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Chess is an abstract strategy board game and mental sport for two players. The object of the game is to checkmate the opponent's king. This occurs when the king is under immediate attack (in check) and there is no way to prevent it from being captured on the next move. Chess is one of the world's most popular board games; it is played both recreationally and competitively in clubs, tournaments, online, and by mail or e-mail (correspondence chess). Many variants and relatives of chess are played throughout the world. The most popular, in descending order by number of players, are xiangqi in China, shogi in Japan, janggi in Korea, and makruk in Thailand. The game described in this article is sometimes known as FIDE Chess, Western Chess or International Chess to distinguish it from other variants.
Overview of the game Chess is played on a square board of 8 rows (called ranks) and 8 columns (called files) of squares. The 64 squares' colors alternate between light and dark, and are referred to as "light squares" and "dark squares". Each player begins the game with 16 pieces which can move in defined directions, and in some instances, limited range, and can remove (capture) other pieces from the board: each player's pieces comprise 8 pawns, 2 knights, 2 bishops, 2 rooks, 1 queen and 1 king. One player controls the white pieces and the other player controls the black pieces; the player that controls white is always the first player to move. The players alternate moving one piece at a time (with one important exception) to either an unoccupied square, or one occupied by an opponent's piece, capturing it; with one rare exception, all pieces capture opponent's pieces by moving to the square that the opponent's piece occupies. When a king is directly threatened with capture by one or more of the opponent's pieces, the player is said to be in ''check''. When in check, only moves that remove the threat of the king's capture are permitted. The object of the game is to checkmate the opponent; this occurs when the opponent's king is in check, and no move can be made that would subsequently prevent the king's capture. Normally a checkmate will require the cooperation of several pieces, but can also be achieved with one. A player who deems checkmate is inevitable may concede the game (resign) to the other player. A drawn result (a tie) is also possible. Chess has been described not only as a game but also as an art, a science, and a sport. It is sometimes seen as an abstract war game; as a "mental martial art", and teaching chess has been advocated as a way of enhancing mental prowess. Rules of chess Main article: Rules of chess When a game begins, one player controls the sixteen white pieces while the other uses the sixteen black pieces. The colors are chosen either by a friendly agreement, by a game of chance such as pick-a-hand, or by a tournament director. The first player, referred to as White, always moves first and therefore has a slight advantage over the second player, referred to as Black. The chessboard is placed so that each player has a white square in the near right hand corner, and the pieces are set out as shown in the diagram, with each queen on a square that matches its color. Each kind of chess piece moves a different way. The rook (colloquially known as a "castle") moves any number of vacant spaces vertically or horizontally, while the bishop moves any number of vacant spaces in any direction diagonally (meaning a bishop will always remain on the same color; note that each side has a bishop for each colored square, and between them they cover the whole board. Losing one bishop often creates weaknesses on the same colored square as the lost bishop). The queen is a combination of the rook and bishop (it can move any number of spaces diagonally, horizontally, or vertically). The king can move only one square horizontally, vertically, or diagonally except when a player castles. The knight can jump over occupied squares and moves two spaces horizontally and one space vertically (or vice versa), making an L shape; a knight in the middle of the board has eight squares to which it can move. Note that every time a knight moves, it changes square color. With the exception of the knight, pieces cannot jump over each other. One's own pieces ("friendly pieces") cannot be passed if they are in the line of movement, and a friendly piece can never replace another friendly piece. Enemy pieces cannot be passed, but they can be "captured". When a piece is captured (or taken), the attacking piece replaces the enemy piece on its square (en passant being the only exception). The king cannot be captured in regular chess, only put in check. If a player is unable to get the king out of check, checkmate results, with the loss of the game. Pawns are the only pieces that capture differently than they move. They can capture an enemy piece on either of the two spaces adjacent to the space in front of them (i.e., the two squares diagonally in front of them), but cannot move to these spaces if they are vacant. Conversely, a pawn can move forward one square, but only if that square is unoccupied; a pawn can move two squares forward, but only if it has not moved yet, and both squares are empty. When such an initial two square advance is made that puts that pawn horizontally adjacent to an opponent's pawn, the opponent's pawn can capture that pawn ("en passant") as if it moved forward only one square rather than two, and only on the immediately subsequent move. A pawn cannot move backward. If a pawn advances all the way to the eighth rank, it is then promoted (converted) to any other piece of the player's color, except a King or another pawn — in practice, the pawn is almost always promoted to a queen. Chess games do not have to end in checkmate- either player may resign if the situation looks hopeless. Games also may end in a draw (tie). A draw can occur in several situations, including draw by agreement, draw by impossibility of checkmate (usually because of insufficient material to checkmate), stalemate, threefold repetition, or the fifty move rule. Until the 1970s, at least in English-speaking countries, chess games were recorded and published using descriptive chess notation. This has been supplanted by the more compact algebraic chess notation. Several notations have emerged, based upon algebraic chess notation, for recording chess games in a format suitable for computer processing. Of these, Portable Game Notation (PGN) is the most common. Apart from recording games, there is also a notation known as Forsyth-Edwards Notation for recording specific positions. This is useful for adjourning a game to resume later or for conveying chess problem positions without a diagram. Sample game A sample chess game is made to help understand how to play chess and its rules. It explains chess through a simple demonstration, move after move. Please read this sample chess game for details. Strategy and tactics
Alternative ways to play chess
Chess variants
Origins of chess Main article: Origins of chess Many countries claim to have invented chess in some incipient form. The most commonly held view is that chess originated in India, since the Arabic, Persian, Greek, Portuguese and Spanish words for chess are all derived from the Sanskrit game Chaturanga. In addition, in the past only India had all three animals, horse, camel and elephant, in its cavalry, which represent knight, bishop and rook in chess. The present version of chess played throughout the world ultimately derives from a version of Chaturanga that was played in India around the 6th century. It is believed that the Persians subsequently created a more recognizable version of the game called Shatranj. Another theory exists that chess arose from the similar game of Xiangqi (Chinese chess), or at least a predecessor thereof, existing in China since the 2nd century BC. Scholars who have favored this theory include Joseph Needham and David H. Li. Chess eventually spread westward to Europe and eastward as far as Japan, spawning variants as it went. The game spread throughout the Islamic world after the Muslim conquest of Persia. When it entered the Islamic world, the names of its pieces largely retained their Persian forms but its name became shatranj, which continued in Spanish as ajedrez and in Greek as zatrikion, but in most of Europe it was replaced by versions of the Persian word shāh = "king". There is a theory that this name replacement happened because, before the game of chess came to Europe, merchants coming to Europe brought ornamental chess kings as curiosities and with them their name shāh, which Europeans mispronounced in various ways. Chess eventually reached Russia via Mongolia, where it was played at the beginning of the 7th century. It was introduced into the Iberian Peninsula by the Moors in the 10th century, and described in a famous 13th century manuscript covering chess, backgammon, and dice named the Libro de los juegos. The entrance of chess into Europe is marked by an enhancement of the powers of the queen. Origins of chess terms Development of modern chess rules and pieces
Organization of chess
Important chess competitions For most, the ultimate chess competition is the World Chess Championship. From 1993 to 2006, there was no consensus on who owned the title. Vladimir Kramnik was World Champion by natural succession (having defeated the last undisputed World Champion Garry Kasparov in a match, and not having lost a match since), while Veselin Topalov was the official FIDE World Champion, having won the FIDE World Chess Championship 2005. In April 2006 it was announced that these two would play a match to decide a unified title from 21 September to 13 October 2006. Kramnik won this unification match by scoring 2.5-1.5 in a series of four rapidplay tie-break games after the score was tied at 6-6 following the classical time controls. The World Champion is not necessarily the highest-rated player in the world. Topalov is in fact rated number one on the current FIDE rating list. The traditional way in which FIDE arrived at contenders to play the world champion was by means of a long drawn out series of qualification stages. Zonal competitions provided qualifiers for the Interzonal tournament(s) and the highest placed finishers in these contests competed in the Candidates Tournament, effectively a series of knockout matches to produce an eventual winner and challenger for the incumbent champion. Nowadays, zonal qualifiers join the world's elite players in a single knockout tournament, the winner becoming the new champion. In women's chess, the world's highest rated female player Judit Polgar has never participated in the Women's World Chess Championship, instead preferring to compete with the leading men on what is commonly regarded as the elite tournament circuit. Older sister Zsuzsa Polgar is also a very strong player and was Women's World Champion from 1996-1999. The reigning Women's World Champion is Xu Yuhua, from China. Other competitions for individuals include the World Junior Chess Championship, the European Individual Championship and the National Chess Championships of countries around the world. On the invitational or 'elite' tournament circuit, Spain's Linares chess tournament is undoubtedly one of the world's finest. Sometimes described as the 'Wimbledon' of chess, it is very popular with the world's leading grandmasters. Popular too, are Monte Carlo's Melody Amber tournament, the Dortmund Sparkassen Chess Meeting and Wijk aan Zee's Corus chess tournament. Regular team chess events include the Chess Olympiad and European Team Championship. In view of the longstanding Soviet domination of these events, highly publicised and prestigious Russia (USSR) vs Rest of the World matches were arranged in 1970, 1984 and 2002 to provide a sterner challenge to Russian hegemony. The World Chess Solving Championship is both a team and an individual event. Computer chess Main article: Computer chess Serious work on machines that play chess has been going on since 1890 citation needed, and chess-playing computer programs featured prominently in the artificial intelligence boom of the 1950s - 1970s. At first considered only a curiosity, the best chess playing programs — like Shredder, Fritz etc. — have become extremely strong players. In blitz chess, they can beat the best human players; at regular time controls, however, battles between the very best chess programs and the very best human players have been tantalizingly finely balanced. However, it is important to note that the method by which computer programs play chess does not really resemble the way humans play chess — the computer simply calculates the board position after every possible combination of legal moves and acts accordingly, whereas human masters act more from intuition and pattern recognition. Moreover, as CPU speed and memory become less expensive, computer chess programs can search ever larger numbers of moves in the same amount of time, and store ever larger databases of opening and endgame positions. Nor has the study of chess proven particularly useful in the broader AI field; the methods used to play high-level chess are very different to the ones used for machine learning, machine vision, and the like. The Association for Computing Machinery (ACM) held the first major chess tournament for computers, the 1st United States Computer Chess Championship, in September 1970. CHESS 3.0, a chess program from Northwestern University, won the championship. Garry Kasparov, then ranked number one in the world, played a six-game match against IBM's chess computer Deep Blue in February 1996. Deep Blue shocked the world by winning the first game in Deep Blue - Kasparov, 1996, Game 1, but Kasparov convincingly won the match by winning three games and drawing two. The six-game rematch in May 1997 was won by the machine (informally dubbed Deeper Blue) which was subsequently retired by IBM. Controversies arose after the match when Kasparov accused IBM of using human intervention, which IBM denied. It has often been claimed that IBM withheld the computer logs showing Deep Blue's "thinking" but in fact the logs were published shortly after the end of the match. In October 2002, Vladimir Kramnik drew in an eight-game match with the computer program Deep Fritz. In 2003, Kasparov drew both a six-game match with the computer program Deep Junior in February, and a four-game match against X3D Fritz in November. The chess machine Hydra is the intellectual descendant of Deep Blue; and appears to be somewhat stronger than Deep Blue was. Certainly it is very much comparable in terms of positions analysed per second. Given the relative ease with which it beats the other programs, and the humans it has met, Hydra may be expected to beat any unaided human player in match play. In June 2005, Hydra scored a decisive victory over the then 7th ranked GM Michael Adams winning five games and drawing one game in a six game match. Whilst too few games have been played to establish this, and neither Kramnik or Kasparov have played Hydra, Hydra's creators estimate its rating should be over 3000. Kasparov's loss to Deep Blue has inspired the creation of chess variants in which human intelligence can still overpower computer calculation. In particular Arimaa, which is played upon a standard 8×8 chessboard, is a game at which humans can beat the best efforts of programmers so far, even at fast time controls. See also Learning chess Chess news Collections of games Free chess software See | |||||||||||||||||||||||||||||||||||||
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