6 5.5Yaoundé 3.5 6.5 4.4" ], [ "Vital statistics", "Registration of vital events is in Cameroon not complete.", "The Population Departement of the United Nations prepared the following estimates.YearMid-year populationLive birthsDeaths perNatural change CBR*CDR*NC*IMR*TFR*Life expectancy (years)19504 316 000  187 000  121 000  66 00043.228.115.2194.25.5434.461951  4 382 000  189 000  122 000  67 00043.227.915.2193.15.5234.641952  4 450 000  192 000  123 000  68 00043.027.715.4190.95.4935.011953  4 519 000  194 000  123 000  71 00043.027.315.6188.55.4735.431954  4 592 000  197 000  122 000  76 00042.926.516.5182.75.4736.421955  4 671 000  201 000  120 000  81 00043.025.717.3177.35.4737.361956  4 754 000  205 000  119 000  86 00043.125.018.1172.05.4938.351957  4 841 000  209 000  122 000  88 00043.325.118.2167.05.5138.261958  4 932 000  214 000  121 000  94 00043.524.519.0162.45.5539.101959  5 028 000  220 000  121 000  99 00043.724.019.8158.35.5939.841960  5 118 000  226 000  147 000  80 00044.228.615.5154.85.6534.821961  5 200 000  232 000  146 000  86 00044.728.216.5151.95.7135.411962  5 304 000  239 000 118 000  121 00045.122.322.8149.65.7742.521963  5 428 000  246 000  120 000  126 00045.322.023.3147.55.8342.921964  5 556 000  252 000  121 000  131 00045.421.823.6145.35.8943.311965  5 690 000  258 000  122 000  137 00045.421.424.0142.75.9543.891966  5 830 000  265 000  122 000  142 00045.421.024.4139.66.0044.441967  5 975 000  271 000  122 000  149 00045.320.424.9135.86.0645.181968  6 127 000  277 000  121 000  156 00045.219.825.4131.76.1145.981969  6 286 000  283 000  121 000  163 00045.119.225.9127.56.1446.821970  6 453 000  291 000  120 000  171 00045.118.626.5123.46.2047.581971  6 627 000  299 000  120 000  179 00045.118.127.0119.96.2648.251972  6 809 000  306 000  120 000  186 00045.017.627.3117.06.2848.901973  6 999 000  315 000  121 000  193 00044.917.327.6115.06.3149.321974  7 195 000  323 000  123 000  200 00044.917.127.7113.86.3449.571975  7 397 000  332 000  126 000  206 00044.917.027.9113.16.3949.721976  7 598 000  344 000  129 000  215 00045.216.928.3112.66.4549.881977  7 797 000  355 000  132 000  223 00045.416.928.6111.96.5250.001978  8 013 000  365 000  134 000  232 00045.616.728.9110.96.5650.281979  8 243 000  378 000  136 000  242 00045.816.529.3109.46.6150.581980  8 520 000  390 000  137 000  253 00045.916.229.8107.36.6651.041981  8 829 000  407 000  139 000  267 00046.115.830.3104.66.6451.521982  9 047 000  421 000  141 000  281 00046.215.430.8101.66.6252.091983  9 241 000  422 000  138 000  284 00045.614.930.798.36.6152.761984  9 509 000  431 000  138 000  293 00045.314.530.895.16.5953.221985  9 804 000  444 000  138 000  306 00045.214.031.292.06.5853.901986  10 113 000  459 000  140 000  318 00045.313.931.589.66.5954.041987  10 434 000  471 000  140 000  332 00045.213.431.887.26.5654.721988  10 760 000  482 000  142 000  340 00044.713.231.585.96.5054.931989  11 089 000  492 000  145 000  347 00044.413.131.385.36.4454.951990  11 431 000  505 000  150 000  355 00044.113.131.085.56.3954.871991  11 778 000  517 000  155 000  362 00043.913.230.786.36.3554.661992  12 129 000  528 000  160 000  368 00043.513.230.387.46.2954.481993  12 487 000  538 000  167 000  372 00043.113.429.788.76.1954.061994  12 849 000  549 000  174 000  374 00042.713.629.189.96.0853.531995  13 212 000  556 000  180 000  376 00042.113.628.590.75.9653.221996  13 575 000  564 000  187 000  377 00041.513.827.791.45.8352.821997  13 941 000  573 000  191 000  382 00041.113.727.491.65.7252.741998  14 315 000  588 000  197 000  391 00041.113.727.391.55.6752.581999  14 699 000  607 000  200 000  407 00041.313.627.790.65.6352.702000  15 092 000  620 000  203 000  417 00041.013.427.689.45.5352.932001  15 493 000  632 000  205 000  427 00040.813.227.587.95.4453.142002  15 914 000  652 000  208 000  445 00041.013.027.986.15.4653.422003  16 354 000  674 000  209 000  465 00041.212.828.484.35.4653.882004  16 809 000  694 000  211 000  483 00041.312.628.782.55.4554.182005  17 275 000  711 000  215 000  496 00041.112.428.780.85.4154.362006  17 751 000  728 000  215 000  513 00041.012.128.979.15.3554.862007  18 252 000  745 000  217 000  528 00040.811.928.977.45.3355.172008  18 777 000  762 000  218 000  544 00040.611.629.075.55.2855.662009  19 319 000  779 000  218 000  561 00040.311.329.073.75.2356.102010  19 878 000  795 000  219 000  576 00040.011.029.071.45.1656.582011  20 449 000  805 000  218 000  588 00039.410.628.769.15.0657.132012  21 033 000  815 000  215 000  600 00038.810.228.566.64.9957.792013  21 633 000  827 000  213 000  615 00038.29.828.464.04.9158.482014  22 300 000  842 000  212 000  629 00037.89.528.361.64.8658.942015  23 013 000  869 000  211 000  658 00037.89.228.659.14.8359.662016  23 712 000  895 000  211 000  684 00037.78.928.956.94.8260.232017  24 393 000  913 000  210 000  703 00037.48.628.854.84.7760.812018  25 077 000  921 000  210 000  711 00036.78.428.353.04.6961.182019  25 782 000  932 000  210 000  722 00036.18.228.051.44.6261.582020  26 491 000  941 000  223 000  718 00035.58.427.149.94.5460.832021  27 199 000  951 000  233 000  717 00034.98.626.448.54.4660.33 * CBR = crude birth rate (per 1,000); CDR = crude death rate (per 1,000); NC = natural change (per 1,000); IMR = infant mortality rate per 1,000 births; TFR = total fertility rate (number of children per woman)" ], [ "Ethnic groups", "Speakers of Makaa–Njem languages in Cameroon and neighbouring countries.The ethnic groups of Cameroon who speak Duala languages.", "*Cameroon Highlanders 31%*Equatorial Bantu 19%*Kirdi 11%*Fulani 10%*Baggara Arabs (also called Arab Shuwa)*Hausa*Mafa*Kanuri*Northwestern Bantu 8%*Eastern Nigritic 7%*Other African 13%*Non-African less than 1%" ], [ "Languages", "Linguistic survey of Nigeria, Cameroon, and BeninThere are 24 major African language groups in Cameroon; additionally, English and French are official languages.", "Cameroonian Pidgin English is also widely spoken.Peoples concentrated in the Southwest and Northwest Provinces—around Buea and Bamenda—use standard English and Cameroonian Pidgin English, as well as their local languages.", "In the three northern provinces—Adamawa, North, and Far North—either French or Fulfulde (the language of the Fulani) is widely spoken.", "Elsewhere, French is the principal second language, although pidgin and some local languages such as Ewondo, the dialect of a Beti clan from the Yaoundé area, have a wide currency.", "In Far North Region the northernmost constituent province of Cameroon, Mafa Language Arab Shuwa (an Arab dialect) and is spoken by the Baggara Arabs (also called Arab Shuwa).Indigenous languages of Cameroon include:*Arab Shuwa*Bamum*Basaa*Bikya*Bung*Kanuri*Ngumba*Yeni*Lamnso*Meta'*Mafa" ], [ "Other demographic statistics", "Estimated number of inhabitants (in thousands), based on 2005 data from the Food and Agriculture Organization.Demographic statistics according to the World Population Review in 2022.", "*One birth every 34 seconds\t*One death every 2 minutes\t*One net migrant every 111 minutes\t*Net gain of one person every 46 secondsThe following demographic statistics are from the CIA World Factbook.===Population===:29,321,637 (2022 est.", "):25,640,965 (July 2018 est.", "):24,994,885 (2017 est.", "):''Note'': estimates for this country explicitly take into account the effects of excess mortality due to AIDS; this can result in lower life expectancy, higher infant mortality and death rates, lower population and growth rates, and changes in the distribution of population by age and sex than would otherwise be expected (July 2018 est.", ")===Religion===Roman Catholic 38.3%, Protestant 25.5%, other Christian 6.9%, Muslim 24.4%, animist 2.2%, other 0.5%, none 2.2% (2018 est.", ")===Age structure===Population pyramid of Cameroon in 2020:''0-14 years:'' 42.34% (male 5,927,640/female 5,820,226):''15-24 years:'' 20.04% (male 2,782,376/female 2,776,873):''25-54 years:'' 30.64% (male 4,191,151/female 4,309,483):''55-64 years:'' 3.87% (male 520,771/female 552,801):''65 years and over:'' 3.11% (male 403,420/female 460,248) (2020 est.", "):''0-14 years:'' 42.15% (male 5,445,142 /female 5,362,166):''15-24 years:'' 19.6% (male 2,524,031 /female 2,502,072):''25-54 years:'' 31.03% (male 4,001,963 /female 3,954,258):''55-64 years:'' 3.99% (male 499,101 /female 524,288):''65 years and over:'' 3.23% (male 384,845 /female 443,099) (2018 est.", ")===Birth rate===:35.53 births/1,000 population (2022 est.)", "Country comparison to the world: 14th:35 births/1,000 population (2018 est.)", "Country comparison to the world: 21st:35.4 births/1,000 population (2017 est.", ")===Death rate===:7.73 deaths/1,000 population (2022 est.)", "Country comparison to the world: 101st:9.4 deaths/1,000 population (2018 est.)", "Country comparison to the world: 49th:9.6 deaths/1,000 population (2017 est.", ")===Total fertility rate===:4.55 children born/woman (2022 est.)", "Country comparison to the world: 19th:4.58 children born/woman (2018 est.)", "Country comparison to the world: 24th:According to Cameroon government website, average children per woman was 5.0 in 2004, 4.7 in 2016.===Net migration rate===:-0.31 migrant(s)/1,000 population (2022 est.)", "Country comparison to the world: 119th:-0.1 migrant(s)/1,000 population (2017 est.)", "Country comparison to the world: 104th:-0.1 migrants/1,000 population (2017 est.", ")===Mother's mean age at first birth===:20.1 years (2018 est.", "):note: median age at first birth among women 25-49:19.7 years (2011 est.", "):note: median age at first birth among women 25-29===Median age===:total: 18.5 years.", "Country comparison to the world: 209th:male: 18.2 years:female: 18.8 years (2020 est.", "):total: 18.6 years.", "Country comparison to the world: 208th:male: 18.5 years :female: 18.7 years (2018 est.", "):total: 18.5 years:male: 18.4 years:female: 18.7 years (2017 est.", ")===Population growth rate===:2.75% (2022 est.)", "Country comparison to the world: 15th:2.54% (2018 est.)", "Country comparison to the world: 20th:2.56% (2013 est.", ")===Urbanization===:urban population: 58.7% of total population (2022):rate of urbanization: 3.43% annual rate of change (2020-25 est.", "):urban population: 56.4% of total population (2018):rate of urbanization: 3.63% annual rate of change (2015-20 est.", "):Urban population: 58% of total population (2010):Rate of urbanization: 3.3% annual rate of change (2010–15 est.", ")===Sex ratio===:At birth: 1.03 male(s)/female:Under 15 years: 1.02 male(s)/female:15-64 years: 1.01 male(s)/female:65 years and over: 0.85 male(s)/female:Total population: 1.01 male(s)/female (2009 est.", ")===Life expectancy at birth===:total population: 63.27 years Country comparison to the world: 210th:male: 61.49 years:female: 65.09 years (2022 est.", "):total population: 59 years:male: 57.6 years:female: 60.4 years (2017 est.", ")===Contraceptive prevalence rate===:19.3% (2018):34.4% (2014)===Dependency ratios===:total dependency ratio: 85.9 (2015 est.", "):youth dependency ratio: 80 (2015 est.", "):elderly dependency ratio: 5.9 (2015 est.", "):potential support ratio: 17 (2015 est.", ")===School life expectancy (primary to tertiary education)===:total: 12 years:male: 13 years:female: 11 years (2016)===HIV/AIDS===:Adult prevalence rate: 3.7% (2017 est.", "):People living with HIV/AIDS: 510,000 (2017 est.", "):Deaths: 24,000 (2017 est.", ")===Major infectious diseases===:Degree of risk: very high:Food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and hepatitis E, and typhoid fever:Vectorborne diseases: malaria and yellow fever:Water contact disease: schistosomiasis:Respiratory disease: meningococcal meningitis:Animal contact disease: rabies (2009)===Nationality===:Noun: Cameroonian(s):Adjective: Cameroonian===Literacy===:Definition: age 15 and over can read and write:Total population: 77.1% ''(2018 est.", ")''::Male: 82.6%::Female: 71.6%===Education expenditure===: 2.8% of GDP (2013)" ], [ "References", "'''Attribution:'''*" ], [ "External links", "* Institut National de la Statistique du Cameroun* Cameroon Undertakes Nationwide Census, a November 2005 article from Voice of America*UNDP.", "2006.", "''Beyond scarcity: Power, poverty and the global water crisis.", "Human Development Report 2006.''", "New York: United Nations Development Programme (UNDP)." ] ]

[ [ "Politics of Cameroon" ], [ "Introduction", "The '''politics of Cameroon''' takes place in a framework of a unitary presidential republic, whereby the President of Cameroon is both head of state and head of government, and of a multi-party system.", "A prime ministerial position exists and is nominally head of government, implying a semi-presidential system, although de facto only serves to assist the president.", "Executive power is exercised by the government.", "Legislative power is vested in both the government and the National Assembly of Cameroon." ], [ "Political background", "The government adopted legislation in 1997 to authorize the formation of multiple political parties and ease restrictions on forming civil associations and private newspapers.", "Cameroon's first multiparty legislative and presidential elections were held in 1992 followed by municipal elections in 1996 and another round of legislative and presidential elections in 1997.Because the government refused to consider opposition demands for an independent election commission, the three major opposition parties boycotted the October 1997 presidential election, which Biya easily won.", "The leader of one of the opposition parties, Bello Bouba Maigari of the NUDP, subsequently joined the government.Cameroon has a number of independent newspapers.", "Censorship was abolished in 1996, but the government sometimes seizes or suspends newspapers and occasionally arrests journalists.", "Although a 1990 law authorizes private radio and television stations, the government has not granted any licenses as of March 1998.The Cameroonian Government's human rights record has been improving over the years but remains flawed.", "There continue to be reported abuses, including beatings of detainees, arbitrary arrests, and illegal searches.", "The judiciary is frequently corrupt, inefficient, and subject to political influence.Worthy of note is the fact that Cameroon is the only country in which two Constitutions are applicable side by side.", "For example, the 1972 Constitution designates the Prime Minister as constitutional successor of the Head of State in case of incapacity, death, resignation or unaccountable absence of the incumbent.", "Contrarily, the 1996 Constitutional Reform designates the President of the Senate as constitutional successor; but the Senate (provided for by 1996 Reform) does not exist.", "Apart from increasing the presidential mandate from 5 years to 7 years, very few amendments of the 1996 Constitutional Reform have been applied." ], [ "Executive branch", "|PresidentPaul BiyaCameroon People's Democratic Movement6 November 1982Prime MinisterJoseph Dion NguteCameroon People's Democratic Movement4 January 2019Cameroon President Paul Biya (right) with Colin Powell|alt=Colin Powell and Cameroon president Paul Biya, smiling and talkingThe 1972 constitution of the '''Republic of Cameroon''' as modified by 1996 reforms provides for a strong central government dominated by the executive.", "The president is empowered to name and dismiss cabinet members (regardless of parliamentary representation), judges, generals, provincial governors, prefects, sub-prefects, and heads of Cameroon's parastatal (about 100 state-controlled) firms, obligate or disburse expenditures, approve or veto regulations, declare states of emergency, and appropriate and spend profits of parastatal firms.", "The president is not required to consult the National Assembly.", "In 2008, a constitutional amendment was passed that eliminated term limits for president.The judiciary is subordinate to the executive branch's Ministry of Justice.", "The Supreme court may review the constitutionality of a law only at the president's request.All local government officials are employees of the central government's Ministry of Territorial Administration, from which local governments also get most of their budgets.While the president, the minister of justice, and the president's judicial advisers (the Supreme Court) top the judicial hierarchy, traditional rulers, courts, and councils also exercise functions of government.", "Traditional courts still play a major role in domestic, property, and probate law.", "Tribal laws and customs are honored in the formal court system when not in conflict with national law.", "Traditional rulers receive stipends from the national government." ], [ "Legislative branch", "The 180-member National Assembly meets in ordinary session three times a year (March/April, June/July, and November/December), and has seldom, until recently, made major changes in legislation proposed by the executive.", "Laws are adopted by majority vote of members present or, if the president demands a second reading, of a total membership.Following government pledges to reform the strongly centralized 1972 constitution, the National Assembly adopted a number of amendments in December 1995 which were promulgated in January 1996.The amendments call for the establishment of a 100-member senate as part of a bicameral legislature, the creation of regional councils, and the fixing of the presidential term to 7 years, renewable once.", "One-third of senators are to be appointed by the President, and the remaining two-thirds are to be chosen by indirect elections.", "The government has established the Senate in 2013." ], [ "Political parties and elections" ], [ "Judicial branch", "The judiciary is subordinate to the executive branch's Ministry of Justice.", "The Supreme Court may review the constitutionality of a law only at the president's request." ], [ "The role of women", "In an article on the construction of a ‘model Cameroonian woman’ in the Cameroonian parliament, Lilian Atanga, examines arguments used to perpetuate a popular ideal and discourses which \"sustain and maintain the status quo (e.g.", "of women as domestic or women as cooks)\"." ], [ "International organization participation", "Cameroon is member of:ACCT, ACP, AfDB, BDEAC, C, CEEAC, ECA, FAO, FZ, G-77, IAEA, IBRD, ICAO, ICC, ICRM, IDA, IDB, IFAD, IFC, IFRCS, ILO, IMF, IMO, Inmarsat, Intelsat, Interpol, IOC, ITU, ITUC, NAM, OAU, OIC, OPCW, PCA, UDEAC, UN, UNCTAD, UNESCO, UNIDO, UNITAR, UPU, WCO, WFTU, WHO, WIPO, WMO, WToO, WTrO" ], [ "See also", "*Cameroon public administration structure*List of governments of Cameroon" ], [ "References" ] ]

[ [ "Economy of Cameroon" ], [ "Introduction", "Cocoa FarmThe '''economy of Cameroon''' was one of the most prosperous in Africa for a quarter of a century after independence.", "The drop in commodity prices for its principal exports – petroleum, cocoa, coffee, and cotton – in the mid-1980s, combined with an overvalued currency and economic mismanagement, led to a decade-long recession.", "Real per capita GDP fell by more than 60% from 1986 to 1994.The current account and fiscal deficits widened, and foreign debt grew.", "Yet because of its oil reserves and favorable agricultural conditions, Cameroon still has one of the best-endowed primary commodity economies in sub-Saharan Africa." ], [ "Agriculture", "In 2018, Cameroon produced:* 5million tons of cassava (13th largest producer in the world);* 3.9million tonnes of plantain (3rd largest producer in the world, only behind Congo and Ghana);* 2.6million tons of palm oil (7th largest producer in the world);* 2.3million tons of maize;* 1.9million tons of taro (3rd largest producer in the world, second only to Nigeria and China);* 1.4million tons of sorghum;* 1.2million tons of banana;* 1.2million tons of sugarcane;* 1million tons of tomato (19th largest producer in the world);* 674,000 tonnes of yam (7th largest producer in the world);* 594,000 tons of peanut;* 410,000 tons of sweet potato;* 402,000 tons of beans;* 332,000 tons of rice;* 310,000 tons of pineapple;* 307,000 tons of cocoa (5th largest producer in the world, after Ivory Coast, Ghana, Indonesia and Nigeria);* 302,000 tons of potato;* 301,000 tons of onion;* 249,000 tons of cotton.In addition to smaller productions of other agricultural products, such as coffee (33,000 tons) and natural rubber (55,000 tons)." ], [ "Finance and banking", "Cameroon's financial system is the largest in the CEMAC region.", "Access to financial services is limited, particularly for SMEs.", "Aside from a traditional tendency for banks to prefer dealing with large, established companies, determining factors are also found in interest rates for loans to SMEs being capped at 15 percent and being heavily taxed.", "As of 2006, bank loans to SMEs hardly reached 15 percent of total outstanding loans (Molua, 2002).Less than 5 percent of Cameroonians have access to a bank account.", "While the microfinance sector is consequently becoming increasingly important, its development is hampered by a loose regulatory and supervisory framework for microfinance institutions (MFIs).", "The banking sector is highly concentrated and dominated by foreign commercial banks.", "6 out of the 11 largest commercial banks are foreign-owned, and the three largest banks hold more than 50 percent of total financial system assets.", "While foreign banks generally display good solvency ratios, small domestic banks are in a much weaker position.", "Their capitalization is well below the average of banks in the CEMAC region and their profits are close to 2 percent, compared to 20 percent for foreign banks in the country.", "This is partially explained by the high levels of non-performing loans, which reached 12 percent in 2007, leading to most banks holding large amounts of excess reserves as a percentage of deposits and large levels of unutilized liquidity.In 2018, Cameroon's financial system is being requested by the International Monetary Fund (IMF) to increase its tax base to cover the losses from the North-West and South-West Cameroon's regions instabilities, the loss of oil revenue, the failure to deliver on port facilities, and the decline in oil production from mature oil fields." ], [ "Macro-economic trend", "Cameroon became an oil-producing country in 1977.Claiming to want to make reserves for difficult times, the authorities manage \"off-budget\" oil revenues in total opacity (the funds are placed in Paris, Switzerland and New York accounts).", "Several billion dollars are thus diverted to the benefit of oil companies and regime officials.", "The influence of France and its 9,000 nationals in Cameroon remains considerable.", "African Affairs magazine noted in the early 1980s that they \"continue to dominate almost all key sectors of the economy, much as they did before independence.", "French nationals control 55% of the modern sector of the Cameroonian economy and their control over the banking system is total.Recent signs, however, are encouraging.", "As of March 1998, Cameroon's fifth IMF program – a 3-year enhanced structural adjustment program approved in August 1997 – is on track.", "Cameroon has rescheduled its Paris Club debt at favorable terms.", "GDP has grown by about 5% a year beginning in 1995.There is cautious optimism that Cameroon is emerging from its long period of economic hardship.Cameroonian exports in 2006The Enhanced Structural Adjustment Facility (ESAF) signed recently by the IMF and Government of Cameroon calls for greater macroeconomic planning and financial accountability; privatization of most of Cameroon's nearly 100 remaining non-financial parastatal enterprises; elimination of state marketing board monopolies on the export of cocoa, certain coffees, and cotton; privatization and price competition in the banking sector; implementation of the 1992 labor code; a vastly improved judicial system; and political liberalization to boost investment.France is Cameroon's main trading partner and source of private investment and foreign aid.", "Cameroon has an investment guaranty agreement and a bilateral accord with the United States.", "USA investment in Cameroon is about $1 million, most of it in the oil sector.", "Inflation has been brought back under control.", "Cameroon aims at becoming emerging by 2035.The government embarked upon a series of economic reform programs supported by the World Bank and International Monetary Fund (IMF) beginning in the late 1980s.", "Many of these measures have been painful; the government slashed civil service salaries by 65% in 1993.The CFA franc – the common currency of Cameroon and 13 other African states – was devalued by 50% in January 1994.The government failed to meet the conditions of the first four IMF programs.This is a chart of trend of gross domestic product of Cameroon at market prices estimated by the International Monetary Fund with figures in millions of Central African CFA Francs.", "Year Gross Domestic Product US Dollar Exchange 1980 1,600,186 209.20 Francs 1985 4,355,977 471.12 Francs 1990 3,804,428 300.65 Francs 1995 4,686,286 518.62 Francs 2000 6,612,385 658.21 Francs 2005 8,959,279 527.29 FrancsThe following table shows the main economic indicators in 1980–2022.Inflation below 5% is in green.YearGDP(in Bil.", "US$PPP)GDP per capita(in US$ PPP)GDP(in Bil.", "US$nominal)GDP growth(real)Inflation rate(in Percent)Government debt(in % of GDP)198011.11,2638.859.9%7.7%n/a198114.31,57210.0317.1%7.5%n/a198216.31,7479.627.6%15.3%n/a198318.11,8879.696.8%20.5%n/a198420.12,04710.247.5%12.1%n/a198522.42,22310.708.1%4.2%n/a198624.42,35713.956.8%4.3%n/a198724.52,29816.15 -2.2%2.8%n/a198823.42,12916.40 -7.9%1.7%n/a198923.92,11014.63 -1.8%1.6%n/a199023.21,99214.64 -6.2%1.5%n/a199123.11,92216.33 -3.8% -0.6%n/a199222.91,85014.96 -3.1%1.9%n/a199322.71,78015.61 -3.2% -3.7%n/a199422.61,72210.62 -2.5%12.7%n/a199523.91,76610.083.3%25.8%n/a199625.51,83611.234.9%3.9%n/a199727.31,91311.355.3%4.8%n/a199829.01,97411.344.9%3.2%68%199930.62,02611.554.1%1.8%68%200032.32,08410.253.4%1.2%76%200134.22,14510.953.4%4.5%62%200236.42,22412.374.8%2.8%57%200338.92,31815.945.0%0.6%52%200442.62,46918.806.6%0.3%52%200544.52,50919.531.2%2.0%44%200647.52,60520.913.5%4.9%18%200750.82,71023.934.1%1.1%14%200853.22,76427.712.9%5.3%11%200955.02,77727.902.6%3.0%11%201057.22,81427.532.9%1.3%14%201160.52,89230.633.5%3.0%15%201263.62,95930.174.5%2.4%15%201369.13,13033.735.0%2.1%17%201475.13,31336.405.8%1.9%21%201579.13,39632.215.6%2.7%32%201684.43,52733.814.5%0.9%32%201790.03,66536.093.5%0.6%37%201895.93,80339.994.0%1.1%38%2019101.03,90139.673.4%2.5%42%2020102.73,87040.860.5%2.5%45%2021110.94,07345.393.6%2.3%46%2022123.34,41944.323.8%4.6%47%}" ], [ "Gallery", "File:Douala.JPG|DoualaFile:Limbe1.png|A touristic area in LimbeFile:YaoundeSportPalace.png|Yaoundé Sport palaceFile:Fulani herd in the dust.jpg|A Fulani herder drives his cattle in northern Cameroon.File:Asky plane 7810.jpg|Douala International AirportFile:Touristic Buses.jpg|Intercity buses in transit during the night (Touristique Express)File:WL-Cameroun-Train Yaoundé-Ngaoundéré.jpg|Interurban passenger train on the move in Cameroon (Douala-Yaounde-Ngaoundere)File:Nouveau pont sur le Wouri 04.jpg|Douala SeaportFile:Transport de boissons 01.jpg|A truck transporting beers to various localities in Cameroon" ], [ "See also", "* Cameroon* Transport in Cameroon* United Nations Economic Commission for Africa" ], [ "References" ], [ "External links", "** Cameroon latest trade data on ITC Trade Map* World Bank Summary Trade Statistics Cameroon" ] ]

[ [ "Telecommunications in Cameroon" ], [ "Introduction", "'''Telecommunications in Cameroon''' include radio, television, fixed and mobile telephones, and the Internet." ], [ "History", "During German rule, It was set up in the protectorate of Kamerun the first telegraph line, the first telephone line, and the first wireless telegraph.", "However, the country remained undeveloped in telecommunications.", "During First World War, Germans followed a scorched-earth policy that meant the destruction of communication lines, included telephone and telegraph.In British Cameroon, from 1916 to 1950s, communications in the country relied on flag post runners that had been described as \"human telephone lines\".", "Paths followed by the runners served as a base of the development of telegraph lines in the territory.", "For instance, the line from Buea-Kumba to Ossidinge used the same paths that the mail runners.", "In the mid-1930s, the wiring of British Cameroon received more support." ], [ "Radio and television", "* Radio stations:** state-owned Cameroon Radio Television (CRTV); one private radio broadcaster; about 70 privately owned, unlicensed radio stations operating, but subject to closure at any time; foreign news services are required to partner with a state-owned national station (2007);** 2 AM, 9 FM, and 3 shortwave stations (2001).", "* Television stations:** state-owned Cameroon Radio Television (CRTV), 2 private TV broadcasters (2007);** one station (2001).BBC World Service radio is available via local relays (98.4 FM in Yaounde, the capital).The government maintains tight control over broadcast media.", "State-owned Cameroon Radio Television (CRTV), operates both a TV and a radio network.", "It was the only officially recognized and fully licensed broadcaster until August 2007 when the government issued licenses to two private TV and one private radio broadcasters.Approximately 375 privately owned radio stations were operating in 2012, three-fourths of them in Yaounde and Douala.", "The government requires nonprofit rural radio stations to submit applications to broadcast, but they were exempt from licensing fees.", "Commercial radio and television broadcasters must submit a licensing application and pay an application fee and thereafter pay a high annual licensing fee.", "Several rural community radio stations function with foreign funding.", "The government prohibits these stations from discussing politics.In spite of the government's tight control, Reporters Without Borders reported in its 2011 field survey that \"it is clear from the diversity of the media and the outspoken reporting style that press freedom is a reality\"." ], [ "Telephones", "* Calling code: +237* International call prefix: 00* Main lines:** 737,400 lines in use, 88th in the world (2012);** 130,700 lines in use (2006).", "* Mobile cellular:** 13.1 million lines, 64th in the world (2012);**   4.5 million lines (2007).", "* Telephone system: system includes cable, microwave radio relay, and tropospheric scatter; Camtel, the monopoly provider of fixed-line service, provides connections for only about 3 per 100 persons; equipment is old and outdated, and connections with many parts of the country are unreliable; mobile-cellular usage, in part a reflection of the poor condition and general inadequacy of the fixed-line network, has increased sharply, reaching a subscribership base of 50 per 100 persons (2011).", "* Communications cables: South Atlantic 3/West Africa Submarine Cable (SAT-3/WASC) fiber-optic cable system provides connectivity to Europe and Asia (2011); Africa Coast to Europe (ACE), cable system connecting countries along the west coast of Africa to each other and to Portugal and France, is planned.", "* Satellite earth stations: 2 Intelsat (Atlantic Ocean) (2011)." ], [ "Internet", "* Top-level domain: .cm* Internet users:** 1.1 million users, 113th in the world; 5.7% of the population, 184th in the world (2012).", "** 985,565 users (2011);** 749,600 users, 106th in the world (2009).", "* Fixed broadband: 1,006 subscriptions, 180th in the world; less than 0.05% of the population, 190th in the world (2012).", "* Wireless broadband: Unknown (2012).", "* Internet hosts:** 10,207 hosts, 134th in the world (2012);**        69 hosts (2008).", "* IPv4: 137,728 addresses allocated, less than 0.05% of the world total, 6.8 addresses per 1000 people (2012).", "* Internet service providers (ISPs): ** Creolink CommunicationsA number of projects are underway that will improve Internet access, telecommunications, and Information and communications technology (ICT) in general:* Implementation of the e-post project, connecting 234 post offices throughout the country;* Extension of the national optical fiber network, installation of the initial 3,200 km of fiber is complete and studies for the installation of an additional 3,400 km are underway;* Construction of multipurpose community telecentres, some 115 telecentres are operating with an additional 205 under construction;* Construction of metropolitan optical loops, the urban optical loop of Douala is complete and construction of the Yaounde loop is underway;* Construction of submarine cable landing points;* Establishment of public key infrastructure (PKI);* Construction of a regional technology park to support the development of ICTs.===Internet censorship and surveillance===There are no government restrictions on access to the Internet or reports that the government monitors e-mail or Internet chat rooms.Although the law provides for freedom of speech and press, it also criminalizes media offenses, and the government restricts freedoms of speech and press.", "Government officials threaten, harass, arrest, and deny equal treatment to individuals or organizations that criticize government policies or express views at odds with government policy.", "Individuals who criticize the government publicly or privately sometimes face reprisals.", "Press freedom is constrained by strict libel laws that suppress criticism.", "These laws authorize the government, at its discretion and the request of the plaintiff, to criminalize a civil libel suit or to initiate a criminal libel suit in cases of alleged libel against the president and other high government officials.", "Such crimes are punishable by prison terms and heavy fines.Although the constitution and law prohibit arbitrary interference with privacy, family, home, or correspondence, these rights are subject to restriction for the \"higher interests of the state\", and there are credible reports that police and gendarmes harass citizens, conduct searches without warrants, and open or seize mail with impunity." ], [ "See also", "* Cameroon Radio Television, government-controlled national broadcaster.", "* Commonwealth Telecommunications Organisation* List of terrestrial fibre optic cable projects in Africa* Media of Cameroon* Cameroon" ], [ "References", "* *" ], [ "External links", "* Antic.cm, top-level domain registry for Cameroon (.cm).", "* Ministry of Posts and Telecommunications, Cameroon (MINPOSTEL) .", "English translation." ] ]

[ [ "Transport in Cameroon" ], [ "Introduction", "This article provides a breakdown of the transportation options available in Cameroon.", "The options available to citizens and tourists include railways, roadways, waterways, pipelines, and airlines.", "These avenues of transportation are used by citizens for personal transportation, by businesses for transporting goods, and by tourists for both accessing the country and traveling while there.Bush taxi in the East Province" ], [ "Railways", "thumbRailways in Cameroon are operated by Camrail, a subsidiary of French investment group Bolloré.", "As of May 2014 Camrail operated regular daily services on three routes:* Douala - Kumba* Douala - Yaoundé* Yaoundé - Ngaoundéré* Kribi - Mbalam and Nabeba in Republic of the Congo - under construction in 2022.", "* Edéa - Kribi - proposed connection to deep water port.There are no rail links with neighboring countries except Republic of the Congo." ], [ "Roadways", "Bus Finexs VoyageBuses in Yaoundé''Total highways:'' 50,000 km''Paved:'' 5,000 km''Unpaved:'' 45,000 km (2004)Cameroon lies at a key point in the Trans-African Highway network, with three routes crossing its territory:* Dakar-N'Djamena Highway, connecting just over the Cameroon border with the N'Djamena-Djibouti Highway* Lagos-Mombasa Highway* Tripoli-Cape Town HighwayCameroon's central location in the network means that efforts to close the gaps which exist in the network across Central Africa rely on the Cameroon's participation in maintaining the network, and the network has the potential to have a profound influence on Cameroon's regional trade.", "Except for the several relatively good toll roads which connect major cities (all of them one-lane) roads are poorly maintained and subject to inclement weather, since only 10% of the roadways are tarred.", "It is likely for instance that within a decade, a great deal of trade between West Africa and Southern Africa will be moving on the network through Yaoundé.National highways in Cameroon:Rues et pistes de Douala 04*N1: Yaoundé - Bertoua - Ngaoundéré - Garoua - Maroua - Kouséri, border with Chad.", "*N2: Yaoundé - Mbalmayo - Ebolowa - Woleu Ntem, border with Gabon.", "*N3: Yaoundé - Edéa - Douala - Idenau.", "*N4: Yaoundé - Bafia - Bafoussam.", "*N5: Douala - Nkongsamba - Bafang - Bafoussam.", "*N6: Ejagham, border with Nigeria - Bamenda - Bafoussam - Tibati - Lokoti.", "*N7: Edéa - Kribi.", "*N8: Mutengene - Kumba - Mamfé.", "*N9: Mbalmayo - Nki, border with Congo.", "*N10: Yaoundé - Bertoua - Batouri - Kenzou, border with the Central African Republic.", "*N11 Bamenda Ring Road Linking, Mezam, Ngokitujia, Mbui, Boyo and MenchumPrices of petrol rose steadily in 2007 and 2008, leading to a transport union strike in Douala on 25 February 2008.The strike quickly escalated into violent protests and spread to other major cities.", "The uprising finally subsided on 29 February." ], [ "Waterways", "Car carrier GRANDE CAMEROON à Casablanca2,090 km; of decreasing importance.", "Navigation mainly on the Benue River; limited during rainy season." ], [ "Seaports and harbors", "* Douala - main port, railhead, and second largest city.", "* Bonaberi - railhead to northwest* Garoua* Kribi - oil pipeline from Chad** Kribi South - proposed iron ore export port, about 40 km south of Kribi.", "* Tiko" ], [ "Pipelines", "888 km of oil line (2008)" ], [ "Airports", "Aéroport de DoualaAircraft at the Douala International Airport, CameroonFront view of Douala International AirportThe main international airport is the Douala International Airport and a secondary international airport at Yaoundé Nsimalen International Airport.", "As of May 2014 Cameroon had regular international air connections with nearly every major international airport in West and Southwest Africa as well as several connections to Europe and East Africa.In 2008 there were 34 airports, only 10 of which had paved runways.", "* List of airports in Cameroon=== Airports - with paved runways ===''total:''10''over 3,047 m:''2''2,438 to 3,047 m:''4''1,524 to 2,437 m:''3''914 to 1,523 m:''1 (2008)=== Airports - with unpaved runways ===''total:''24''1,524 to 2,437 m:''4''914 to 1,523 m:''14''under 914 m:''6 (2008)" ], [ "See also", "* Camrail* Cameroon* Transport News* African Integrated High Speed Railway Network (AIHSRN)* Railway stations in Cameroon" ], [ "References", "* Sundance Resources Ltd report" ] ]

[ [ "Cameroon Armed Forces" ], [ "Introduction", "The '''Cameroon Armed Forces''' () are the military of the Republic of Cameroon.", "The armed forces number 40,000 personnel in ground, air, and naval forces.", "There are approximately 40,000 troops in the army across three military regions.", "Approximately 1,300 troops are part of the Cameroonian Navy, which is headquartered at Douala.", "Under 600 troops are part of the Air Force.", "There is an additional 12,500 paramilitary troops that serve as a gendarmerie (policing force) or reconnaissance role.The Cameroonian armed forces have bases spread all over Cameroon, including in Ngaoundéré.", "Air Force bases are located in Garoua, Yaoundé, Douala and Bamenda.It has generally remained loyal to the government and acted to ensure the stability of the regime, and not acted as an independent political force.", "Traditional dependence on the French defense capability, although reduced, continues to be the case as French military advisers remain closely involved in preparing the Cameroonian forces for deployment to the contested Bakassi Peninsula." ], [ "Army", "With over 40,000 troops the Army remains the most important component in terms of numbers.", "The Army is under the responsibility of the Chief of Staff, Major-General Nkoa Atenga, whose staff is in Yaoundé.Currently the organization dates from 2001 with a distribution in several types of units: combat units, response units (''unités d'intervention''), ''unités de soutien et d'appui'', and finally special reserve units as part of 3 joint military régions (''interarmées'') and the 10 military land sectors.Army units have been trained and equipped to fight in the swampy coastal terrain facing the Bakassi peninsula.", "Although prepared for an armed conflict with Nigeria in recent years, the Cameroon Army does not have operational experience against other forces, therefore, it is not possible to assess its ability to respond to changing threats and opposing tactics.Combat units of the army include:* The Headquarters Brigade, located in Yaoundé.", "This brigade is responsible for protecting the capital and supporting the institutions.", "The President of the Republic has to allow any of its deployments.", "* Three command and support battalions;* The Rapid Intervention Battalion (''Btaillon d'Intervention Rapide'', BIR)* The (''Brigade d'Intervention Rapide'', or also BIR), (which currently has no general staff) and is made up of three rapid response battalions, stationed in Douala, Tiko and Koutaba.", "These three battalions are respectively the Special Amphibious Battalion (Bataillon Spécial Amphibie; BSA), the Bataillon des Troupes Aéroportées (BTAP), and the Armored Reconnaissance Battalion (Bataillon Blindé de Reconnaissance; BBR) equipped with Type 07P infantry fighting vehicle and PTL-02 tank destroyer bought recently from China.", "The BSA is inspired by the French Special Forces.", "This brigade is a tactical battle unit under the authority of the Chief of Staff of the armed forces.", "For this to be engaged, the President’s agreement is necessary.", "* Five motorised infantry brigades, supposed to be stationed in one military sector but which can then be engaged without any regard to the territorial division of the country.", "These brigades currently do not have a general staff.", "In theory, they consist of 11 motorised infantry battalions; 5 support battalions and 3 backing battalions; however, the motorised battalions are in reality not operational due to a lack of staff, equipment and vehicles.=== Organization ===The territory is divided into 5 combined arms military regions (RMIA):* RMIA1 (Yaoundé)* RMIA2 (Douala)* RMIA3 (Garoua)* RMIA4 (Maroua)* RMIA5 (Bamenda)=== 1st Military Region ===* 11th Ebolowa Brigade:** 11th BCS (command and support battalion) in Ebolowa** 12th BIM (motorized infantry battalion) in Ebolowa** 12th BIM at Djoum** 13th BIM at Ambam** 11th BA (support battalion) at Sangmélima* 12th Bertoua brigade** 12th BCS in Bertoua** 14th BIM in Bertoua**15th BIM to Yokadouma **16th BIM at Garoua-Boulaï**12th BA in Bertoua=== 2nd Military Region ===* Rapid Intervention Brigade** Headquarters at Bafoussam**Special Amphibious Battalion (BSA) at Tiko**Airborne Battalion (BTAP) in Koutaba**Armored Reconnaissance Battalion (BBR) in Douala* 21st Motorized infantry brigade of Buéa** 21st BCS in Buéa** 21 BIM in Buéa** 22nd BIM at Mamfé** 23rd BIM at Loum** 24th BIM at Akwaya** 21st BA in Kumba* 201st Douala Air Base** 21st Air Transport Squadron**211st Transport and Assault Transport Squadron**212nd Transport and Assault Transport Squadron**22nd Air Squadron**221st Transport and Assault Transport Squadron**222nd Reconnaissance Squadron===Army equipment===Oerlikon GDF of the Cameroon Armed Forces in 2016." ], [ "Cameroonian Air Force", "The air force has bases in Garoua, Koutaba, Yaoundé, Douala and Bamenda.", "The Cameroonian Air Force was founded in 1960, the year of independence from France.", "There are under 400 troops in the air force.", "Cameroon's Air Force has 9 combat-capable aircraft." ], [ "Cameroon Navy", "Cameroonian sailors reviewed by an American admiral in Douala, 2015.There are about 1,300 troops in the navy including naval infantry.===History===Around May 1999, Philip Njaru wrote a newspaper article where he alleged ill-treatment of civilians conducted by the 21st Navy Battalion based in Ekondo-Titi.", "In late May Njaru was approached by the local captain who asked Njaru \"to stop writing such articles and to disclose his sources\".", "Refusing to do this, Njaru five days later found his house encircled by armed soldiers, and escaped to Kumba.", "Here, he was assaulted by police in June 2001, with no particular reason stated.", "Njaru complained to the local authorities, but later learned that \"his complaint had not been received\".Cameroon's Marine Nationale République modernised and increased its capabilities during 2000 with the acquisition of a number of small Rodman patrol craft and the retirement of some small older craft.", "A number of small patrol boats have been acquired or ordered from France.", "Latest estimates indicate naval strength consists of two combat patrol vessels, three coastal patrol vessels and approximately 30 smaller inshore and river patrol craft allocated to both the navy and the local gendarmerie.", "These include two 135 tonne Yunnan-class landing craft, which are able to carry and launch smaller craft for troop insertions.", "Some effort has been made to assess equipment needs to bring L'Audacieux P103 and Bakassi P104 to an effective combat status.", "This has resulted in weapons capabilities being reduced in favour of an increase in serviceability and the service is now effectively without missile attack capabilities.", "Bakassi (a Type P 48S missile patrol craft) completed a major refit at Lorient, France in August 1999.This included removing the Exocet missile system and EW equipment, and fitting a funnel aft of the mainmast to replace the waterline exhausts.", "New radars were also installed.", "Bakassi is now armed only with 40 mm cannon.", "Although the Bizerte (P48 large patrol craft) class L'Audacieux is fitted for SS-12M missiles these are not embarked and its operational status is in some doubt, having not been reported at sea since 1995.The Quartier-Maître Alfred Moto patrol boat was listed as out of service in 1991 but has since been reactivated.===Ships===Cameroon Navy patrol boat during a military parade in Douala, 2019List of active ships.", "* 1: DIPIKAR patrol boat (former French navy \"Grèbe\", upgraded with LYNCEA PATROL CMS) (Gun)* 2: FRA P-48 (Gun)* 6: Rodman 101/46 (Gun)* 1: Quartier class (Gun)* 3: Boston Whaler patrol boats* 1: Bakassi class patrol boat (P48S type)* 1: L’Audacieux class missile FAC (P48 type)* 1: Alfred Motto class patrol craft* 20: Swiftships type river boats* 2: Yunnan landing craft utility* 8: Simoneau* 2: Aresa 2400 CPV Defender patrol boats* 1: Aresa 2300 landing craft* 6: Aresa 750 Commandos RIBs* 5: 1200 Stealth RIBs* 1: 1200 Defcon RIB* 2: P108 and P109 patrol boatsTwo 32-metre patrol boats are expected to be delivered in February 2014." ], [ "Gendarmerie", "The Gendarmerie is a paramilitary force composed of about 9,000 soldiers as of 2016.It performs both law enforcement and national security responsibilities across the country.", "(See Gendarmerie)" ], [ "Military education", "After an initial period of development, training requirements were formalized in an April 1967 per government decree.", "There was a shortage of Cameroonian instructors at that time.", "The two educational institutions of the nation are the following:* Combined Services Military Academy (Ecole Militaire Interarmes Camerounaises—EMIAC): It is the interforce academy for officers, being the educational center for future officers of the armed forces and the National Gendarmerie.", "It was established in 1959 and inaugurated on 18 January 1961.No officers were graduated until 1970.Every graduation of cadets takes place on 18 January.", "* Non-Commissioned Officer Training School (''Ecole des sous officiers du cameroun'')Both commissioned and noncommissioned officers were sent to various military schools in France, Greece, and the Soviet Union.", "The total number of Cameroonian military cadets with a Russian educational background were few." ], [ "References" ], [ "External links", "* Military appointments" ] ]

[ [ "Foreign relations of Cameroon" ], [ "Introduction", "Nations with which Cameroon has diplomatic relations.Cameroon's noncontentious, low-profile approach to foreign relations puts it squarely in the middle of other African and developing country states on major issues.", "It supports the principles of non-interference in the affairs of third world countries and increased assistance to underdeveloped countries.", "Cameroon is an active participant in the United Nations, where its voting record demonstrates its commitment to causes that include international peacekeeping, the rule of law, environmental protection, and Third World economic development.", "In the UN and other human rights fora, Cameroon's non-confrontational approach has generally led it to avoid criticizing other countries.Cameroon enjoys good relations with the United States and other developed countries.", "Cameroon enjoys generally good relations with its African neighbors.", "It supports UN peacekeeping activities in Central Africa." ], [ "International disputes", "Delimitation of international boundaries in the vicinity of Lake Chad, the lack of which led to border incidents in the past, is complete and awaits ratification by Cameroon, Chad, Niger, and Nigeria; dispute with Nigeria over land and maritime boundaries around the Bakasi Peninsula and Lake Chad is currently before the International Court of Justice (ICJ), as is a dispute with Equatorial Guinea over the exclusive maritime economic zone.", "As of 10 October 2012, it has been resolved that Cameroon own Bakassi.Cameroon also faces a complaint filed with the African Commission on Human Rights by the Southern Cameroons National Council (SCNC) and the Southern Cameroons Peoples Organisation (SCAPO) against the Government of the Republic of Cameroon, in which the complainants allege that the Republic of Cameroon is illegally occupying the territory of Southern Cameroons.", "The SCNC and SCAPO ultimately seek the independence of the territory of Southern Cameroons.", "As of 2008, both parties have submitted briefs and responded to the Human Rights Commissions' inquiries.", "A ruling by the African Commission on Human Rights is awaited." ], [ "Bilateral relations", " Country Formal Relations BeganNotes20 August 1973Both countries established diplomatic relations on 20 August 19731 January 1964Both countries established diplomatic relations on 1 January 196421 August 1979Both countries established diplomatic relationbs on 2 January 1975Both countries established diplomatic relations on 2 January 197528 May 2007Both countries established diplomatic relations on 28 May 20072 March 2002Both countries established diplomatic relations on 2 March 2002* Both countries are full members of The Commonwealth.", "* Cameroon is accredited to Australia through its embassy in Tokyo, Japan.", "* Australia is represented in Cameroon through its High Commission in Abuja, Nigeria.24 February 1995On 24 February 1995, the Republic of Azerbaijan and the Republic of Cameroon signed a protocol on the establishment of diplomatic relations4 October 1991Both countries established diplomatic relations on 4 October 199127 February 1975Both countries established diplomatic relations on 27 February 197514 March 1962Both countries established diplomatic relations on 14 March 1962 when has been accredited Ambassador of Belgium to Cameroon with residence in Yaounde Mr. E. Luyckx.31 July 1976Both countries established diplomatic relations on 31 July 197624 February 1984Both countries established diplomatic relations on 24 February 19847 December 1961Cameroon and Canada have established diplomatic ties on 7 December 1961 with three agreements and four protocoles signed in 1965.Both countries share the use of English and French as the two official languages as well as memberships in the Francophonie and The Commonwealth.", "* Cameroon has a high commission in Ottawa.", "* Canada has a high commission in Yaoundé.26 March 1971Both countries established diplomatic relations on 26 March 1971The People's Republic of China has a number of health and infrastructure projects underway in Cameroon.", "In January 2007, China signed a series of economic agreements with Cameroon, giving more than $54 million in loans., China constructed the multipurpose sports complex in Yaounde and renovated the famous Amadou Ahidjo stadium.8 March 1989Both countries established diplomatic relations on 8 March 198929 June 1965Both countries established diplomatic relations on 29 June 196526 November 1962Both countries established diplomatic relations on 26 November 1962 when has been appointed Mr. Emmanuel Samory as Permanent Representative of the Republic of Congo to Cameroon.3 September 1962Both countries established diplomatic relations on 3 September 1962* Cameroon has an embassy in Abidjan.", "* Cote d'Ivoire has an embassy in Yaounde which also functions as the non-resident embassy to Central African Republic.18 October 2002Both countries established diplomatic relations on 18 October 200231 August 1974Both countries established diplomatic relations on 31 August 197422 January 1978Both countries established diplomatic relations on 22 January 19787 January 1961Both countries established diplomatic relations on 7 January 196127 October 1968Both countries established diplomatic relations on 27 October 1968Cameroon has a dispute with Equatorial Guinea over the exclusive maritime economic zone, which is currently before the ICJ.", "They also have a dispute over an island at the mouth of the Ntem River.17 January 1964Both countries established diplomatic relations on 17 January 19641 January 1960Both countries established diplomatic relations on 1 January 1960 Cameroon has particularly close ties with France, with whom it has numerous military, economic, and cultural agreements, the construction of the Bonaberi bridge in Douala is pioneered by the French and they are to exploit uranium discovered in the Nort by 2018.26 February 1975Both countries established diplomatic relations on 26 February 19758 March 1975Both countries established diplomatic relations on 8 March 1975 when Gambia's first Ambassador to Cameroon (resident in Dakar) Mr. Samuel Jonathan Okiki Sarr presented his credentials to President Ahmadou Ahidjo.26 September 2013Both countries established diplomatic relations on 26 September 20131 January 1960Both countries established diplomatic relations on 1 January 196020 August 1963Both countries established diplomatic relations on 20 August 196328 April 1973Both countries established diplomatic relations on 28 April 1973 when the first Greek Ambassador to the Cameroon, Mr. Sathis Mitsopoulos, presented his credentials to President Ahidjo.14 April 1993Both countries established diplomatic relations on 14 April 199311 January 1981Both countries established diplomatic relations on 11 January 1981 when Ambassador of Haiti (with residence in Nigeria) M. Antoine Victor Pierre-Louis has presented his credentials to President of Cameroon M. Ahmadou Ahidjo.20 January 1987Both countries established diplomatic relations on 20 January 198719 September 2007Both countries established diplomatic relations on 19 September 20074 April 1963Both countries established diplomatic relations on 4 April 196316 June 1992Both countries established diplomatic relations on 16 June 199210 March 1975Both countries established diplomatic relations on 10 March 197523 April 2007Both countries established diplomatic relations on 23 April 200715 September 1960Both countries established diplomatic relations on 15 September 1960, but relations was broken on 13 October 1973 and re-established diplomatic relations on 26 August 1986Cameroon's Rapid Reaction Force is trained and armed by Israel, and Cameroon supports Israel in the United Nations General Assembly (UNGA) draft resolution votes.", "Many citizens of Cameroon receive training and education in agriculture in Israel.", "The Israeli ambassador described Cameroon as Israel's best friend in Africa.", "Additionally, Cameroon strongly opposes the existence of and antagonizes Palestine and is one of only two nations in Africa not to have yet recognized it28 February 1962Both countries established diplomatic relations on 28 February 196226 September 1991Both countries established diplomatic relations on 26 September 199114 May 2009Both countries established diplomatic relations on 14 May 20095 September 1972Both countries established diplomatic relations on 5 September 197222 February 1975Both countries established diplomatic relations on 22 February 197527 September 2019Both countries established diplomatic relations on 27 September 201916 April 2015Both countries established diplomatic relations on 16 April 201529 October 1968Both countries established diplomatic relations on 29 October 1968 when first Ambassador of Lesotho to Cameroon Mr. C. D. Molapo has presented his credentials to President Ahidjo23 November 1960Both countries established diplomatic relations on 23 November 1960 when open Embassy of Cameroon in Monrovia.3 August 1969Both countries established diplomatic relations on 3 August 1969.16 October 2013Both countries established diplomatic relations on 16 October 20137 June 1962Both countries established diplomatic relations on 7 June 196210 September 1974Both countries established diplomatic relations on 10 September 19741 March 1991Both countries established diplomatic relations on 1 March 199127 January 2006Both countries established diplomatic relations on 27 January 200622 December 1975Both countries established diplomatic relations on 22 December 1975* Cameroon is accredited to Mexico from its embassy in Washington, D.C., United States with a consulate in Mexico City.", "* Mexico is accredited to Cameroon from its embassy in Abuja, Nigeria with a consulate in Yaoundé.27 March 2019Both countries established diplomatic relations on 27 March 20192 April 2015Both countries established diplomatic relations on 2 April 201513 August 1965Both countries established diplomatic relations on 13 August 19659 December 1975Both countries established diplomatic relations on 9 December 197510 July 1990Both countries established diplomatic relations on 10 July 199022 June 2023Both countries established diplomatic relations on 22 June 20232 December 1961Both countries established diplomatic relations on 2 December 19611 November 2019Both countries established diplomatic relations on 1 November 2019November 1960Both countries established diplomatic relations in November 1960Cameroon is engaged in a sporadic armed conflict with Nigeria in the oil-rich Bakassi Peninsula.", "The dispute was resolved through the 2006 Greentree Agreement which led to the full withdrawal of Nigerian troops from the region and its administrative transfer back to Cameroon in August 2013.The two countries agree on maritime delimitation.Economic relations between both states are however timid, the uprise of the Boko Haram terrorists group called for military co-operation between Cameroon and Nigeria.6 April 2001Both countries established diplomatic relations on 6 April 200115 June 1965Both countries established diplomatic relations on 15 June 196530 November 1998Both countries established diplomatic relations on 30 November 199814 August 1984Both countries established diplomatic relations on 14 August 19843 December 1993Both countries established diplomatic relations on 3 December 199325 April 1964Both countries established diplomatic relations on 25 April 196414 March 1972Both countries established diplomatic relations on 14 March 197212 February 1977Both countries established diplomatic relations on 12 February 197726 February 1975Both countries established diplomatic relations on 26 February 197515 May 1970Both countries established diplomatic relations on 15 May 197020 February 1964Both countries established diplomatic relations on 20 February 1964* Cameroon has an embassy in Moscow.", "* Russia has an embassy in Yaoundé.", "9 June 2021Both countries established diplomatic relations on 9 June 202114 July 1975Both countries established diplomatic relations on 14 July 19751961Both countries established diplomatic relations in 19611960Both countries established diplomatic relations in 196030 September 1976Both countries established diplomatic relations on 30 September 197629 April 1994Both countries established diplomatic relations on 29 April 199410 August 1961Both countries established diplomatic relations on 10 August 1961.In 2012 Bilateral Trade was US$64 million10 November 1961Both countries established diplomatic relations on 10 November 196112 July 1963Both countries established diplomatic relations on 12 July 196320 May 2003Both countries established diplomaticrelations on 20 May 200319 December 1976Both countries established diplomatic relations on 19 December 197618 February 1961Both countries established diplomatic relations on 18 February 1961 9 August 1963Both countries established diplomatic relations on 9 August 1963 when first Ambassador of Turkey to Cameroon Mr. Mustapha Fehmi Nuza presented his credentials to President Ahmadou Ahidjo* Cameroon has an embassy in Ankara*Turkey has an embassy in Yaoundé*Trade volume between the two countries was US$205 million in 2019 (Cameroon's exports/imports: 54/151 million USD).", "*There are direct flights from Istanbul to Yaoundé.7 November 1973Both countries established diplomatic relations on 7 November 1973 when the first Ambassador of Cameroon to Uganda, Haji Mahmoudou Hamman Dick, presented his credentials to President Amin.21 October 1993Both countries established diplomatic relations on 21 October 199324 February 1975Both countries established diplomatic relations on 24 February 19751 January 1960Both countries established diplomatic relations on 1 January 19601 January 1960Both countries established diplomatic relations on 1 January 1960* Cameroon has an embassy in Washington, D.C.* United States has an embassy in Yaoundé.18 December 2017Both countries established diplomatic relations on 18 December 201725 June 1991Both countries established diplomatic relations on 25 June 199130 August 1972Both countries established diplomatic relations on 30 August 1972.Vietnam is represented in Cameroon through a non-resident embassy in Abuja, Nigeria and an honorary consulate in Douala.", "In 2014 Nexttel, Joint operative company of Viettel becomes the First 3G operator in Cameroon.28 February 1991Both countries established diplomatic relations on 28 February 1991." ], [ "Multilateral relations", "In addition to the United Nations, Cameroon is very active in other multilateral organisations or global institutions such as the Organisation internationale de la Francophonie, The Commonwealth, the Organisation of Islamic Cooperation, the Group of 77, the Non-Aligned Movement, the African Union and the Economic Community of Central African States." ], [ "Refugees and internally displaced persons", "Refugees (country of origin): 20,000-30,000 (Chad); 3,000 (Nigeria); 24,000 (Central African Republic) (2007)" ], [ "See also", "* List of diplomatic missions in Cameroon* List of diplomatic missions of Cameroon" ], [ "References" ] ]

[ [ "Geography of Cape Verde" ], [ "Introduction", "The location of Cape Verde.Map of the Cape Verde Islands.Mount Fogo, the highest point in Cabo Verde.Ribeira Torre on Santo Antão Island, Cape Verde.Satellite image of Fogo.", "'''Cape Verde''' (formally, the '''Republic of Cabo Verde''') is a group of arid Atlantic islands which are home to distinct communities of plants, birds, and reptiles.", "The islands constitute the unique Cape Verde Islands dry forests ecoregion, according to the World Wildlife Fund." ], [ "Location and description", "The Cape Verde Islands are located in the mid-Atlantic Ocean some off the west coast of the continent of Africa.", "The landscape varies from dry plains to high active volcanoes with cliffs rising steeply from the ocean.", "The climate is arid.", "The total size is .The archipelago consists of ten islands and five islets, divided into the windward (Barlavento) and leeward (Sotavento) groups.", "The six islands in the Barlavento group are Santo Antão, São Vicente, Santa Luzia, São Nicolau, Sal, and Boa Vista.", "The islands in the Sotavento group are Maio, Santiago, Fogo, and Brava.", "All but Santa Luzia are inhabited.Three islands – Sal, Boa Vista, and Maio – generally are level and lack natural water supplies.", "Mountains higher than are found on Santiago, Fogo, Santo Antão, and São Nicolau.Sand carried by strong winds has caused erosion on all islands, especially the windward ones.", "Sheer, jagged cliffs rise from the sea on several of the mountainous islands.", "The lack of natural vegetation in the uplands and coast also contributes to soil erosion.", "The interior valleys support denser natural vegetation." ], [ "Data", "; Geographic coordinates:: ; Area::* Total: 4,072 km2:* Land: 4,072 km2:* Water: 0 km2 (inland water is negligible) ; Area – comparative:About 1.5 times as large as Luxembourg; Coastline:; Maritime claims::* Measured from claimed archipelagic baselines:* Territorial sea: :* Contiguous zone: :* Exclusive economic zone: ; Exclusive economic zone:* EEZ area: :* Continental shelf: 5,591 km2:* Coral reefs: 0.09% of world:* Sea mounts: 0.04% of world ; Terrain:Steep, rugged, rocky, volcanic.", "; Elevation extremes::* Lowest point: Atlantic Ocean 0 m:* Highest point: Mount Fogo (a volcano on Fogo Island); Natural resources:Salt, basalt rock, limestone, kaolin, fish, clay, gypsum; Land use:* '''agricultural land:''' 18.6% (2018 est.", "):**arable land: 11.7% (2018 est.", "):**permanent crops: 0.7% (2018 est.", "):**permanent pasture: 6.2% (2018 est.", "):*'''forest:''' 21% (2018 est.", "):*'''other:''' 60.4% (2018 est.", "); Irrigated land: (2012); Total renewable water resources:0.3 km3 (2017); Freshwater withdrawal (domestic/industrial/agricultural):* total: 0.02 km3/yr (6%/1%/93%):* per capita: 48.57 m3/yr (2004); Natural hazards:: Prolonged droughts; seasonal harmattan wind produces obscuring dust; volcanically and seismically active.", "; Geography - note:: Strategic location 500 km from west coast of Africa near major north-south sea routes; important communications station; important sea and air refueling site." ], [ "Table of islands", "Island or islet Largest Settlement Other Settlements Area (km2) PopulationBarlavento Islands 2265.55 179114Santo Antão Porto NovoRibeira Grande, Pombas, Ponta do Sol779.0 46872São Vicente Mindelo 227.0 81267Ilhéu dos Pássaros uninhabited 0.05 0Santa Luzia uninhabited 34.0 0Ilhéu Raso 7.0 0Ilhéu Branco 3.00São Nicolau Ribeira BravaTarrafal de São Nicolau 379.5 13680Sal EspargosSanta Maria216.0 27515Boa Vista Sal ReiEstância de Baixo620.0 9779Sotavento Islands 1806.95 345886Maio Vila do MaioCalheta269.0 7420Santiago PraiaAssomada, Tarrafal, Calheta de São Miguel, Pedra Badejo, Cidade Velha991.0 292500Fogo São FilipeMosteiros, Cova Figueira475.6 39567Brava Nova SintraFurna66.66399Ilhéus Secos uninhabited 4.750" ], [ "Borders", "Map of Cape Verde's EEZ.Cabo Verde shares maritime boundaries with Mauritania and Senegal.", "Cabo Verde has signed treaties with Senegal and Mauritania delimiting the specific boundaries.", "However, the two treaties conflict in their delimitation of the precise borders.", "Due to the numerous islands it has an Exclusive Economic Zone of ." ], [ "Climate", "Rainfall is irregular, historically causing periodic droughts and famines.", "Desalination plants now provide water to more than half the country's population.", "Experiments with fog collectors have been conducted since 1962, however, such collectors had not been expanded beyond the Serra Malagueta community of Santiago Island, as of 2009.The average precipitation per year in Praia is .During the winter, storms blowing from the Sahara sometimes cloud the sky; however, sunny days are the norm year round.", "The clearest skies are found between February and June, with very little rainfall during these months.", "Saharan dust, Harmattan wind, laden with dust come from the Sahara.", "This occurs between November and March and is generally similar to the \"Calima\" affecting the Canary Islands.The ocean near Cabo Verde is an area of tropical cyclone formation; since these storms have the whole Atlantic over which to develop as they move westward, they are among the most intense hurricanes, and are called Cape Verde-type hurricanes.The Cape Verde islands are a very degradated area.", "Also, most islands do not always get a monsoon.", "In fact, it is not surprising that some atmospheric precipitation of islands are limited in tropical rain.If rain arrives, it is usually between August and October.", "The first \"rainy season\" brings high temperatures and high humidity that condenses as dew mountain.", "The other rainy season is between December and June, when the northeast trade winds are common during this season, only altitudes above 600 m tend to receive regular rain.The island of Sal receives an average of 0 mm in May.", "When the rain comes, if it comes, it can be very strong.", "Half of the rain in a particular year can often fall into a single storm.Most of the Cape Verde islands are dry, but on islands with high mountains and farther away from the continental land mass, by orography, the humidity is much higher, giving a rainforest habitat, very degraded by the strong human presence.Northeastern slopes of high mountains often receive a lot of rain and southwestern slopes do not.", "This is because they are umbria areas, situated in the north hillsides or slopes of the mountainous areas, oriented behind the Sun in the Northern Hemisphere, in the shadyside orographic.", "So the amount of solar radiation that it receive is much lower than it would if it had without the island's relief which intercepts much of the sunlight.", "In terms of botanical ecology, these umbria areas are identified as being cool and moist.The current north of the Canaries, has a cooling effect on the islands of Cabo Verde, making the air temperature more bearable than it would expect in any case at this latitude.", "Conversely, the islands do not receive the upwellings (cold streams) that affect the West African coast, so the air temperature is cooler than in Senegal, but the sea is actually warmer, because the orographic relief of some islands, such as Sao Miguel with steep mountains, cover it with rich woods and luxuriant vegetation where the humid air condenses and soak the plants, rocks, soil, logs, and moss.Hurricanes often begin forming in the waters around the islands of Cabo Verde, but it is rare that the strength of the storm reaches close to the islands.", "A Cape Verde type hurricane is formed in the area south of the islands, near Sao Miguel, after a tropical wave on the African continent during the rainy season.", "The storm picks up strength when it crosses the warm waters of Atlantic.Fog on Cape VerdeThe laurel forest is a type of cloud forest, the cloud forests, are developed preferably about mountains, where the dense moisture from the sea or ocean, is precipitated by the action of the relief.", "Opposing the terrain to a front of warm, moist air mass, it forces to increase the height above sea level of that body wet and warm air mass, which cools and decreases the dew point, causing it to condense part of the moisture that falls as rain or fog, creating a habitat especially cool, saturated with moisture in the air and soil.It is the balance between the dry and warm influence of the subtropical anticyclone, hot and dry summer and orography the responsible for carrying cool wet air.As latitude increases, this increases the impact of the storms, which in its journey from west to east, swept the western coasts of continents, dumping heavy rains as carrying high humidity.Precipitation multiply if these air masses are crossing mountains in the way.", "The resulting climate is wetter, but with an annual oscillation of the temperature moderated by the proximity of the ocean.Appear mostly occupying favorable areas named geographically Umbrias, this is north hillsides or slopes of the mountainous areas that are oriented behind the sun, because the islands are in the Northern Hemisphere, between 600 and 1,500 meters, thus benefiting from the humidity provided by the trade winds to form such a sea of clouds.", "In its botanical ecology, the mountain umbria is identified with cool and moisture." ], [ "Flora", "Cape Verde is the driest archipelago of the ecoregion of Macaronesia.", "That with a greater influence of African species due to its geographical location near the African mainland of the Sahel.At first, the islands of Cabo Verde housed an extensive savanna and dry forest cover, but mostly it was removed to convert to agricultural land, which, together with the arid climate and rugged terrain, has led to a soil erosion and desertification widespread.", "However, the archipelago can be divided into four broad ecological zones (arid, semiarid, subhumid and humid), according to altitude and average annual rainfall ranging from 200 mm in the arid areas of the coast to more than 1000 mm in the humid mountain.", "Mostly rainfall precipitation is due to condensation of the ocean mist.", "Today much of the forest cover comprises relatively immature agroforestry plantations, in which are used non-native species such as Prosopis juliflora, Leucaena leucocephala and Jatropha curcas.", "The native laurel forest species are in wet area only in mountainous areas.On the lower and drier islands the vegetation, before human colonization, consisted of savanna or steppe vegetation, with the flattest inland portion supporting semi-desert plants.", "At higher altitudes, a form of arid shrubland was also present.", "These islands were covered with savanna on the plains and arid shrubland on the mountainsides, but after over 500 years of human habitation (after Portuguese colonisation) nearly all the original vegetation has been cleared in favour of widespread agriculture including the grazing of goats, sheep and cattle and the planting of imported crop species.", "There are some remaining patches of dry forest high on steep mountainside including a number of endemic plant species, but these are inaccessible and hard to study.On the higher islands and somewhat wetter islands, exclusively in mountainous areas, like Santo Antao island, the climate is suitable for the development of dry monsoon forest, and laurel forest as this vegetation is believed to have been present in the past.", "However, most vegetation has now been converted to agriculture and forest fragments are now restricted to areas where cultivation is not possible, such as mountain peaks and steep slopes.", "The demand for wood has resulted in deforestation and desertification.Of particular note is the endemic type of humid subtropical laurel forest of macaronesian laurisilva, found on several of the Macaronesian African mainland enclaves and Macaronesian islands of the North Atlantic, namely Madeira Islands, the Azores, Cape Verde Islands, and the Canary Islands; these are a relic of the Pliocene subtropical forests, supporting numerous endemic species.This laurisilva forests are found in the islands of Macaronesia in the eastern Atlantic, in particular the Azores, Madeira Islands, and western Canary Islands, from 400 m to 1,200 m elevation.", "Trees of the genera ''Apollonias'' (Lauraceae), ''Ocotea'' (Lauraceae), ''Persea'' (Lauraceae), ''Clethra'' (Clethraceae), ''Dracaena'' (Ruscaceae), and ''Picconia'' (Oleaceae) are characteristic.", "The Madeira Islands laurel forest was designated a World Heritage Site by UNESCO in 1999." ], [ "Fauna", "There are four endemic bird species including the Raso lark along with more common swifts, larks, warblers, and sparrows.", "The islands are an important breeding site for seabirds including the Cape Verde shearwater and Fea's petrel (''Pterodroma feae''), which breeds only here and in Madeira.", "Santiago Island holds the only breeding site of the endemic and critically endangered Bourne's heron.", "The 11 endemic reptile species include a giant gecko (''Tarentola gigas''), and there are other geckos and skinks in abundance.", "The giant skink (''Macroscincus coctei'') is now thought to be extinct." ], [ "Threats and protection", "Almost all of the natural environment has been destroyed by conversion to agriculture and logging for firewood, as well as natural soil erosion, all of which has threatened several species of birds and reptiles.", "The remaining original forest exists at high altitudes only.", "Newer problems include illegal beach sand extraction and overfishing while the nesting birds are vulnerable due to introduced mammals, including cats and rats.", "; Environment - international agreements:* Party to: Biodiversity, Climate Change, Climate Change-Kyoto Protocol, Climate Change-Paris Agreement, Comprehensive Nuclear Test Ban, Desertification, Endangered Species, Environmental Modification, Hazardous Wastes, Law of the Sea, Marine Dumping, Nuclear Test Ban, Ozone Layer Protection, Ship Pollution, Wetlands" ], [ "Extreme points", "* Northernmost point - Ponta do Sol on Santao Antão Island* Southernmost point - Ponta Nho Martinho on Brava* Westernmost point - Ponta Chao de Mongrade on Santao Antão** Easternmost point - Ponta Meringuel on Boa Vista* *''Note: this is also the westernmost point of Africa''" ], [ "References", "* *" ] ]

[ [ "Demographics of Cape Verde" ], [ "Introduction", " Demographic features of the population of Cape Verde include population density, ethnicity, education level, health of the populace, economic status, religious affiliations and other aspects of the population.Cape Verde has a population of about 540,000 inhabitants who live in the islands.", "A large proportion (236,000) of Cape Verdeans live on the main island, Santiago.", "Many more live abroad in the Cape Verdean diaspora in mainland Africa, Europe, U.S., Brazil, et cetera.The archipelago of Cape Verde were first found and claimed by Portuguese sailors working for the Portuguese Crown in 1456.Cape Verdeans are West African.", "Many foreigners from other parts of the world settled in Cape Verde as their permanent country.", "Two Cape Verdean children playingSurvival in a country with few natural resources has historically induced Cape Verdeans to emigrate.", "In fact, of the more than 1 million people of Cape Verdean ancestry in the world, only a little more than one-third actually live on the islands.", "Some 500,000 people of Cape Verdean ancestry live in the United States, mainly in New England.", "Many people of Cape Verdean ancestry also live in Portugal, Netherlands, France, Italy and Senegal.", "Cape Verdean populations also settled Spain, Germany, Canada, and other CPLP countries (Angola, Brazil and Guinea-Bissau).", "Since independence from Portugal in 1975, a number of Cape Verdean students continued to be admitted every year at Portuguese high schools, polytechnical institutes and universities, through bilateral agreements between the Portuguese and Cape Verdean governments.Portuguese functions as a state language.", "Virtually all formal documents and official declarations are stated in Portuguese.", "But it is not the first language.", "Cape Verdean, commonly called Kriolu, is spoken as a mother tongue by virtually all Cape Verdeans, irrespective of social status or religious affiliation.", "Moreover, historical linguists often attribute Cape Verdean Creole as the oldest \"New World\" contact language.", "It is a \"contact\" language in the sense that it was birthed and evolved between linguistically different groups who, by necessity, had to create a common language to communicate with each other.", "There is a rich repertoire of literature and songs in Cape Verdean Creole.", "In religion, the majority of Cape Verdeans follow Catholic Christianity.", "There are some Protestants, Baháʼís and Muslims." ], [ "Population", "FAO, year 2005 ; Number of inhabitants in thousands.According to the total population was in , compared to only 178,000 in 1950.The proportion of children below the age of 15 in 2010 was 31.8%, 62.3% was between 15 and 65 years of age, while 5.9% was 65 years or older.Total populationPopulation aged 0–14 (%)Population aged 15–64 (%)Population aged 65+ (%) 1950 178,00032.659.87.6 1955 195,00035.857.96.2 1960 211,00042.153.24.8 1965 240,00048.547.34.2 1970 274,00048.247.84 1975 311,00045.849.64.6 1980 300,0004648.75.3 1985 328,00044.550.55 1990 348,00045.449.84.8 1995 395,00044.550.55 2000 437,00041.752.95.3 2005 473,0003757.25.8 2010 496,00031.862.35.9Age GroupMaleFemaleTotal% Total 243 403 248 280 491 683 100 0–4 25 131 25 069 50 200 10.21 5–9 25 168 25 040 50 208 10.21 10–14 27 864 27 361 55 225 11.23 15–19 29 655 29 405 59 060 12.01 20–24 27 327 25 578 52 905 10.76 25–29 23 336 21 005 44 341 9.02 30–34 18 165 16 339 34 504 7.02 35–39 14 106 13 130 27 236 5.54 40–44 12 988 13 303 26 291 5.35 45–49 11 347 12 165 23 512 4.78 50–54 8 162 9 999 18 161 3.69 55–59 4 947 7 196 12 143 2.47 60–64 2 613 3 580 6 193 1.26 65-69 2 499 3 716 6 215 1.26 70-74 3 437 5 229 8 666 1.76 75-79 2 980 4 453 7 433 1.51 80-84 2 092 3 185 5 277 1.07 85-89 827 1 358 2 185 0.44 90-94 377 696 1 073 0.22 95+ 172 325 497 0.10Age group MaleFemaleTotalPercent 0–14 78 163 77 470 155 633 31.65 15–64 152 646 151 700 304 346 61.90 65+ 12 384 18 962 31 346 6.38 Unknown 210 148 358 0.07Age GroupMaleFemaleTotal% Total 281 533 275 324 556 857 100 0–4 26 739 25 524 52 264 9.39 5–9 26 162 24 973 51 135 9.18 10–14 25 262 25 389 50 651 9.10 15–19 23 734 23 483 47 218 8.48 20–24 23 955 22 461 46 416 8.34 25–29 28 159 26 015 54 173 9.73 30–34 28 603 24 995 53 597 9.62 35–39 24 111 20 484 44 595 8.01 40–44 18 738 15 923 34 660 6.22 45–49 14 043 12 780 26 822 4.82 50–54 12 282 12 693 24 974 4.48 55–59 10 437 11 557 21 994 3.95 60–64 7 125 9 226 16 351 2.94 65-69 4 080 6 402 10 482 1.88 70-74 2 050 2 955 5 006 0.90 75-79 1 722 2 772 4 494 0.81 80-84 2 037 3 496 5 533 0.99 85-89 1 443 2 389 3 833 0.69 90-94 682 1 249 1 931 0.35 95+ 170 560 730 0.13Age group MaleFemaleTotalPercent 0–14 78 163 75 886 154 049 27.66 15–64 191 186 179 615 370 801 66.59 65+ 12 184 19 823 32 007 5.75Age GroupMaleFemaleTotal% Total 246 363 244 870 491 233 100 0–4 23 111 22 429 45 540 9.27 5–9 23 533 23 086 46 619 9.49 10–14 23 809 22 771 46 580 9.48 15–19 21 903 20 401 42 304 8.61 20–24 20 391 18 159 38 550 7.85 25–29 22 481 21 665 44 146 8.99 30–34 22 552 21 681 44 233 9.00 35–39 19 217 18 105 37 322 7.60 40–44 15 820 14 259 30 079 6.12 45–49 12 269 11 347 23 616 4.81 50–54 11 257 11 224 22 481 4.58 55–59 10 001 10 682 20 683 4.21 60–64 7 536 8 765 16 301 3.32 65-69 4 496 6 510 11 006 2.24 70-74 2 347 3 279 5 626 1.15 75-79 1 685 2 842 4 527 0.92 80-84 1 839 3 404 5 243 1.07 85-89 1 257 2 473 3 730 0.76 90-94 648 1 316 1 964 0.40 95+ 211 472 683 1.39Age group MaleFemaleTotalPercent 0–14 70 453 68 286 138 739 28.24 15–64 163 427 156 288 319 715 65.08 65+ 12 483 20 296 32 779 6.67" ], [ "Vital statistics", "Vital events of Cape Verde are not (yet) available for recent years.", "The Population Department of the United Nations prepared the following estimates.PeriodLive births per yearDeaths per yearNatural change per yearCBR*CDR*NC*TFR*IMR* 1950-1955 9 000 4 000 5 00049.022.626.36.57139 1955-1960 10 000 4 000 5 00048.021.126.96.76132 1960-1965 10 000 4 000 6 00045.018.726.36.97125 1965-1970 11 000 4 000 6 00041.416.425.06.97117 1970-1975 12 000 4 000 8 00041.113.427.76.8696 1975-1980 13 000 4 000 9 00041.611.630.06.6278 1980-1985 13 000 3 000 10 00041.310.331.06.1065 1985-1990 14 000 3 000 11 00040.99.231.75.6354 1990-1995 14 000 3 000 11 00036.57.928.64.9344 1995-2000 13 000 3 000 10 00031.66.724.94.1537 2000-2005 12 000 3 000 9 00026.25.820.53.2828 2005-2010 11 000 3 000 8 00021.95.216.72.6021 * CBR = crude birth rate (per 1000); CDR = crude death rate (per 1000); NC = natural change (per 1000); IMR = infant mortality rate per 1000 births; TFR = total fertility rate (number of children per woman)===Births and deaths===YearPopulationLive birthsDeathsNatural increaseCrude birth rateCrude death rateRate of natural increaseTFR 1948 3,756 1949 3,904 3,641 263 1950 5,322 2,562 2,760 1951 7,367 2,377 4,990 1952 7,647 2,455 5,192 1953 7,597 2,866 4,731 1954 8,697 3,305 5,392 1955 8,547 2,220 6,327 1956 8,377 2,200 6,177 1957 8,237 2,790 5,447 1958 9,026 2,552 6,474 1959 9,609 2,382 7,227 1960 8,954 3,127 5,827 1961 8,319 2,543 5,776 1962 8,952 2,452 6,500 1963 9,671 2,996 6,675 1964 9,783 2,315 7,468 1965 9,638 2,377 7,261 1966 9,621 2,167 7,454 1967 10,190 2,593 7,597 1968 10,131 2,397 7,734 1969 9,671 3,452 6,219 1970 9,379 2,883 6,496 1971 9,493 4,147 5,346 1972 8,966 2,779 6,187 1973 8,418 3,513 4,905 1974 8,492 2,576 5,916 1975 8,210 2,796 5,414 1976 9,863 2,869 6,994 1977 9,965 2,564 7,401 1978 10,060 3,207 6,853 1979 8,289 2,469 5,820 1980 9,650 2,080 7,570 1981 8,580 1982 11,066 2,169 8,897 1983 11,438 2,649 8,789 1984 11,696 2,863 8,833 1985 11,282 2,735 8,547 1986 12,636 1987 12,771 1988 12,443 1989 1990 9,669 2,505 7,164 1991 12,289 2,616 9,673 1992 9,671 2,843 6,828 1993 2,821 1994 1995 386,813 3,520 9.1 1996 393,478 2,715 6.9 1997 406,267 3,047 7.5 1998 413,382 15,460 2,811 12,649 6.8 1999 426,061 2,812 6.6 2000 436,821 12,746 2,433 10,313 29.2 5.6 23.6 4.00 2001 445,035 12,550 2,396 10,154 28.2 5.4 22.8 2002 452,198 12,345 2,395 9,950 27.3 5.3 22.0 2003 460,837 12,120 2,600 9,520 26.3 5.6 20.7 2004 468,854 11,862 2,522 9,340 25.3 5.4 19.9 2005 478,163 11,554 2,423 9,131 24.3 5.1 19.2 2006 487,121 9,765 2,612 7,153 20.7 5.4 15.3 2.44 2007 491,419 10,421 2,484 7,937 21.8 5.2 16.6 2.57 2008 499,796 10,165 2,683 7,482 21.0 5.5 15.5 2.43 2009 485,677 9,962 2,583 7,379 20.4 5.3 15.1 2.33 2010 491,683 10,568 2,352 8,216 21.4 4.8 16.6 2.42 2011 499,929 10,777 2,488 8,289 21.6 5.0 16.6 2.44 2012 505,983 10,050 2,610 7,440 19.9 5.2 14.7 2.26 2013 512,173 9,845 2,518 7,327 19.2 4.9 14.3 2.19 2014 518,467 9,868 2,528 7,340 19.0 4.9 14.1 2.17 2015 524,833 9,757 2,761 6,996 18.6 5.3 13.3 2.11 2016 531,239 9,935 2,591 7,344 18.7 4.9 13.8 2.13 2017 537,661 9,899 2,497 7,402 18.4 4.6 13.6 2.11 2018 544,081 9,480 2,836 6,588 17.4 5.2 12.2 1.98 2019 9,154 2,771 6,383 16.6 5.0 11.6 2020 8,944 2,959 5,985 16.1 5.3 10.8 2021 7,632 3,178 4,454 13.6 5.6 8.0 ===Fertility and births===Total fertility rate (TFR) (wanted fertility rate) and crude birth rate (CBR): Year CBR (Total) TFR (Total) CBR (Urban) TFR (Urban) CBR (Rural) TFR (Rural) 2005 22 2,9 (2,8) 23 2,7 (2,7) 22 3,1 (3,0)Fertility data from 2005 (DHS Program): Region Total fertility rate Percentage of women age 15-49 currently pregnant Mean number of children ever born to women age 40-49 Santo Antão 2.9 3.8 6.0 São Vicente 2.0 3.4 4.0 São Nicolau 3.3 4.4 4.2 Sal 3.2 7.0 3.9 Boa Vista 2.4 10.0 4.4 Maio 2.6 1.7 4.3 Santiago 3.1 5.4 4.5 Praia Urbano 3.2 5.1 4.5 Santiago Norte 2.7 6.2 4.3 Resto Santiago 3.3 4.6 4.8 Fogo 3.1 6.3 5.6 Brava 2.8 7.0 5.0=== Life expectancy ===PeriodLife expectancy in Years1950–195548.081955–1960 48.77 1960–1965 49.45 1965–1970 52.43 1970–1975 55.25 1975–1980 60.52 1980–1985 62.37 1985–1990 64.10 1990–1995 65.73 1995–2000 67.94 2000–2005 71.27 2005–2010 71.77 2010–2015 72.14" ], [ "Other demographic statistics", "Demographic statistics according to the World Population Review in 2022.", "*One birth every 51 minutes\t*One death every 160 minutes\t*One net migrant every 480 minutes\t*Net gain of one person every 90 minutesThe following demographic statistics are from the CIA World Factbook.===Population===:596,707 (2022 est.", "):568,373 (July 2018 est.", ")===Age structure===Population pyramid of Cape Verde in 2020:''0-14 years:'' 27.95% (male 82,010/female 81,012):''15-24 years:'' 18.69% (male 54,521/female 54,504):''25-54 years:'' 40.76% (male 115,811/female 121,923):''55-64 years:'' 7.12% (male 18,939/female 22,597):''65 years and over:'' 5.48% (male 12,037/female 19,901) (2020 est.", "):''0-14 years:'' 28.7% (male 82,035 /female 81,082):''15-24 years:'' 19.64% (male 55,811 /female 55,798):''25-54 years:'' 40.02% (male 110,646 /female 116,804):''55-64 years:'' 6.4% (male 16,154 /female 20,245):''65 years and over:'' 5.24% (male 11,272 /female 18,526) (2018 est.", ")===Median age===:total: 26.8 years.", "Country comparison to the world: 151st:male: 25.9 years:female: 27.6 years (2020 est.", "):total: 25.8 years.", "Country comparison to the world: 153rd:male: 25 years :female: 26.7 years (2018 est.", "):Total: 23.1 years:Male: 22.3 years:Female: 23.9 years (2012 est.", ")===Population growth rate===:1.21% (2022 est.)", "Country comparison to the world: 76th:1.32% (2018 est.)", "Country comparison to the world: 83rd===Total fertility rate===:2.13 children born/woman (2022 est.)", "Country comparison to the world: 92nd:2.21 children born/woman (2018 est.)", "Country comparison to the world: 95th===Birth rate===:18.49 births/1,000 population (2022 est.)", "Country comparison to the world: 79th:19.7 births/1,000 population (2018 est.)", "Country comparison to the world: 79th===Death rate===:5.8 deaths/1,000 population (2022 est.)", "Country comparison to the world: 168th:6 deaths/1,000 population (2018 est.)", "Country comparison to the world: 163rd===Net migration rate===:-0.57 migrant(s)/1,000 population (2022 est.)", "Country comparison to the world: 126th:-0.6 migrant(s)/1,000 population (2017 est.)", "Country comparison to the world: 128th===Urbanization===:urban population: 67.5% of total population (2022):rate of urbanization: 1.83% annual rate of change (2020-25 est.", "):urban population: 65.7% of total population (2018):rate of urbanization: 1.97% annual rate of change (2015-20 est.", ")===Contraceptive prevalence rate===:55.8% (2018)===Sex ratio===:At birth: 1.03 male(s)/female:Under 15 years: 1.01 male(s)/female:15-64 years: 0.97 male(s)/female:65 years and over: 0.58 male(s)/female:Total population: 0.95 male(s)/female (2009 est.", ")===Life expectancy at birth===:total population: 73.75 years.", "Country comparison to the world: 144th:male: 71.41 years:female: 76.15 years (2022 est.", "):total population: 72.7 years (2018 est.", "):male: 70.3 years (2018 est.", "):female: 75.1 years (2018 est.)", "Country comparison to the world: 147th:Total population: 71 years:Male: 68.78 years:Female: 73.27 years (2012 est.", ")===HIV/AIDS===:Adult prevalence rate: 0.035% (2001 est.", "):People living with HIV/AIDS: 775 (2001):Deaths: 225 (as of 2001)===Genetics===E1b1a, R1b:The predominance of West African mitochondrial DNA haplotypes in their maternal gene pool, the major West African Y-chromosome lineage E3a was observed only at a frequency of 15.9%.", "Overall, these results indicate that gene flow from multiple sources and sex-specific patterns have been important in the formation of the genomic diversity in the Cabo Verde islands.===Religions===:Catholic 77.3%, Protestant 3.7% (includes Church of the Nazarene 1.7%, Adventist 1.5%, Universal Kingdom of God 0.4%, and God and Love 0.1%), other Christian 4.3% (includes Christian Rationalism 1.9%, Jehovah's Witness 1%, Assembly of God 0.9%, and New Apostolic 0.5%), Islam 1.8%, Other 1.3%, None 10.8%, Unspecified 0.7% (2010 estimate) ===Languages===:Portuguese (official), Kriolu===Literacy===:Definition: age 15 and over can read and write:Total population: 76.6%:Male: 85.8%:Female: 69.2% (2003 est.", ")===School life expectancy (primary to tertiary education)===:total: 13 years:male: 12 years:female: 13 years (2018):total: 12 years (2017):male: 12 years (2017):female: 12 years (2017)===Dependency ratios===:total dependency ratio: 55.4 (2015 est.", "):youth dependency ratio: 48.4 (2015 est.", "):elderly dependency ratio: 6.9 (2015 est.", "):potential support ratio: 14.4 (2015 est.)" ], [ "See also" ], [ "References" ], [ "External links", "* National Institute of Statistics* Demographic Highlights — Statistics from the Population Reference Bureau" ] ]

[ [ "Politics of Cape Verde" ], [ "Introduction", "'''Politics of Cape Verde''' takes place in a framework of a semi-presidential representative democratic republic, whereby the Prime Minister of Cape Verde is the head of government and the President of the Republic of Cape Verde is the head of state, and of a multi-party system.", "Executive power is exercised by the president and the government.", "Legislative power is vested in both the government and the National Assembly.", "The judiciary is independent of the executive and the legislature.The constitution, first approved in 1980 and substantially revised in 1992, forms the basis of government organization.", "It declares that the government is the \"organ that defines, leads, and executes the general internal and external policy of the country\" and is responsible to the National Assembly.267x267px" ], [ "Political conditions", "Following independence in 1975, the African Party for the Independence of Guinea and Cape Verde (PAIGC) established a one-party political system.", "This became the African Party for the Independence of Cape Verde (PAICV) in 1980, as Cape Verde sought to distance itself from Guinea-Bissau, following unrest in that country.In 1991, following growing pressure for a more pluralistic society, multi-party elections were held for the first time.", "The opposition party, the Movement for Democracy (''Movimento para a Democracia'', MpD), won the legislative elections, and formed the government.", "The MpD candidate also defeated the PAICV candidate in the presidential elections.", "In the 1996 elections, the MpD increased their majority, but in the 2001 the PAICV returned to power, winning both the Legislative and the Presidential elections.Generally, Cape Verde enjoys a stable democratic system.", "The elections have been considered free and fair, there is a free press, and the rule of law is respected by the State.", "In acknowledgment of this, Freedom House granted Cape Verde two first places in its annual Freedom in the World report, a perfect score.", "It is the only African country to receive this score.", "The Prime Minister is the head of the government and as such proposes other ministers and secretaries of state.", "The Prime Minister is nominated by the National Assembly and appointed by the President.", "The President is the head of state and is elected by popular vote for a five-year term; the most recent elections were held in 2021.Also in the legislative branch, the National Assembly (''Assembleia Nacional'') has 72 members, elected for a five-year term by proportional representation.Movement for Democracy (MpD) ousted the ruling African Party for the Independence of Cape Verde (PAICV) for the first time in 15 years in the 2016 parliamentary election.", "The leader of MpD, Ulisses Correia e Silva has been prime minister since 2016.Jorge Carlos Almeida Fonseca was elected president in August 2011 and re-elected in October 2016.He is also supported by MpD.In April 2021, the ruling centre-right Movement for Democracy (MpD) of Prime Minister Ulisses Correia e Silva, won the parliamentary election.", "In October 2021, opposition candidate and former prime minister, José Maria Neves of PAICV, won Cape Verde's presidential election.", "On 9 November 2021, José Maria Neves was sworn in as the new President of Cape Verde." ], [ "Political parties and elections" ], [ "Courts and criminal law", "The judicial system is composed of the Supreme Court and the regional courts.", "Of the five Supreme Court judges, one is appointed by the President, one by the National Assembly, and three by the Superior Judiciary Council.", "This council consists of the President of the Supreme Court, the Attorney General, eight private citizens, two judges, two prosecutors, the senior legal inspector of the Attorney General's office, and a representative of the Ministry of Justice.", "Judges are independent and may not belong to a political party.", "In October 2000, a female judge who was known for taking strict legal measures in cases of domestic violence was transferred from the capital to the countryside.", "Separate courts hear civil, constitutional and criminal cases.", "Appeal is to the Supreme Court.", "Reforms to strengthen an overburdened judiciary were implemented in 1998.Free legal counsel is provided to indigents, defendants are presumed innocent until proven guilty, and trials are public.", "Judges must lay charges within 24 hours of arrests.", "The Constitution provides for an independent judiciary, and the government generally respects this provision in practice.", "The constitution provides for the right to a fair trial and due process, and an independent judiciary usually enforces this right.", "Unlike in the previous year, there were no reports of politicization and biased judgement in the judiciary.", "Cases involving former public office holders still are under investigation.", "For example, investigations continued in the case of the former prime minister accused of embezzlement in the privatization of ENACOL (a parastatal oil supply firm) in which he allegedly embezzled approximately $16,250 (2 million Cape Verdean escudos) from the buyers of the parastatal.", "The case of four persons accused of church desecration in 1996 also was under investigation.", "These individuals filed a complaint with the Attorney General against the judiciary police for alleged fabrication of evidence.The constitution provides for the right to a fair trial.", "Defendants are presumed to be innocent; they have the right to a public, non-jury trial; to counsel; to present witnesses; and to appeal verdicts.", "Regional courts adjudicate minor disputes on the local level in rural areas.", "The Ministry of Justice does not have judicial powers; such powers lie with the courts.The judiciary generally provides due process rights; however, the right to an expeditious trial is constrained by a seriously overburdened and understaffed judicial system.", "A backlog of cases routinely leads to trial delays of 6 months or more; more than 10,780 cases were pending at year's end.", "In addition the right of victims to compensation and recovery for pain and mental suffering are overlooked, due both to the low damage assessments imposed and ineffective enforcement of court sentences." ], [ "Administrative divisions", "Cape Verde is divided into 22 municipalities (concelhos, singular - concelho): Boa Vista, Brava, Maio, Mosteiros, Paul, Porto Novo, Praia, Ribeira Grande, Ribeira Grande de Santiago, Sal, Santa Catarina, Santa Catarina do Fogo, Santa Cruz, São Domingos, São Filipe, São Lourenço dos Órgãos, São Miguel, São Nicolau, São Salvador do Mundo, São Vicente, Tarrafal, Tarrafal de São Nicolau." ], [ "Voting rights for non citizens", "Article 24 of the Cape Verde Constitution states that *alinea 3.: \"''Rights not conferred to foreigners and apatrids may be attributed to citizens of countries with Portuguese as an official language, except for access to functions of sovereignty organs, service in the armed forces or in the diplomatic career.", "''\"*alinea 4.", "\"''Active and passive electoral capacity can be attributed by law to foreigners and apatrid residents on the national territory for the elections of the members of the organs of the local municipalities.", "''\"The website of the governmental Institute of Cape Verde Communities states that such a measure was adopted \"''to stimulate reciprocity from host countries of Cape Verdian migrants''\".A law nr.", "36/V/97 was promulgated on August 25, 1997 regulating the \"Statute of Lusophone Citizen\", concerning nationals from any country member of the Community of Portuguese Language Countries (article 2), stating in its article 3 that \"''The lusophone citizen with residence in Cape Verde is recognized the active and passive electoral capacity for municipal elections, under conditions of the law.", "The lusophone citizen with residence in Cape Verde has the right to exercise political activity related to his electoral capacity.''\"" ], [ "International organization participation", "ACCT, ACP, AfDB, AU, CCC, ECA, ECOWAS, FAO, G-77, IBRD, ICAO, ICRM, IDA, IFAD, IFC, IFRCS, ILO, IMF, IMO, Intelsat, Interpol, IOC, IOM (observer), ITU, ITUC, NAM, OAU, OPCW, UN, UNCTAD, UNESCO, UNIDO, UPU, WHO, WIPO, WMO, WTO (applicant)" ], [ "Sources" ], [ "External links", "* Government of Cape Verde* National Assembly of Cape Verde* Official site of the President of Cape Verde * Chief of State and Cabinet Members* Supreme Court* EU Relations with Cape Verde" ] ]

[ [ "Transport in Cape Verde" ], [ "Introduction", "Most transportation in Cape Verde is done by air.", "There are regular flights between the major islands (Santiago, Sal and São Vicente), with less frequent flights to the other islands.", "Boat transportation is available, though not widely used nor dependable.", "In the major cities, public bus transport runs periodically, and taxis are common.", "In smaller towns, there are mostly hiaces and/or taxis." ], [ "Types of transport", "'''Railways:'''0 km - There are no railways in Cape Verde.", "There was a short overhead conveyor system for salt from the open salt lake on Sal to the port at Pedra de Lume, and a short rail track to the pier at Santa Maria for similar purposes.", "Both are now disused.", "'''Roadways:'''''total:''10,000 km including unpaved tracks accessible only to four wheel drive vehicles''asphalt:''360 km''cobbled:''5,000 km (2007 estimates)The majority of Cape Verdean roads are paved with cobblestones cut from local basalt.", "Recent international aid has allowed the asphalting of many roads including all of the highway between Praia and Tarrafal, all of the highway between Praia and Cidade Velha, and all of the highway between Praia, Pedra Badejo, and Calheta de São Miguel on Santiago, and the dual carriageway between Santa Maria and Espargos on Sal.", "A new ring road has been built from Praia International Airport around the city of Praia.", "The primary method of intercity and inter-village transport for Cape Verdeans is by aluguer shared taxis, commonly called ''Yasi'', which is a derived from the name HiAce, because the Toyota HiAce is the most common shared taxi model.", "Few Cape Verdeans own cars, but ownership is rising rapidly with increasing prosperity, particularly on Santiago Island.An alternative route in Sao Domingos, Cape Verde'''Ports and harbours:''' Mindelo on São Vicente is the main port for cruise liners and the terminus for the ferry service to Santo Antão.", "A marina for yachts is undergoing enlargement (2007).", "Praia on Santiago is a main hub for ferry service to other islands.", "Palmeira on Sal supplies fuel for the main airport on the island, Amílcar Cabral International Airport, and is important for hotel construction on the island.", "Porto Novo on Santo Antão is the only source for imports and exports of produce from the island as well as passenger traffic since the closure of the airstrip at Ponta do Sol.", "There are smaller harbours, essentially single jetties at Tarrafal on São Nicolau, Sal Rei on Boa Vista, Vila do Maio (Porto Inglês) on Maio, São Filipe on Fogo and Furna on Brava.", "These are terminals for inter island ferry service carrying freight and passengers.", "There are small harbours, with protective breakwaters, used by fishing boats at Tarrafal on Santiago, Pedra de Lume on Sal and Ponta do Sol on Santo Antão.", "Some offer suitable protection for small yachts.", "The pier at Santa Maria on Sal used by both fishing and dive boats has been rehabilitated.", "'''Merchant marine:'''''total:'' 10''ships by type:'' chemical tanker 1, trawler/cargo ship 5, passenger/cargo 5''foreign owned:'' 2 (Spain 1, UK 1) (2008)'''Airports'''*7 operational in 2014 - 4 international and 3 domestic.", "*2 non-operational, one on Brava and the other on Santo Antão, closed for safety reasons.", "*Over 3,047 m: 1*1,524 to 2,437 m: 3*914 to 1,400 m: 3'''International Airports:'''* Amílcar Cabral International Airport, Sal Island.", "Opened and began operating international flights from 1939.Named Sal International Airport until 1975.", "* Nelson Mandela International Airport, Santiago Island.", "Opened and began operating international flights from 2005.Named Praia International Airport from 2005 until 2013.Replaced the Francisco Mendes International Airport which served the island from 1961 to 2005, and is now closed.", "* Aristides Pereira International Airport, Boa Vista Island.", "Airport paved and began operating international traffic in 2007.Named Rabil Airport until 2011.", "* Cesária Évora Airport, Sao Vicente Island.", "Opened in 1960 and became an international airport in 2009.Named Sao Pedro Airport until 2011.International passenger traffic is forecast to exceed 250,000 passengers for 2007.Annual growth, mostly of tourists from Europe is anticipated to continue at just under 20%.", "(Source ASA Cape Verde airport authority)'''Main Airlines serving the country:'''* '' TACV Cabo Verde Airlines''* '' Cabo Verde Express Cape Verde Express''* '' Halcyonair Cabo Verde Airways'' - dissolved in 2013* '' TAP Portugal''TACV flies daily international flights from Lisbon to Sal or Praia and once a week from Amsterdam, Munich, Paris, Las Palmas, Fortaleza and Boston to one or other of the international airports.", "It operates on a frequency varying from daily to thrice weekly on inter-island flights to each of the seven islands with operational airports and also to Dakar.", "It has a fleet of two Boeing 757s and three ATR42s have been replaced by ATR72s.", "It is currently (2010) undergoing privatization at the insistence of the World Bank." ], [ "Road network", "The road network of Cape Verde is managed by the national government (''Instituto de Estradas'') and by the municipalities.", "The total length of the road network is 1,650 km, of which 1,113 km national roads and 537 km municipal roads.", "Of the national roads, 36% is asphalted." ], [ "Air Services", "TACV Cabo Verde Airlines, the national airline, flies weekly from Boston Logan International Airport to Praia International Airport at Praia Santiago island.", "Currently (2007) these flights are on Wednesdays, but schedules vary and are subject to change.", "It also has flights four times weekly from Lisbon to Francisco Mendes (the recently opened airport at Praia on Santiago island) and four times weekly from Lisbon to Amílcar Cabral International Airport on Sal island.", "There is a flight on Mondays from Paris-Charles de Gaulle Airport to Sal and on Thursdays from Amsterdam Schiphol Airport via Munich-Riem Airport to Sal.", "Return flights are just after midnight on the same day.From Las Palmas in the Canary Islands, Spain there are night flights on Mondays and Thursdays, with departures just after midnight.", "Return flights are the previous day.", "There is a service from Praia to Fortaleza, Brazil on Mondays and Thursdays departing early evening and returning at night.", "All international flights are operated by Boeing 757 aircraft.", "Most international flights are subject to delay and sometimes cancellation.TAP Air Portugal the Portuguese national carrier operates a daily service from Lisbon to Sal with late evening departures returning after midnight and reaching Lisbon in the early morning.", "Most flights are delayed and onward connections from Lisbon can be missed as a result.", "TAP and other European carriers provide connections with most European capitals, enabling same day through flights.From the UK, direct routes by Astraeus from London Gatwick and Manchester to Sal ceased in April 2008; their website has not taken reservations since May 2008.TACV Cabo Verde Airlines opened a route from London Stansted in October 2008 though it was rumoured that flights were being cancelled due to minimum take up though with effect from May 2008, TACV have ceased flights from London Gatwick.", "There is a Fly TACV website, and you can book from their website.", "Reservations should be made via the UK TACV office on 0870 774 7338.Thomson Airways have opened additional routes from London Gatwick and Manchester on Mondays and Fridays.", "Various options and bookings can be made via Thomsonfly to both Sal and Boa Vista.Hamburg International provides a charter service from Hamburg via Düsseldorf on Thursdays and Condor operates from Frankfurt Rhein Main on Tuesdays returning on Wednesday.Neos operates charter flights from Milan Malpensa, Rome-Fiumicino and Bologna on Wednesdays.TACV Cabo Verde Airlines, the national airline has been a monopoly carrier within the island archipelago (2007).", "It operates services from the main hub airports at Sal and Santiago to Boa Vista, Fogo, Maio, São Nicolau and São Vicente at frequencies ranging from thrice weekly to thrice daily.", "Air strips on the other islands of Brava and Santo Antão are closed (2007) and can only be reached by ferry services from other islands.TACV does not publish timetables; flight times are listed on departure boards.", "Tickets can be bought at the TACV shop at each airport by queuing and paying in cash (euros or escudos).", "Flights are often delayed and sometimes cancelled due to weather or operational conditions.", "Services are operated by ATR 42 turboprop aircraft, which are being replaced (2007) by the enlarged ATR 72 aircraft.", "Inter island tariffs vary depending on the distance but are generally around €180 return.", "Air passes are obtainable for multiple flights, when buying an international ticket on TACV.Halcyonair a private carrier with Portuguese and Cape Verdean shareholders is commenced operations on inter-island flights during 2007.It has obtained the necessary licensing from the Cape Verde Government." ], [ "Travel within the islands", "Minibuses (''Aluguers'') on a beach in Baía das GatasA minibus (''aluguer'') on the island of BravaThe frequency and regularity of publicly-accessible ground transportation services vary between the islands and municipalities.", "There are some common features that can be found throughout Cape Verde.", "The primary mode of transportation between municipalities is via shared minibuses commonly referred to as a \"yasi\", because of the Toyota HiAce which makeup the majority of the minibuses in service.", "While 12-14 passenger \"yasi\" class minibuses connect the major municipalities at their end points, modified pickup trucks with partially covered cabs and benches installed in the back transport passengers along shorter distances through minor municipalities and the rural areas in between.", "These modified pickup trucks are referred to as \"hilux\" after the Toyota Hilux, the common model adapted.", "Notably, both \"yasi\" and \"hilux\" transportation will stop and pickup any passenger that hails them, as well as drop off any passenger that requests to disembark at any point.", "intermuncipality transportation licenses are granted on an individual basis to each vehicle in the name of the owner by the Direcção Geral dos Transportes e Rodoviários (General Directorate of Transport and Roads).", "With the exception of the Praia ⇄ Assomada route on Santiago, all yasi and hilux class vehicles licensed to carry passengers act as individual freelancers, not collectively.", "As such, they do not adhere to scheduling, and have no obligation to provide service.", "This includes many vehicles running the same route, owned by the same person.", "'''Brava'''Hiluxes and yasis connect Furna and Nova Sintra mostly when boats arrive.", "Other parts of the island are connected by these vehicles.", "'''Fogo'''Fogo has many yasis running the routes between São Filipe and Mosteiros, São Filipe and Chã das Calderas.", "Unlike many other islands, these buses depart at roughly the same time every day, and despite the presence of multiple vehicles running each route, passengers can find themselves stranded if they do not board a vehicle during the limited departure window.", "Yasis tend to depart Mosteiros headed to São Filipe around 6am, and tend to Depart São Filipe headed to Chã around noon.", "'''São Vicente'''Mindelo has a municipal bus service run by the company Transcor.", "Yasi and hilux transportation connects Mindelo with other parts of the island.", "Other transportation companies especially minibuses include Transporte Morabeza, Transporte Alegría, Amizade, Sotral y Automindelo.", "'''Santiago'''Maura Company and Sol Atlántico are the only two companies that have been granted municipal bus service licenses.", "Over the past decade, Maura Company, which had previously been the dominant bus company, has retired the majority of its buses, while many that continue to run are in a state of disrepair due to financial difficulties.", "Sol Atlántico, in contrast, has greatly increased its fleet of buses, adding several new high capacity buses in 2015.Municipal bus prices are regulated at 44 escudos per ride.", "Transfers are not allowed.", "Bus schedules do not exist, but buses start running around 6am and stop around 9pm.", "Bus stops exist, and are frequently infiltrated by minibus vehicles (also called \"yasis\") and both (taxi) licensed and unlicensed \"clan\" taxis illegally running municipal bus routes without a municipal license.", "No other city on Santiago has a municipal bus service.", "The government of Assomada has solicited requests for a bus service but so far none has been approved, and there are no short-term plans for any bus company to enter the municipal market.Transportation between the municipalities and rural areas is handled predominantly by yasi and hilux transportation.", "Rates are not fixed and range from 20 escudos for short trips between rural areas up to 500 escudos for Praia ⇄ Tarrafal.", "Some commonly accepted prices charged between municipalities are 100 escudos for Praia ⇄ São Domingos, 150 escudos for Praia ⇄ Orgãos, and 250 escudos for Praia ⇄ Assomada.", "Some of the yasis start collecting passengers before dawn to transport between Praia and Assomada and Praia and Pedra Badejo, and the last departures usually occur between 7 and 8pm.", "These vehicles do not maintain a schedule (with the exception of two early morning vehicles departing Assomada at 5:40 and 6:20 headed to Praia), instead choosing to drive around in circles within the urban centers of Praia, Assomada, and Pedra Badejo to pick up passengers until they are full, or over capacity (14 passengers is the legal limit for an actual Toyota HiAce), at which point they depart.", "Yasi drivers employ helpers to hawk out the window the destination of the yasi, as well as the obligatory \"cheio\", meaning full, with little regard for the number of people aboard.", "Helpers and drivers sometimes use shills (fake passengers) to overcome the common chicken and egg problem wherein passengers will not board an empty (or low passenger) minibus in an urban center because they know it will not depart until it is full.", "They will board a nearly-full (or over capacity) bus because they know it is likely to depart soon.", "In 2015 a project called EcobusCV started running a fleet of dual fuel waste vegetable oil / diesel modified Toyota HiACE minibuses using a scheduled service model between Praia and Assomada.", "Buses depart one per hour, on the hour, from designated bus stops in Praia, at Igreja Nova Apostólica in Fazenda, and Assomada, in front of the court house.", "The current departure schedule as of September 15 is one departure per hour, every hour starting at 7am, with the last departure at 6pm.", "EcobusCV plans to expand to departures in 30 minute intervals before the end of 2015.EcobusCV has instituted aggressive, transparent pricing undercutting the informal generally accepted prices between municipalities, which has started to cause freelance yasis to alter their pricing.Taxis are common in Praia and Assomada.", "Taxis with a base in Praia are painted beige, while taxis with a base in Assomada are painted white.", "They can carry passengers between municipalities, but they are prohibited from circulating and picking up passengers outside of their base city, though they will usually pickup passengers if they get hailed on their way back to their home city.", "Taximeters are installed in most legal taxis, but many are not functional and they are almost never used because the generally accepted rates are cheaper than what the taximeter would usually count.", "In Praia there is a large number of \"clan\" or clandestine taxis that operate without paying for a license.", "Most people identify Toyota Corolla hatchbacks as clans and they are frequently hailed.", "While the minimum taximeter price is officially 80, in practice 100 is the minimum a person pays if they board a taxi.", "Taxi rates in Praia generally go up to 250 escudos from the furthest points of the city to Plateau, and cross town taxis cap out at 400 during the day.", "Rates generally go up by 50 escudos after 10pm, though for longer distances some will try to charge an extra 100.An exception to this rule is the airport.", "Airport rates generally range from 500 to 1000 depending on the starting place or destination, and can go up by several hundred at night.", "'''Sal'''Sal has unscheduled yasi service between Espargos and Santa Maria, with frequent departures in the morning from Espargos, where most locals live, to Santa Maria, where most locals work, and vice versa in the afternoon." ], [ "Inter-Island ferries in Cape Verde", "Several ferries operate between the islands with much lower fares than the airlines.", "These are provided by various independent shipping companies and their conditions and seaworthiness vary.", "Many services depart from Praia at about midnight, arriving in outlying islands at breakfast time.", "Return trips often depart around mid-day.", "Service schedules are approximate and delays or cancellations of service are common.", "Conditions can be very crowded it is advisable to pre-book a cabin for all but the shortest of trips.", "Passages can be very rough in winter.Departure days vary according to the season and are frequently altered.", "Enquire at the shipping offices in Praia and other Cape Verdean ports.In early 2011, the Kriola, the first of a proposed fleet of ferryboats belonging to the company Cabo Verde Fast Ferry (CVFF) arrived in Praia directly from Singapore.", "It was custom-built there by the Dutch shipbuilding company, Damen Group.", "The Kriola operates regular service among the Sotavento islands of Brava, Fogo, and Santiago.===Ferry routes===*Boa Vista (Sal Rei)–Maio (Cidade do Maio)*Fogo (São Filipe-Vale de Cavaleiros)–Brava (Furna)*Maio (Cidade do Maio)–Santiago (Porto Praia)*Sal (Palmeira)–Boa Vista (Sal Rei)*Santiago (Porto Praia)–Fogo (São Filipe-Vale de Cavaleiros)*Santiago (Porto Praia)–São Vicente (Mindelo-Porto Grande) - longest ferry route*Santiago (Porto Praia)–Brava (Furna)*Santo Antāo (Porto Novo)–São Vicente (Mindelo-Porto Grande)*São Nicolau (Tarrafal de São Nicolau)–Sal (Palmeira)*São Nicolau (Preguiça)–Sal (Palmeira)*São Vicente (Porto Grande)–São Nicolau (Tarrafal de São Nicolau)*São Vicente (Porto Grande)–São Nicolau (Preguiça)'''Lesser ferry routes:'''**Within Santo Antão: Tarrafal de Monte Trigo–Monte Trigo (45 min) - shortest ferry route**Within Săo Nicolau: Preguiça–Carriçal" ], [ "References", "* Cape Verde Info UK 2007" ], [ "External links", "* Cape Verde Information Cape Verde Expatriate Residents Collaborative Pages* Cape Verde Information UK* Cape Verde Information - ''Cape Verde Transport Information''* Cape Verde Travel Information - ''Cape Verde Travel''" ] ]

[ [ "Cape Verdean Armed Forces" ], [ "Introduction", "The '''Cape Verdean Armed Forces''' (), '''Cabo Verdean Armed Forces''' or '''FACV''' are the military of Cape Verde.", "They include two branches, the National Guard and the Coast Guard." ], [ "History", "Cape Verdean MarinesBefore 1975, Cape Verde was an overseas province of Portugal, having a small Portuguese military garrison that included both Cape Verdean and European Portuguese soldiers.At the same time, some Cape Verdeans were serving in the People's Revolutionary Armed Forces (, FARP), the military wing of the African Party for the Independence of Guinea and Cape Verde that was fighting for the joint independence of Guinea and Cape Verde in the Guinea-Bissau War of Independence.", "The FARP became the national armed forces of Guinea-Bissau when its independence was recognized by Portugal in 1974.The Armed Forces of Cape Verde were created when the country became independent in 1975, being also officially designated the People's Revolutionary Armed Forces (, FARP).", "The Cape Verdean FARP consisted of two independent branches, the Army () and the Coast Guard ().In the early 1990s, the designation \"FARP\" was dropped and the military of Cape Verde was designated the Cape Verdean Armed Forces (, FACV).In 2007, the FACV started a major reorganization that included the transformation of the Army into the National Guard ().Together with the Cape Verdean Police, the FACV carried out Operation Flying Launch (), a successful operation to put an end to a drug trafficking group which smuggled cocaine from Colombia to the Netherlands and Germany using Cape Verde as a reorder point.", "The operation took more than three years, being a secret operation during the first two years, and ended in 2010.Although located in Africa, Cape Verde has always had close relations with Europe.", "Because of this, it has been argued that Cape Verde may be eligible for entry into the Organization for Security and Co-operation in Europe and NATO.The most recent engagement of the FACV was the Monte Tchota massacre that resulted in 11 deaths." ], [ "Structure", "The Cape Verdean Armed Forces are part of the Ministry of National Defense of Cape Verde and include:* the military bodies of command:** Chief of Staff of the Armed Forces** Office of the CEMFA** Staff of the Armed Forces (EMFA)** Personnel Command** Logistics Command* the National Guard* the Coast Guard===National Guard===Military Police in MindeloThe National Guard (''Guarda National'') is the main branch of the Cape Verdean Armed Forces for the military defense of the country, being responsible for the execution of land and maritime environment operations and the support to internal security.", "It includes:* Territorial commands:** 1st Military Region Command** 2nd Military Region Command** 3rd Military Region Command* Corps:** Military Police Corps** Marine Corps** Artillery CorpsThere is no general command of the National Guard.", "Each military region command is headed by a lieutenant-colonel directly subordinate to the Chief of Staff of the Armed Forces, and includes units of the three corps.===Coast Guard===Coast Guard patrol vessel ''Guardião'' (P511), in manoeuvres with a British frigateThe Coast Guard (''Guarda Costeira'') is the branch of the Cape Verdean Armed Forces responsible for the defense and protection of the country's economic interests at the sea under national jurisdiction and for providing air and naval support to land and amphibious operations.", "It includes:* Coast Guard Command* Maritime Security Operations Center (COSMAR)* Naval Squadron* Air SquadronThe Coast Guard is headed by an officer with the rank of lieutenant colonel.", "The Naval and Air Squadrons incorporate, respectively, all the vessels and aircraft of the Cape Verdean Armed Forces." ], [ "Ranks", "The rank insignia for commissioned officers for the national guard and coast guard.The rank insignia of enlisted for the national guard and coast guard." ], [ "Equipment", "=== Armored vehicles ===*10 BRDM-2===Artillery===*12 82-PM-41*6 120-PM-43 mortar===Anti-aircraft===* 9K32 Strela-2*18 ZPU-1*12 ZU-23-2=== Aircraft ===Dornier 228 of the Cape Verdean Coast GuardPatrol boat ''Tainha'' (P 262)The Cape Verdean Army used to have its own air arm; after personnel training received from the USSR in 1982, three Antonov An-26 aircraft were delivered to Cape Verde – these were believed to be the only military aircraft possessed by the nation.", "However these three aircraft were supplemented in 1991 by a Dornier 228 light aircraft equipped for use by the Coast Guard, and, in the late 1990s by an EMB-110 aircraft from Brazil, similarly equipped for maritime operations.", "The government has been in negotiations with China to acquire multirole helicopters for both military and civilian use.====Current Inventory====AircraftOriginTypeVariantIn serviceNotes Maritime patrol CASA C-212 Spain SAR/Maritime patrol 1 Flown for the Coast Guard Dornier 228 Germany SAR/Maritime patrol 2 Flown for the Coast Guard HelicoptersHarbin Z-9ChinaSAR/Utility 2 Flown for the Coast Guard=== Vessels ===* 1 Kondor I patrol craft – 360 tons full load – commissioned 1970* 1 Peterson MK 4 patrol craft – 22 tons – commissioned 1993* 1 other patrol craft – 55 tons* 1 Damen Stan 5009 patrol vessel – ''Guardiao (P511)'' – commissioned 2012" ], [ "References", "*Further reading: Defense Intelligence Agency, Military Intelligence Summary - Africa South of the Sahara, DDB 2680-104-85, ICOD 15 October 1984, declassified by letter dated April 29, 2014." ], [ "External links", "* The World Factbook* http://www.nationmaster.com/country/cv-cape-verde/mil-military* https://web.archive.org/web/20110721071532/http://praia.usembassy.gov/about-us/security-assistance-office.html* http://www.snpc.cv/ * Cape Verde Military Police" ] ]

[ [ "Foreign relations of Cape Verde" ], [ "Introduction", "Cape Verde follows a policy of nonalignment and seeks cooperative relations with all friendly states.", "Angola, Brazil, the People's Republic of China, Cuba, France, Germany, Portugal, Senegal, Russia, South Korea and the United States maintain embassies in Praia.Cape Verde is actively interested in foreign affairs, especially in Africa.", "It has bilateral relations with some Lusophone nations and holds membership in a number of international organizations.", "It also participates in most international conferences on economic and political issues." ], [ "Diplomatic relations", "List of countries which Cape Verde maintains diplomatic relations with:425x425px#CountryDate1234567891011121314151617181920212223—242526272829303132333435363738394041424344Before March 197845Before March 19784647484950515253545556575859606162636465666768697071727374757677787980818283—8485868788899091929394959697989910010114 March 2007102103104105—106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144Unknown}" ], [ "Bilateral relations", " Country Formal Relations BeganNotesSee Angola–Cape Verde relationsCape Verde signed a friendship accord with Angola in December 1975, shortly after Angola gained its independence.", "Cape Verde and Guinea-Bissau served as stop-over points for Cuban troops on their way to Angola to fight UNITA rebels and South African troops.", "Prime Minister Pedro Pires sent FARP soldiers to Angola where they served as the personal bodyguards of Angolan President José Eduardo dos Santos.", "* Angola has an embassy in Praia.", "* Cape Verde has an embassy in Luanda and a consulate in Benguela.See Brazil–Cape Verde relations* Cape Verde has an embassy in Brasília.", "* Brazil has an embassy in Praia.See Cape Verde–China relationsIn January 2007, Manuel Inocêncio Sousa, Minister of Infrastructure, Transports and Sea, acknowledged the People's Republic of China's importance to Cape Verde stating:\"''China has been a friend of Cape Verde even before it gained independence from Portugal 30 years ago.", "Bilateral relations have been very good: in 2002, for example, the trade value between our two countries reached US $1.8 million, in Chinese exports of light industry products and miscellaneous goods.", "''\"* Cape Verde has an embassy in Beijing.", "* China has an embassy in Praia.28 October 1975 and 1 January 1993* Cape Verde is accredited to the Czech Republic from its embassy in Berlin, Germany.", "* Czech Republic is accredited to Cape Verde by its embassy in Lisbon, Portugal and an honorary consulate in Praia.", "See Cape Verde–France relations* Cape Verde has an embassy in Paris and a consulate-general in Nice.", "* France has an embassy in Praia.5 July 1975 See Cape Verde–Guinea-Bissau relationsThe Republic of Guinea-Bissau is about 900 km south-east of Cape Verde in coastal West Africa.", "Both were colonies of the Portuguese Empire and they campaigned together for independence with a plan for unification, but the countries separated after 1980.", "* Cape Verde has an embassy in Bissau.", "* Guinea-Bissau has an embassy in Praia.Both countries established diplomatic relations on 16 July 1975Hungary is represented in Cape-Verde by its embassy in Lisbon, Portugal and an honorary consulate in Praia.See Cape Verde–India relationsAfter Cape Verde became a Portuguese colony in the 15th century, it became an important transit point for trade routes from Europe to India and Australia.", "The Embassy of India in Dakar, Senegal is concurrently accredited to Cape Verde.", "Cape Verde maintains an Honorary Consulate General in New Delhi.Foreign Minister Jose Brito was the first Cape Verdean minister to visit India in November 2009.Minister of State for Rural Development Sudarshan Bhagat visited Cape Verde in September 2015 as the Prime Minister's Special Envoy.", "Bhagat invited Cape Verde to send a delegation to attend the third India Africa Forum Summit.", "Foreign Minister Tolentini Araujo Jorge led the Cape Verdean delegation to participate in the Summit in New Delhi in October 2015.Bilateral trade between Cape Verde and India totaled US$4.20 million in 2014 to 2015, declining by 40.72% from the previous fiscal.", "India exported $1.43 million worth of goods to Cape Verde, and imported $2.77 million.", "The main commodities exported from India to Cape Verde are drugs, pharmaceuticals, plastic and linoleum products, and man-made fibers.IBSA provided a grant to refurbish a healthcare Centre in Cape Verde.", "India provided a line of credit worth $5 million to establish a Technology Park in the country.", "India donated $50,000 in 2010 to help the Government of Cape Verde to fight dengue fever, and supplied computers for the Government's \"A New World\" programme in October 2012.Citizens of Cape Verde are eligible for scholarships under the Indian Technical and Economic Cooperation Programme and the Indian Council for Cultural Relations.A small Indian community resides in Cape Verde.Indonesia is represented in Cape Verde by its embassy in Dakar.19 February 1976Both countries established diplomatic relations on 19 February 1976* Cape Verde is accredited to Mexico from its embassy in Washington, D.C., United States.", "* Mexico is accredited to Cape Verde from its Permanent Mission to the United Nations in New York City.15 March 1976* Cape Verde is accredited to Mozambique from its embassy in Luanda, Angola and maintains an honorary consulate in Maputo.", "* Mozambique is accredited to Cape Verde from its Ministry of Foreign Affairs in Maputo.", "* Both nations also conduct diplomatic relations from their respective ambassadors accredited to the CPLP in Lisbon, Portugal.See Cape Verde–Portugal relationsBoth countries established diplomatic relations on 6 July 1975 when Chargé d'Affaires of Portugal Embassy in Praia Manuel António Pacheco Jorge Barreiros presented letters of credentials* Cape Verde has an embassy in Lisbon.", "* Portugal has an embassy in Praia.Both countries established diplomatic relations on 14 July 1975* Cape Verde has an honorary consulate in Moscow.", "* Russia has an embassy in Praia.Both countries established diplomatic relations on 4 April 1994* Cape Verde is accredited to South Africa from its embassy in Luanda, Angola.", "* South Africa is accredited to Cape Verde from its embassy in Dakar, Senegal.Both countries established diplomatic relations on 3 October 1988 In 2011 Bilateral Trade were Exports $1,140,792 (Machineries, Automobile, Optical Instruments) Imports: $65,166.See Cape Verde–Spain relations* Cape Verde has an embassy in Madrid.", "* Spain has an embassy in Praia.See Cape Verde–Turkey relations*The Turkish embassy in Dakar, Senegal is accredited to Cape Verde.", "*Trade volume between the two countries was $9.5 million in 2019.Both countries established diplomatic relations on 25 March 1992Ukraine is represented in Cape-Verde by its embassy in Dakar, Senegal.See Cape Verde–United States relationsThe United States provided emergency humanitarian aid and economic assistance to Cape Verde in the period immediately following Cape Verde's independence, as well as after natural disasters, including a hurricane that struck the island of Brava in 1982, and after a severe volcanic eruption on Fogo in 1995.Cape Verde also is eligible for trade benefits under the African Growth and Opportunity Act (AGOA), and has signed an Open Skies agreement to facilitate air travel safety and expansion.", "On July 4, 2005, Cape Verde became the third country to sign a compact with the U.S. Government-funded Millennium Challenge Corporation (MCC); the five-year assistance package is worth over $110 million in addressing rural economic expansion, infrastructure development, and development of the credit sector.", "* Cape Verde has an embassy in Washington, D.C., and a consulate in Boston.", "* United States has an embassy in Praia." ], [ "Multilateral Relations", "===European Union===" ], [ "See also", "* List of diplomatic missions in Cape Verde* List of diplomatic missions of Cape Verde* International organization membership of Cape Verde* International recognition of Cape Verde" ], [ "References" ] ]

[ [ "Cayman Islands" ], [ "Introduction", "The '''Cayman''' '''Islands''' () is a self-governing British Overseas Territory, and the largest by population.", "The territory comprises the three islands of Grand Cayman, Cayman Brac and Little Cayman, which are located south of Cuba and north-east of Honduras, between Jamaica and Mexico's Yucatán Peninsula.", "The capital city is George Town on Grand Cayman, which is the most populous of the three islands.The Cayman Islands is considered to be part of the geographic Western Caribbean zone as well as the Greater Antilles.", "The territory is a major offshore financial centre for international businesses and wealthy individuals, largely as a result of the state not charging taxes on any income earned or stored.With a GDP per capita of $91,392, the Cayman Islands has the highest standard of living in the Caribbean, and one of the highest in the world.", "Immigrants from over 140 countries and territories reside in the Cayman Islands." ], [ "History", "2 dollar Cayman 1975It is likely that the Cayman Islands were first visited by the Amerindians, the Indigenous peoples of the Caribbean.", "The Cayman Islands got their name from the word for crocodile (''caiman'') in the language of the Arawak-Taíno people.", "It is believed that the first European to sight the islands was Christopher Columbus, on 10 May 1503, during his final voyage to the Americas.", "He named them \"Las Tortugas\", after the large number of turtles found there (which were soon hunted to near-extinction).However, in succeeding decades, the islands began to be referred to as \"Caimanas\" or \"Caymanes\", after the caimans present there.", "No immediate colonisation followed Columbus's sighting, but a variety of settlers from various backgrounds eventually arrived, including pirates, shipwrecked sailors, and deserters from Oliver Cromwell's army in Jamaica.", "Sir Francis Drake briefly visited the islands in 1586.Cayman Islands National Museum, George Town, Grand CaymanThe first recorded permanent inhabitant, Isaac Bodden, was born on Grand Cayman around 1661.He was the grandson of an original settler named Bodden, probably one of Oliver Cromwell's soldiers involved in the capture of Jamaica from Spain in 1655.England took formal control of the Cayman Islands, along with Jamaica, as a result of the Treaty of Madrid of 1670.That same year saw an attack on a turtle fishing settlement on Little Cayman by the Spanish under Manuel Ribeiro Pardal.", "Following several unsuccessful attempts at settlement in what had by then become a haven for pirates, a permanent English-speaking population in the islands dates from the 1730s.", "With settlement, after the first royal land grant by the governor of Jamaica in 1734, came the introduction of slaves.", "Many were purchased and brought to the islands from Africa.", "That has resulted in the majority of native Caymanians being of African or English descent.", "The first census taken in the islands, in 1802, showed the population on Grand Cayman to be 933, with 545 of those inhabitants being slaves.", "Slavery was abolished in the Cayman Islands in 1833, following the passing of the Slavery Abolition Act by the British Parliament.", "At the time of abolition, there were over 950 slaves of African ancestry, owned by 116 families.On 22 June 1863, the Cayman Islands was officially declared and administered as a dependency of the Crown Colony of Jamaica.", "The islands continued to be governed as part of the Colony of Jamaica until 1962, when they became a separate Crown colony, after Jamaica became an independent Commonwealth realm.The Heroes Square in the centre of George Town, which commemorates the Cayman Islands' war dead.", "The Legislative Assembly building is at the left.On 8 February 1794, the Caymanians rescued the crews of a group of ten merchant ships, including HMS ''Convert'', an incident that has since become known as the Wreck of the Ten Sail.", "The ships had struck a reef and run aground during rough seas.", "Legend has it that King George III rewarded the islanders for their generosity with a promise never to introduce taxes, because one of the ships carried a member of the King's family.", "Despite the legend, the story is not true.In the 1950s, tourism began to flourish, following the opening of Owen Roberts International Airport (ORIA), along with a bank and several hotels, as well as the introduction of a number of scheduled flights and cruise stop-overs.", "Politically, the Cayman Islands were an internally self-governing territory of Jamaica from 1958 to 1962, but they reverted to direct British rule following the independence of Jamaica in 1962.In 1972, a large degree of internal autonomy was granted by a new constitution, with further revisions being made in 1994.The Cayman Islands government focused on boosting the territory's economy via tourism and the attraction of off-shore finance, both of which mushroomed from the 1970s onwards.", "Historically, the Cayman Islands has been a tax-exempt destination, and the government has always relied on indirect and not direct taxes.", "The territory has never levied income tax, capital gains tax, or any wealth tax, making it a popular tax haven.In April 1986, the first marine protected areas were designated in the Cayman Islands, making them the first islands in the Caribbean to protect their fragile marine life.The constitution was further modified in 2001 and 2009, codifying various aspects of human rights legislation.On 11 September 2004, the island of Grand Cayman, which lies largely unprotected at sea level, was battered by Hurricane Ivan, the worst hurricane to hit the islands in 86 years.", "It created an storm surge which flooded many areas of Grand Cayman.", "An estimated 83% of the dwellings on the island were damaged, with 4% requiring complete reconstruction.", "A reported 70% of all dwellings suffered severe damage from flooding or wind.", "Another 26% sustained minor damage from partial roof removal, low levels of flooding, or impact with floating or wind-driven hurricane debris.", "Power, water and communications were disrupted for months in some areas.", "Within two years, a major rebuilding program on Grand Cayman meant that its infrastructure was almost back to its pre-hurricane condition.", "Due to the tropical location of the islands, more hurricanes or tropical systems have affected the Cayman Islands than any other region in the Atlantic basin.", "On average, it has been brushed, or directly hit, every 2.23 years." ], [ "Geography", "Map of the Cayman Islands, showing the three main islands about apartThe islands are in the western Caribbean Sea and are the peaks of an undersea mountain range called the Cayman Ridge (or Cayman Rise).", "This ridge flanks the Cayman Trough, deep which lies to the south.", "The islands lie in the northwest of the Caribbean Sea, east of Quintana Roo, Mexico and Yucatán State, Mexico, northeast of Costa Rica, north of Panama, south of Cuba and west of Jamaica.", "They are situated about south of Miami, east of Mexico, south of Cuba, and about northwest of Jamaica.", "Grand Cayman is by far the largest, with an area of .", "Grand Cayman's two \"sister islands\", Cayman Brac and Little Cayman, are about east north-east of Grand Cayman and have areas of respectively.", "The nearest land mass from Grand Cayman is the Canarreos Archipelago (about 240 km or 150 miles away), whereas the nearest from the easternmost island Cayman Brac is the Jardines de la Reina archipelago (about 160 km or 100 miles away) – both of which are part of Cuba.George Town waterfront.All three islands were formed by large coral heads covering submerged ice-age peaks of western extensions of the Cuban Sierra Maestra range and are mostly flat.", "One notable exception to this is The Bluff on Cayman Brac's eastern part, which rises to above sea level, the highest point on the islands.The terrain is mostly a low-lying limestone base surrounded by coral reefs.", "The portions of prehistoric coral reef that line the coastline and protrude from the water are referred to as ''ironshore''.===Fauna===Blue iguanaThe mammalian species in the Cayman Islands include the introduced Central American agouti and eight species of bats.", "At least three now extinct native rodent species were present until the discovery of the islands by Europeans.", "Marine life around the island of the Grand Cayman includes tarpon, silversides (''Atheriniformes''), French angelfish (''Pomacanthus paru''), and giant barrel sponges.", "A number of cetaceans are found in offshore waters.", "These species include the goose-beaked whale (''Ziphius cavirostris''), Blainville's beaked whale (''Mesoplodon densirostris'') and sperm whale (''Physeter macrocephalus'').Cayman avian fauna includes two endemic subspecies of ''Amazona'' parrots: ''Amazona leucocephala hesterna'' or Cuban amazon, presently restricted to the island of Cayman Brac, but formerly also on Little Cayman, and ''Amazona leucocephala caymanensis'' or Grand Cayman parrot, which is native to the Cayman Islands, forested areas of Cuba, and the Isla de la Juventud.", "Little Cayman and Cayman Brac are also home to red-footed and brown boobies.", "Although the barn owl (''Tyto alba'') occurs in all three of the islands they are not commonplace.", "The Cayman Islands also possess five endemic subspecies of butterflies.", "These butterfly breeds can be viewed at the Queen Elizabeth II Botanic Park on the Grand Cayman.Among other notable fauna at the Queen Elizabeth II Botanic Park is the critically threatened blue iguana which is also known as the Grand Cayman iguana (''Cyclura lewisi'').", "The blue iguana is endemic to the Grand Cayman particularly because of rocky, sunlit, open areas near the island's shores that are advantageous for the laying of eggs.", "Nevertheless, habitat destruction and invasive mammalian predators remain the primary reasons that blue iguana hatchlings do not survive naturally.The Cuban crocodile (''Crocodylus rhombifer'') once inhabited the islands.", "The name \"Cayman\" is derived from a Carib word for various crocodilians.Signs at Rum Point commemorating landed and near-miss hurricanes===Climate===The Cayman Islands has a tropical wet and dry climate, with a wet season from May to October, and a dry season that runs from November to April.", "Seasonally, there is little temperature change.A major natural hazard is the tropical cyclones that form during the Atlantic hurricane season from June to November.On 11 and 12 September 2004, Hurricane Ivan struck the Cayman Islands.", "The storm resulted in two deaths and caused significant damage to the infrastructure on the islands.", "The total economic impact of the storms was estimated to be $3.4 billion." ], [ "Demographics", "===Demographics & immigration===While there are a large number of generational Caymanians, many Caymanians today have roots in almost every part of the world.", "Similarly to countries like the United States, the Cayman Islands is a melting pot with citizens of every background.", "52.5% of the population is Non-Caymanian, while 47.5% is Caymanian.According to the Economics and Statistics Office of the Government of the Cayman Islands, the Cayman Islands had a population of 71,432 at the Census of 10 October 2021, but was estimated by them to have risen to 81,546 as of December 2022, making it the most populous British Overseas Territory.", "It was revealed in the 2021 census that 56% of the workforce is Non-Caymanian; this is the first time in the territory's history that the number of working immigrants has overtaken the number of working Caymanians.", "Most Caymanians are of mixed African and European ancestry.", "Slavery was not common throughout the islands, and once it was abolished, black and white communities seemed to integrate more compliantly than other Caribbean nations and territories, resulting in a more mixed-race population.The country's demographics are changing rapidly.", "Immigration plays a large role, and the changing demographics in age have sounded alarm bells in the most recent census.", "In comparison to the 2010 census, the 2021 census has shown that 36% of Cayman's population growth has been in persons over age 65, while 8% growth was recorded in groups under age 15.This is due to extremely low birth rates among Caymanians, which almost forces the government to seek workers from overseas to sustain the country's economy.", "This has raised concerns among many young Caymanians, who worry about the workforce becoming increasingly competitive with the influx of workers, as well as rent and property prices going up.Because the population has skyrocketed over the last decade, the Premier of the Cayman Islands, Wayne Panton, has stressed that the islands need more careful and managed growth.", "Many have worried that the country's infrastructure and services cannot cope with the surging population.", "It is believed that given current trends, the population will reach 100,000 before 2030.===District populations===Traditional Caymanian home in East End, Grand CaymanAccording to the Economics and Statistics Office, the final result of the 20 October 2021 Census was 71,432; however, according to a late 2022 population report by the same body, the estimated population at the end of 2022 was 81,546, broken down as follows: Name ofdistrict Area in sq.km PopulationCensus2010 PopulationCensus2021 Populationestimatelate 2022 West Bay 17.411,22215,33516,943 George Town 38.528,08934,92140,957 Bodden Town 50.510,54314,84516,957 North Side 39.41,4791,9022,110 East End 51.11,4071,8462,274 Total Grand Cayman197.053,16069,17579,242 Little Cayman 26.0197182 Cayman Brac 36.02,0992,0752,304 Total Cayman Islands259.055,45671,43281,546 ===Religion===The predominant religion on the Cayman Islands is Christianity (66.9%, down from over 80% in 2010).", "Religions practised include United Church, Church of God, Anglican Church, Baptist Church, Catholic Church, Seventh-day Adventist Church, and Pentecostal Church.", "Roman Catholic churches are St. Ignatius Church, George Town, Christ the Redeemer Church, West Bay and Stella Maris Church, Cayman Brac.", "Many citizens are deeply religious, regularly going to church, however, atheism has been on the rise throughout the islands since 2000, with 16.7% now identifying with no religion, according to the 2021 census.", "Ports are closed on Sundays and Christian holidays.", "There is also an active synagogue and Jewish community on the island as well as places of worship in George Town for Jehovah's Witnesses and followers of the Bahá'í faith.In 2020, there were an estimated 121 Muslims in the Cayman Islands.Elmslie United Church, George Town===Languages===The official language of the Cayman Islands is English (90%).", "Islanders' accents retain elements passed down from English, Scottish, and Welsh settlers (among others) in a language variety known as Cayman Creole.", "Caymanians of Jamaican origin speak in their own vernacular (see Jamaican Creole and Jamaican English).", "It is quite common to hear residents converse in Spanish as many citizens have relocated from Latin America to work and live on Grand Cayman.", "The Latin American nations with the greatest representation are Honduras, Cuba, Colombia, Nicaragua, and the Dominican Republic.", "Spanish speakers comprise approximately between 10 and 12% of the population and are predominantly of the Caribbean dialect.", "Tagalog is spoken by about 8% of inhabitants, most of whom are Filipino residents on work permits." ], [ "Economy", "According to ''Forbes'', the Cayman Islands has the 7th strongest currency in the world (the CI dollar or KYD), with US$1.00 equivalent to CI$0.80.The economy of the Cayman Islands is dominated by financial services and tourism, together accounting for 50–60% of Gross Domestic Product.", "The nation's low tax rates have led to it being used as a tax haven for corporations; there are 100,000 companies registered in the Cayman Islands, more than the population itself.", "The Cayman Islands have come under criticism for allegations of money laundering and other financial crimes, including a 2016 statement by then US president Barack Obama that described a particular building which was the registered address of over 12,000 corporations as a \"tax scam\".The Cayman Islands holds a relatively low unemployment rate of about 4.24% as of 2015, lower than the value of 4.7% that was recorded in 2014.With an average income of US$71,549, Caymanians have the highest standard of living in the Caribbean.", "According to the CIA ''World Factbook'', the Cayman Islands' real GDP per capita is the tenth highest in the world, but the CIA's data for Cayman dates to 2018 and is likely to be lower than present-day values.", "The territory prints its own currency, the Cayman Islands dollar (KYD), which is pegged to the US dollar US$1.227 to 1 KYD.", "However, in many retail stores throughout the islands, the KYD is typically traded at US$1.25.Cayman Islands have a high cost of living, even when compared to UK and US.", "For example, a loaf of multigrain bread is $5.49 (KYD), while a similar loaf sells for $2.47 (KYD) in the US and $1.36 (KYD) in the UK.The minimum wage (as of February 2021) is $6 KYD for standard positions, and $4.50 for workers in the service industry, where tips supplement income.", "This contributes to wealth disparity.", "A small segment of the population lives in condemned properties lacking power and running water.The government has established a Needs Assessment Unit to relieve poverty in the islands.", "Local charities, including Cayman's Acts of Random Kindness (ARK) also provide assistance.The government's primary source of income is indirect taxation: there is no income tax, capital gains tax, or corporation tax.", "An import duty of 5% to 22% (automobiles 29.5% to 100%) is levied against goods imported into the islands.", "Few goods are exempt; notable exemptions include books, cameras, and perfume.===Tourism===One of Grand Cayman's main attractions is Seven Mile Beach, site of a number of the island's hotels and resorts.", "Named one of the Ultimate Beaches by Caribbean Travel and Life, Seven Mile Beach (due to erosion over the years, the number has decreased to 5.5 miles) is a public beach on the western shore of Grand Cayman Island.", "Historical sites in Grand Cayman, such as Pedro St. James Castle in Savannah, also attract visitors.", "302x302pxStingray passing through Stingray City, Grand CaymanAll three islands offer scuba diving, and the Cayman Islands are home to several snorkelling locations where tourists can swim with stingrays.", "The most popular area to do this is Stingray City, Grand Cayman.", "Stingray City is a top attraction in Grand Cayman and originally started in the 1980s when divers started feeding squid to stingrays.", "The stingrays started to associate the sound of the boat motors with food, and thus visit this area year-round.There are two shipwrecks off the shores of Cayman Brac, including the MV Captain Keith Tibbetts; Grand Cayman also has several shipwrecks off its shores, including one deliberate one.", "On 30 September 1994, the was decommissioned and struck from the Naval Vessel Register.", "In November 2008 her ownership was transferred for an undisclosed amount to the government of the Cayman Islands, which had decided to sink the ''Kittiwake'' in June 2009 to form a new artificial reef off Seven Mile Beach, Grand Cayman.", "Following several delays, the ship was finally scuttled according to plan on 5 January 2011.The ''Kittiwake'' has become a dynamic environment for marine life.", "While visitors are not allowed to take anything, there are endless sights.", "Each of the five decks of the ship offers squirrelfish, rare sponges, Goliath groupers, urchins, and more.", "Experienced and beginner divers are invited to swim around the ''Kittiwake''.", "Pirates Week is an annual 11-day November festival started in 1977 by the then-Minister of Tourism Jim Bodden to boost tourism during the country's tourism slow season.Other Grand Cayman tourist attractions include the ironshore landscape of Hell; the marine theme park \"Cayman Turtle Centre: Island Wildlife Encounter\", previously known as \"Boatswain's Beach\"; the production of gourmet sea salt; and the Mastic Trail, a hiking trail through the forests in the centre of the island.", "The National Trust for the Cayman Islands provides guided tours weekly on the Mastic Trail and other locations.Another attraction to visit on Grand Cayman is the Observation Tower, located in Camana Bay.", "The Observation Tower is 75 feet tall and provides 360-degree views across Seven Mile Beach, George Town, the North Sound, and beyond.", "It is free to the public and climbing the tower has become a popular thing to do in the Cayman Islands.Points of interest include the East End Light (sometimes called Gorling Bluff Light), a lighthouse at the east end of Grand Cayman island.", "The lighthouse is the centrepiece of East End Lighthouse Park, managed by the National Trust for the Cayman Islands; the first navigational aid on the site was the first lighthouse in the Cayman Islands.===Shipping===, 360 commercial vessels and 1,674 pleasure craft were registered in the Cayman Islands totalling 4.3 million GT.===Labour===The Cayman Islands has a population of 69,656 () and therefore a limited workforce.", "Work permits may, therefore, be granted to foreigners.", "On average, there have been more than 24,000+ foreigners holding valid work permits.====Work permits for non-citizens====To work in the Cayman Islands as a non-citizen, a work permit is required.", "This involves passing a police background check and a health check.", "A prospective immigrant worker will not be granted a permit unless certain medical conditions are met, including testing negative for syphilis and HIV.", "A permit may be granted to individuals on special work.A foreigner must first have a job to move to the Cayman Islands.", "The employer applies and pays for the work permit.", "Work permits are not granted to foreigners who are in the Cayman Islands (unless it is a renewal).", "The Cayman Islands Immigration Department requires foreigners to remain out of the country until their work permit has been approved.The Cayman Islands presently imposes a controversial \"rollover\" in relation to expatriate workers who require a work permit.", "Non-Caymanians are only permitted to reside and work within the territory for a maximum of nine years unless they satisfy the criteria of key employees.", "Non-Caymanians who are \"rolled over\" may return to work for additional nine-year periods, subject to a one-year gap between their periods of work.", "The policy has been the subject of some controversy within the press.", "Law firms have been particularly upset by the recruitment difficulties that it has caused.", "Other less well-remunerated employment sectors have been affected as well.", "Concerns about safety have been expressed by diving instructors, and realtors have also expressed concerns.", "Others support the rollover as necessary to protect Caymanian identity in the face of immigration of large numbers of expatriate workers.Concerns have been expressed that in the long term, the policy may damage the preeminence of the Cayman Islands as an offshore financial centre by making it difficult to recruit and retain experienced staff from onshore financial centres.", "Government employees are no longer exempt from this \"rollover\" policy, according to this report in a local newspaper.", "The governor has used his constitutional powers, which give him absolute control over the disposition of civil service employees, to determine which expatriate civil servants are dismissed after seven years service and which are not.This policy is incorporated in the Immigration Law (2003 revision), written by the United Democratic Party government, and subsequently enforced by the People's Progressive Movement Party government.", "Both governments agree to the term limits on foreign workers, and the majority of Caymanians also agree it is necessary to protect local culture and heritage from being eroded by a large number of foreigners gaining residency and citizenship.====CARICOM Single Market Economy====In recognition of the CARICOM (Free Movement) Skilled Persons Act which came into effect in July 1997 in some of the CARICOM countries such as Jamaica and which has been adopted in other CARICOM countries, such as Trinidad and Tobago it is possible that CARICOM nationals who hold the \"A Certificate of Recognition of Caribbean Community Skilled Person\" will be allowed to work in the Cayman Islands under normal working conditions." ], [ "Government", " The Cayman Islands are a British overseas territory, listed by the UN Special Committee of 24 as one of the 16 non-self-governing territories.", "The current Constitution, incorporating a Bill of Rights, was ordained by a statutory instrument of the United Kingdom in 2009.A 19-seat (not including two non-voting members appointed by the Governor which brings the total to 21 members) Parliament is elected by the people every four years to handle domestic affairs.", "Of the elected Members of the Parliament (MPs), seven are chosen to serve as government Ministers in a Cabinet headed by the Governor.", "The Premier is appointed by the Governor.A Governor is appointed by the King of the United Kingdom on the advice of the British Government to represent the monarch.", "Governors can exercise complete legislative and executive authority if they wish through blanket powers reserved to them in the constitution.", "Bills which have passed the Parliament require royal assent before becoming effective.", "The Constitution empowers the Governor to withhold royal assent in cases where the legislation appears to be repugnant to or inconsistent with the Constitution or affects the rights and privileges of the Parliament or the Royal Prerogative, or matters reserved to the Governor by article 55.The executive authority of the Cayman Islands is vested in the King and is exercised by the Government, consisting of the Governor and the Cabinet.", "There is an office of the Deputy Governor, who must be a Caymanian and have served in a senior public office.", "The Deputy Governor is the acting Governor when the office of Governor is vacant, or the Governor is not able to discharge their duties or is absent from the Cayman Islands.", "The current Governor of the Cayman Islands is Jane Owen.The Cabinet is composed of two official members and seven elected members, called Ministers; one of whom is designated Premier.", "The premier can serve for two consecutive terms.", "After two terms the premier is barred from attaining the office again.", "Although an MP can only be premier twice any person who meets the qualifications and requirements for a seat in the Parliament can be elected to the Parliament indefinitely.There are two official members of the Parliament, the Deputy Governor and the Attorney General.", "They are appointed by the Governor in accordance with His Majesty's instructions, and although they have seats in the Parliament, under the 2009 Constitution, they do not vote.", "They serve in a professional and advisory role to the MPs, the Deputy Governor represents the Governor who is a representative of the King and the British Government.", "While the Attorney General serves to advise on legal matters and has special responsibilities in Parliament, they are generally responsible for changes to the Penal code.The seven Ministers are voted into office by the 19 elected members of the Parliament of the Cayman Islands.", "One of the Ministers, the leader of the majority political party, is appointed Premier by the Governor.After consulting the Premier, the Governor allocates a portfolio of responsibilities to each Cabinet Minister.", "Under the principle of collective responsibility, all Ministers are obliged to support in the Parliament any measures approved by Cabinet.Almost 80 departments, sections and units carry out the business of government, joined by a number of statutory boards and authorities set up for specific purposes, such as the Port Authority, the Civil Aviation Authority, the Immigration Board, the Water Authority, the University College Board of Governors, the National Pensions Board and the Health Insurance Commission.Since 2000, there have been two official major political parties: The Cayman Democratic Party (CDP) and the People's Progressive Movement (PPM).", "While there has been a shift to political parties, many contending for office still run as independents.", "The two parties are notably similar, though they consider each other rivals in most cases, their differences are generally in personality and implementation rather than actual policy.", "The Cayman Islands generally lacks any form of organised political parties.", "As of the May 2017 General Election, members of the PPM and CDP have joined with three independent members to form a government coalition despite many years of enmity.===Police===Policing in the country is provided chiefly by the RCIPS or Royal Cayman Islands Police Service and the CICBC or Cayman Islands Customs & Border Control.", "These two agencies co-operate in aspects of law enforcement, including their joint marine unit.===Military and defence===The defence of the Cayman Islands is the responsibility of the United Kingdom.", "The Royal Navy maintains a ship on permanent station in the Caribbean (HMS Medway (P223)) and, from time-to-time, the Royal Navy or Royal Fleet Auxiliary may deploy another ship as a part of Atlantic Patrol (NORTH) tasking.", "These ships' main mission in the region is to maintain British sovereignty for the overseas territories, provide humanitarian aid and disaster relief during disasters such as hurricanes, which are common in the area, and to conduct counter-narcotic operations.====Cayman Islands Regiment====On 12 October 2019, the government announced the formation of the Cayman Islands Regiment, a new British Armed Forces unit.", "The Cayman Islands Regiment which became fully operational in 2020, with an initial 35–50 personnel of mostly reservists.", "Between 2020 through 2021 the Regiment grew to over a hundred personnel and over the next several years expected to grow to over several hundred personnel.In mid-December 2019, recruitment for commanding officers and junior officers began, with the commanding officers expected to begin work in January 2020 and the junior officers expected to begin in February 2020.In January 2020, the first officers were chosen for the Cayman Islands Regiment.Since the formation of the Regiment, it has been deployed on a few operational tours providing HADR or Humanitarian Aid and Disaster Relief as well as assisting with the COVID19 Pandemic.====Cadet Corps====The Cayman Islands Cadet Corps was formed in March 2001 and carries out military-type training with teenage citizens of the country.====Coast Guard====In 2018, the PPM-led Coalition government pledged to form a coast guard to protect the interests of the Cayman Islands, especially in terms of illegal immigration and illegal drug importation as well as search and rescue.", "In mid-2018, the Commander and second-in-Command of the Cayman Islands Coast Guard were appointed.", "Commander Robert Scotland was appointed as the first commanding officer and Lieutenant Commander Leo Anglin was appointed as Second-in-Command.In mid-2019, the commander and second-in-command took part in international joint operations with the United States Coast Guard and the Jamaica Defense Force Coast Guard called Operation Riptide.", "This makes it the first deployment for the Cayman Islands Coast Guard and the first in ten years any Cayman Representative has been on a foreign military ship for a counternarcotic operation.In late November 2019, it was announced that the Cayman Islands Coast Guard would become operational in January 2020, with initial total of 21 Coast Guardsmen half of which would come from the joint marine unit, with further recruitment in the new year.", "One of the many taskings of the Coast Guard will be to push enforcement of all laws that apply to the designated Wildlife Interaction Zone.On 5 October 2021, the Cayman Islands Parliament passed the Cayman Islands Coast Guard Act thus establishing the Cayman Islands Coast Guard as a uniformed and disciplined department of Government.===Taxation===No direct taxation is imposed on residents and Cayman Islands companies.", "The government receives the majority of its income from indirect taxation.", "Duty is levied against most imported goods, which is typically in the range of 22% to 25%.", "Some items are exempted, such as baby formula, books, cameras, electric vehicles and certain items are taxed at 5%.", "Duty on automobiles depends on their value.", "The duty can amount to 29.5% up to $20,000.00 KYD CIF (cost, insurance and freight) and up to 42% over $30,000.00 KYD CIF for expensive models.", "The government charges flat licensing fees on financial institutions that operate in the islands and there are work permit fees on foreign labour.", "A 13% government tax is placed on all tourist accommodations in addition to a US$37.50 airport departure tax which is built into the cost of an airline ticket.", "There is a 7.5% sales tax on the proceeds of the sale of the property, payable by the purchaser.", "There are no taxes on corporate profits, capital gains, or personal income.", "There are no estate or death inheritance taxes payable on Cayman Islands real estate or other assets held in the Cayman Islands.The legend behind the lack of taxation comes from the Wreck of the Ten Sail, when multiple ships ran aground on the reef off the north coast of Grand Cayman.", "Local fishermen are said to have then sailed out to rescue the crew and salvage goods from the wrecks.", "It is said that out of gratitude, and due to their small size, King George III then issued the edict that the citizens of the country of the Cayman Islands would never pay tax.", "There is, however, no documented evidence for this story besides oral tradition.===Foreign relations===Postage stamp with a portrait of Queen Elizabeth II, 1953Foreign policy is controlled by the United Kingdom, as the islands remain an overseas territory of the United Kingdom.", "Although in its early days, the Cayman Islands' most important relationships were with Britain and Jamaica, in recent years, as a result of economic dependence, a relationship with the United States has developed.Though the Cayman Islands is involved in no major international disputes, they have come under some criticism due to the use of their territory for narcotics trafficking and money laundering.", "In an attempt to address this, the government entered into the Narcotics Agreement of 1984 and the Mutual Legal Assistance Treaty of 1986 with the United States, to reduce the use of their facilities associated with these activities.", "In more recent years, they have stepped up the fight against money laundering, by limiting banking secrecy, introducing requirements for customer identification and record keeping, and requiring banks to co-operate with foreign investigators.Due to their status as an overseas territory of the UK, the Cayman Islands has no separate representation either in the United Nations or in most other international organisations.", "However, the Cayman Islands still participates in some international organisations, being an associate member of Caricom and UNESCO, and a member of a sub-bureau of Interpol." ], [ "Emergency services", "Access to emergency services is available using 9-1-1, the emergency telephone number, the same number as is used in Canada and the United States.", "The Cayman Islands Department of Public Safety's Communications Centre processes 9-1-1 and non-emergency police assistance, ambulance service, fire service and search and rescue calls for all three islands.", "The Communications Centre dispatches RCIP and EMS units directly; the Cayman Islands Fire Service maintains their own dispatch room at the airport fire station.The police services are handled by the Royal Cayman Islands Police Service.", "The fire services are handled by the Cayman Islands Fire Service.", "There are 4 main hospitals in the Cayman Islands, private and public health in the Cayman Islands with various localised health clinics around the islands." ], [ "Infrastructure", "===Ports===George Town is the port capital of Grand Cayman.", "There are no berthing facilities for cruise ships, but up to four cruise ships can anchor in designated anchorages.", "There are three cruise terminals in George Town, the North, South, and Royal Watler Terminals.", "The ride from the ship to the terminal is about 5 minutes.===Airports and airlines===There are three airports which serve the Cayman Islands.", "The islands' national flag carrier is Cayman Airways, with Owen Roberts International Airport hosting the airline as its hub.• Owen Roberts International Airport• Charles Kirkconnell International Airport• Edward Bodden Airfield===Main highways===There are three highways, as well as crucial feeder roads that serve the Cayman Islands capital city, George Town.", "Residents in the east of the city will rely on the East-West Arterial Bypass to go into George Town; as well as Shamrock Road coming from Bodden Town and the eastern districts.Other main highways and carriageways include:• Linford Pierson Highway (most popular roadway into George Town from the east)• Esterly Tibbetts Highway (serves commuters to the north of the city and West Bay)• North Sound Road (main road for Central George Town)• South Sound Road (used by commuters to the south of the city)• Crewe Road (alternative to taking Linford Pierson Highway)" ], [ "Education", "===Primary and secondary schools===The Cayman Islands Education Department operates state schools.", "Caymanian children are entitled to free primary and secondary education.", "There are two public high schools on Grand Cayman, John Gray High School and Clifton Hunter High School, and one on Cayman Brac, Layman E. Scott High School.", "Various churches and private foundations operate several private schools.===Colleges and universities===The University College of the Cayman Islands has campuses on Grand Cayman and Cayman Brac and is the only government-run university on the Cayman Islands.The International College of the Cayman Islands is a private college in Grand Cayman.", "The college was established in 1970 and offers associate's, bachelor's and master's degree programmes.", "Grand Cayman is also home to St. Matthew's University, which includes a medical school and a school of veterinary medicine.", "The Cayman Islands Law School, a branch of the University of Liverpool, is based on Grand Cayman.The Cayman Islands Civil Service College, a unit of the Cayman Islands government organised under the Portfolio of the Civil Service, is in Grand Cayman.", "Co-situated with University College of the Cayman Islands, it offers both degree programs and continuing education units of various sorts.", "The college opened in 2007 and is also used as a government research centre.There is a University of the West Indies Open campus in the territory." ], [ "Sports", "Truman Bodden Sports Complex is a multi-use complex in George Town.", "The complex is separated into an outdoor, six-lane swimming pool, full purpose track and field and basketball/netball courts.", "The field surrounded by the track is used for association football matches as well as other field sports.", "The track stadium holds 3,000 people.Association football is the national and most popular sport, with the Cayman Islands national football team representing the Cayman Islands in FIFA.The Cayman Islands Basketball Federation joined the international basketball governing body FIBA in 1976.The country's national team attended the Caribbean Basketball Championship for the first time in 2011.Cayman Islands National Male National Team has won back-to-back Gold Medal victories in 2017 and 2019 Natwest Island Games.Rugby union is a developing sport, and has its own national men's team, women's team, and Sevens team.", "The Cayman Men's Rugby 7s team is second in the region after the 2011 NACRA 7s Championship.The Cayman Islands are a member of FIFA, the International Olympic Committee and the Pan American Sports Organisation, and also competes in the biennial Island Games.The Cayman Islands are a member of the International Cricket Council which they joined in 1997 as an Affiliate, before becoming an Associate member in 2002.The Cayman Islands national cricket team represents the islands in international cricket.", "The team has previously played the sport at first-class, List A and Twenty20 level.", "It competes in Division Five of the World Cricket League.Squash is popular in the Cayman Islands with a vibrant community of mostly ex-pats playing out of the 7-court South Sound Squash Club.", "In addition, the women's professional squash association hosts one of their major events each year in an all-glass court being set up in Camana Bay.", "In December 2012, the former Cayman Open will be replaced by the Women's World Championships, the largest tournament in the world.", "The top Cayman men's player, Cameron Stafford is No.", "2 in the Caribbean and ranked top 200 on the men's professional circuit.Flag football (CIFFA) has men's, women's, and mixed-gender leagues.Other organised sports leagues include softball, beach volleyball, Gaelic football and ultimate frisbee.The Cayman Islands Olympic Committee was founded in 1973 and was recognised by the IOC (International Olympic Committee) in 1976.In April 2005 Black Pearl Skate Park was opened in Grand Cayman by Tony Hawk.", "At the time the park was the largest in the Western Hemisphere.In February 2010, the first purpose-built track for kart racing in the Cayman Islands was opened.", "Corporate karting Leagues at the track have involved widespread participation with 20 local companies and 227 drivers taking part in the 2010 Summer Corporate Karting League.Cydonie Mothersille was the first track and field athlete from the country to make an Olympic final at the 2008 Olympic Games.", "She also won a bronze medal in the 200m at the 2001 World Championships in Athletics and gold in the same event at the 2010 Commonwealth Games." ], [ "Arts and culture", "=== Music ===The Cayman National Cultural Foundation manages the F.J. Harquail Cultural Centre and the US$4 million Harquail Theatre.", "The Cayman National Cultural Foundation, established in 1984, helps to preserve and promote Cayman folk music, including the organisation of festivals such as the Cayman Islands International Storytelling Festival, the Cayman JazzFest, Seafarers Festival and Cayfest.", "The jazz, calypso and reggae genres of music styles feature prominently in Cayman music as celebrated cultural influences.=== Art ===The National Gallery of the Cayman Islands is an art museum in George Town.", "Founded in 1996, NGCI is an arts organisation that seeks to fulfil its mission through exhibitions, artist residencies, education/outreach programmes and research projects in the Cayman Islands.", "The NGCI is a non-profit institution, part of the Ministry of Health and Culture." ], [ "Media", "There are two print newspapers currently in circulation throughout the islands: the ''Cayman Compass'' and ''The Caymanian Times''.", "Online news services include Cayman Compass, Cayman News Service, Cayman Marl Road, The Caymanian Times and Real Cayman News.", "Olive Hilda Miller was the first paid reporter to work for a Cayman Islands newspaper, beginning her career on the ''Tradewinds'' newspaper, which her work helped to establish.Local radio stations are broadcast throughout the islands.Feature films that have been filmed in the Cayman Islands include: ''The Firm'', ''Haven'', ''Cayman Went'' and ''Zombie Driftwood''.Television in the Cayman Islands consist of three over-the-air broadcast stations, Trinity Broadcasting Network - CIGTV (the government-owned channel) - Seventh Day Adventist Network.", "Cable television is available in the Cayman Islands through three providers, C3 Pure Fibre - FLOW TV - Logic TV.", "Satellite television is provided by Dish Direct TV.Broadband is widely available on the Cayman Islands, with Digicel, C3 Pure Fibre, FLOW and Logic all providing super fast fibre broadband to the islands." ], [ "Notable Caymanians" ], [ "See also", "*Outline of the Cayman Islands* Index of Cayman Islands–related articles" ], [ "References" ], [ "Further reading", "* * * ''Originally from the CIA World Factbook 2000.", "''* *" ], [ "External links", "* * Cayman Islands Government* Cayman Islands Department of Tourism* * Cayman Islands Film Commission (archived 22 July 2011)* Cayman Islands.", "''The World Factbook''.", "Central Intelligence Agency.", "* Cayman Islands from ''UCB Libraries GovPubs'' (archived 7 April 2008)* * Cayman National Cultural Foundation" ] ]

[ [ "History of the Cayman Islands" ], [ "Introduction", "Cayman's abundant Turtles attracted ships and settlers to the islandsThe Cayman Islands are a British overseas territory located in the Caribbean that have been under various governments since their discovery by Europeans.", "Christopher Columbus sighted the Cayman Islands on May 10, 1503, and named them ''Las Tortugas'' after the numerous sea turtles seen swimming in the surrounding waters.", "Columbus had found the two smaller sister islands (Cayman Brac and Little Cayman) and it was these two islands that he named \"Las Tortugas\".The 1523 \"Turin map\" of the islands was the first to refer to them as ''Los Lagartos'', meaning alligators or large lizards, By 1530 they were known as the Caymanes after the Carib word ''caimán'' for the marine crocodile, either the American or the Cuban crocodile, ''Crocodylus acutus'' or ''C.", "rhombifer'', which also lived there.", "Recent sub-fossil findings suggest that ''C.", "rhombifer'', a freshwater species, were prevalent until the 20th century." ], [ "Settlement", "Archaeological studies of Grand Cayman have found no evidence that humans occupied the islands prior to the sixteenth century.The first recorded English visitor was Sir Francis Drake in 1586, who reported that the ''caymanas'' were edible, but it was the turtles which attracted ships in search of fresh meat for their crews.", "Overfishing nearly extinguished the turtles from the local waters.", "Turtles were the main source for an economy on the islands.", "In 1787, Captain Hull of HMS Camilla estimated between 1,200 and 1,400 turtles were captured and sold at seaports in Jamaica per year.", "According to historian Edward Long the inhabitants on Grand Cayman had the principal occupation of turtle-fishery.", "Once Caymanian turtlers greatly reduced the turtle population around the islands they journeyed to the waters of other islands in order to maintain their livelihood.Caymanian folklore explains that the island's first inhabitants were Ebanks and his companion named Bawden (or Bodden), who first arrived in Cayman in 1658 after serving in Oliver Cromwell's army in Jamaica.", "The first recorded permanent inhabitant of the Cayman Islands, Isaac Bodden, was born on Grand Cayman around 1700.He was the grandson of the original settler named Bodden.Most, if not all, early settlers were people who came from outside of the Cayman Islands and were on the fringes of society.", "Due to this, the Cayman Islands have often been described as \"a total colonial frontier society\": effectively lawless during the early settlement years.", "The Cayman Islands remained a frontier society until well into the twentieth century.", "The year 1734 marked the rough beginning period of permanent settlement in Grand Cayman.", "Cayman Brac and Little Cayman were not permanently settled until 1833.A variety of people settled on the islands: pirates, refugees from the Spanish Inquisition, shipwrecked sailors, and slaves.", "The majority of Caymanians are of African, Welsh, Scottish or English descent, with considerable interracial mixing.During the early years, settlements on the north and west sides of Grand Cayman were often subject to raids by Spanish forces coming from Cuba.", "On 14 April 1669, the Spanish Privateer Rivero Pardal completed a successful raid on the village of Little Cayman.", "In the process of the raid, the forces burned twenty dwellings to the ground.Those living on the islands often partook in what is called \"wrecking\".", "Caymanians enticed passing ships by creating objects that piqued sailors' interests.", "Often these objects did not look like other vessels.", "Caymanians made mules or donkeys with lanterns tied to their bodies to walk along the beaches or lit a large bonfire to attract sailors.", "Having very little knowledge of the area, sailors often became stuck on the reefs in the process of reaching a distance to where they could communicate with those on the island.", "Once the ships were stuck on the reefs, islanders took canoes to plunder and salvage the ships under the false pretense of providing assistance." ], [ "British control", "The fully restored Pedro St. James Castle on Grand Cayman IslandEngland took formal control of Cayman, along with Jamaica, under the Treaty of Madrid in 1670 after the first settlers came from Jamaica in 1661–71 to Little Cayman and Cayman Brac.", "These first settlements were abandoned after attacks by Spanish privateers, but English privateers often used the Cayman Islands as a base and in the 18th century they became an increasingly popular hideout for pirates, even after the end of legitimate privateering in 1713.Following several unsuccessful attempts, permanent settlement of the islands began in the 1730s.", "In the early morning hours of February 8, 1794, ten vessels which were part of a convoy escorted by HMS Convert, were wrecked on the reef in Gun Bay, on the East end of Grand Cayman.", "Despite the darkness and pounding surf on the reef, local settlers braved the conditions attempting to rescue the passengers and crew of the fledgling fleet.", "There are conflicting reports, but it is believed that between six, and eight people died that night, among them, the Captain of the Britannia.", "However, the overwhelming majority, more than 450 people, were successfully rescued.", "The incident is now remembered as The Wreck of the Ten Sail.", "Legend has it that among the fleet, there was a member of the British Royal Family on board.", "Most believe it to be a nephew of King George III.", "To reward the bravery of the island's local inhabitants, King George III reportedly issued a decreed that Caymanians should never be conscripted for war service, and shall never be subject to taxation.", "However, no official documentation of this decree has been found.", "All evidence for this being the origin of their tax-free status is purely anecdotal.", "Regardless, the Cayman Islands' status as a tax-free British overseas territory remains to this day.From 1670, the Cayman Islands were effective dependencies of Jamaica, although there was considerable self-government.", "In 1831, a legislative assembly was established by local consent at a meeting of principal inhabitants held at Pedro St. James Castle on December 5 of that year.", "Elections were held on December 10 and the fledgling legislature passed its first local legislation on December 31, 1831.Subsequently, the Jamaican governor ratified a legislature consisting of eight magistrates appointed by the Governor of Jamaica and 10 (later increased to 27) elected representatives.The collapse of the Federation of the West Indies created a period of decolonization in the English-speaking Caribbean.", "In regards to independence, of the six dependent territories, the Cayman Islands were the most opposed because it lacked the natural resources needed.", "This opposition came from the fear that independence might prevent any special United States visas that aided Caymanian sailors working on American ships and elsewhere in the United States.", "The people had concerns about their economic viability if the country was to become independent.", "The Cayman Islands were not the only smaller British territory that was reluctant in regards to gaining independence.", "The United Kingdom authorities established a new governing constitution framework for the reluctant territories.", "In place of the Federation of the West Indies, a constitution was created that allowed for the continuation of formal ties with London.", "In the Cayman Islands, the Governor's only obligation to the British Crown is that of keeping the Executive Council informed." ], [ "Slavery", "Grand Cayman was the only island of the three that had institutionalized slavery.", "Although slavery was instituted, Grand Cayman did not have violent slave revolts.", "While scholars tend to agree that to an extent a slave society existed on at least Grand Cayman, there are debates among them on how important slavery was to the society as a whole.", "The slave period for the Cayman Islands lasted between 1734 and 1834.In 1774, George Gauld estimated that approximately four hundred people lived on Grand Cayman; half of the inhabitants were free while the other half were constituted slaves.", "By 1802, of 933 inhabitants, 545 people were owned by slave owners.", "An April 1834 census recorded a population of 1,800 with roughly 46 percent considered free Caymanians.", "By the time of emancipation, enslaved people outnumbered that of slave owners or non-enslaved people on Grand Cayman.", "In 1835, Governor Sligo arrived in Cayman from Jamaica to declare all enslaved people free in accordance with the British Slavery Abolition Act 1833.Caymanian settlers resented their administrative association with Jamaica, which caused them to seize every opportunity to undermine the authorities.", "This problematic relationship reached its peak during the period leading up to emancipation in 1835.Caymanian slave owners who did not want to give up the free labour they extracted from their human chattel refused to obey changes in British legislation outlawing slavery.", "In response to the Slave Trade Act 1807, the Slave Trade Felony Act 1811, and the Emancipation Act 1834, slave owners organized resistance efforts against the authorities in Jamaica.Local White residents of the Cayman Islands also resisted the stationing of troops of the West India Regiment.", "This animosity stemmed from the fact that the West India Regiment enlisted Black men, which the White establishment opposed because they were 'insulted' at the idea of Black soldiers defending their settlements." ], [ "Dependency of Jamaica", "The Cayman Islands were officially declared and administered as a dependency of Jamaica from 1863 but were rather like a parish of Jamaica with the nominated justices of the peace and elected vestrymen in their Legislature.", "From 1750 to 1898 the Chief Magistrate was the administrating official for the dependency, appointed by the Jamaican governor.", "In 1898 the Governor of Jamaica began appointing a Commissioner for the Islands.", "The first Commissioner was Frederick Sanguinetti.", "In 1959, upon the formation of the Federation of the West Indies the dependency status with regards to Jamaica ceased officially although the Governor of Jamaica remained the Governor of the Cayman Islands and had reserve powers over the islands.", "Starting in 1959 the chief official overseeing the day-to-day affairs of the islands (for the Governor) was the Administrator.", "Upon Jamaica's independence in 1962, the Cayman Islands broke its administrative links with Jamaica and opted to become a direct dependency of the British Crown, with the chief official of the islands being the Administrator.In 1953 the first airfield in the Cayman Islands was opened as well as the George Town Public hospital.", "Barclays ushered in the age of formalised commerce by opening the first commercial bank." ], [ "Governmental changes", "Following a two-year campaign by women to change their circumstances, in 1959 Cayman received its first written constitution which, for the first time, allowed women to vote.", "Cayman ceased to be a dependency of Jamaica.During 1966, legislation was passed to enable and encourage the banking industry in Cayman.In 1971, the governmental structure of the islands was again changed, with a governor now running the Cayman Islands.", "Athel Long CMG, CBE was the last administrator and the first governor of the Cayman Islands.In 1991, a review of the 1972 constitution recommended several constitutional changes to be debated by the Legislative Assembly.", "The post of chief secretary was reinstated in 1992 after having been abolished in 1986.The establishment of the post of chief minister was also proposed.", "However, in November 1992 elections were held for an enlarged Legislative Assembly and the Government was soundly defeated, casting doubt on constitutional reform.", "The \"National Team\" of government critics won 12 (later reduced to 11) of the 15 seats, and independents won the other three, after a campaign opposing the appointment of chief minister and advocating spending cuts.", "The unofficial leader of the team, Thomas Jefferson, had been the appointed financial secretary until March 1992, when he resigned over public spending disputes to fight the election.", "After the elections, Mr. Jefferson was appointed minister and leader of government business; he also held the portfolios of Tourism, Aviation and Commerce in the executive council.", "Three teams with a total of 44 candidates contested the general election held on November 20, 1996: the governing National Team, Team Cayman and the Democratic Alliance Group.", "The National Team were returned to office but with a reduced majority, winning 9 seats.", "The Democratic Alliance won 2 seats in George Town, Team Cayman won one in Bodden Town and independents won seats in George Town, Cayman Brac and Little Cayman.Although all administrative links with Jamaica were broken in 1962, the Cayman Islands and Jamaica continue to share many links, including a common united church (the United Church in Jamaica and the Cayman Islands) and Anglican diocese (although there is debate about this).", "They also shared a common currency until 1972.In 1999, 38–40% of the expat population of the Cayman Islands was of Jamaican origin and in 2004/2005 little over 50% of the expatriates working in the Cayman Islands (i.e.", "8,000) were Jamaicans (with the next largest expatriate communities coming from the United States, United Kingdom and Canada)." ], [ "Hurricane Ivan", "Ivan damage in the Cayman IslandsIn September 2004, The Cayman Islands were hit by Hurricane Ivan, causing mass devastation, loss of animal life (both wild and domestic/livestock) and flooding; however, there was no loss of human life.", "Some accounts reported that the majority of Grand Cayman had been underwater and with the lower floors of some buildings being completely flooded in excess of 8 ft. An Ivan Flood Map is available from the Lands & Survey Dept.", "of The Cayman Islands indicating afflicted areas and their corresponding flood levels.", "This natural disaster also led to the bankruptcy of a heavily invested insurance company called Doyle.", "The company had re-leased estimates covering 20% damage to be re-insured at minimal fees when in fact the damage was over 65% and every claim was in the millions.", "The company simply could not keep paying out and the adjusters could not help lower the payments due to the high building code the Islands adhere to.Much suspense was built around the devastation that Hurricane Ivan had caused as the leader of Government business Mr. Mckeeva Bush decided to close the Islands to any and all reporters, aid and denied permissions to land any aircraft except for Cayman Airways.", "The line of people wishing to leave, but unable to do so, extended from the airport to the post office each day, as thousands who were left stranded with no shelter, food, or fresh water hoped for a chance to evacuate.", "As a result, most evacuations and the mass exodus which ensued in the aftermath was done so by private charter through personal expense, with or without official permission.", "It was also a collective decision within the government at that time to turn away two British warships that had arrived the day after the storm with supplies.", "This decision was met by outrage from the Islanders who thought that it should have been their decision to make.", "Power and water was cut off due to damaged pipes and destroyed utility poles, with all utilities restored to various areas over the course of the next three months.", "Fortis Inc., a Canadian-owned utility company, sent a team down to Grand Cayman to assist the local power company, CUC, with restoration.", "The official report, extent of damage, duration and recovery efforts in the words of Mr. Bush himself are first recorded a month following to the Select Committee on Foreign Affairs Written Evidence, Letter from the Cayman Islands Government Office in the United Kingdom, 8 October 2004.", "\"Hurricane Ivan weakened to a category four hurricane as it moved over Grand Cayman.", "It is the most powerful hurricane ever to hit the cayman islands.", "The eye of the storm passed within eight to 15 miles of Grand Cayman.", "It struck on Sunday 12 September, bringing with it sustained winds of 155 miles per hour, gusts of up to 217 mph, and a storm surge of sea water of eight to 10 feet, which covered most of the Island.", "A quarter of Grand Cayman remained submerged by flood waters two days later.", "Both Cayman Brac and Little Cayman suffered damage, although not to the same extent as Grand Cayman.Damage on Grand Cayman has been extensive.", "\"I include with this letter, for your reference, a detailed briefing about the damage and the recovery effort, and some photographs of the devastation.", "95% of our housing stock has sustained damage, with around 25% destroyed or damaged beyond repair.", "We currently have 6,000 homes that are uninhabitable-these are homes that house teachers, nurses, manual and other workers.", "Thankfully, loss of life in Cayman has been limited, relative to the impact of the storm.", "\"- Honourable McKeeva Bush, OBE, JP.While there still remains visible signs of damage, in the vegetation and destruction to buildings particularly along the southern and eastern coastal regions, the Island took considerable time to become suitable as a bustling financial & tourism destination again.", "There remain housing issues for many of the residents as of late 2005, with some buildings still lying derelict due to insurance claims as of 2013, feasibility, new regulations and building codes.", "Many residents simply were unable to rebuild, and abandoned the damaged structures." ], [ "References" ], [ "External links" ] ]