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For other meanings, see Chess (disambiguation).
From left, a white , black and , white , black , and white .
From left, a white king, black rook and queen, white pawn, black knight, and white bishop.

Chess (from the Persian word Shah) is a board game and mental sport for two players. It is played on a square board of 8 rows (called ranks) and 8 columns (called files), giving 64 squares of alternating colour, light and dark. Each player begins the game with 16 pieces that each move and capture other pieces on the board in a unique way: eight pawns, two knights, two bishops, two rooks, one queen and one king. One player controls the white pieces; the other player controls the black pieces. The object of the game is to achieve checkmate. This occurs when a king is attacked and it cannot escape capture. Note that checkmate renders the actual capture of the king unnecessary since it is a foregone conclusion and the game ends at that time.



Chess is not a game of chance; it is based solely on tactics and strategy. Nevertheless, the game is so complex that not even the best players can consider all contingencies: although only 64 squares and 32 pieces are on the board, the number of possible games that can be played far exceeds the number of atoms in the universe (see "Shannon number").

Chess is one of the world's most popular games; it has been described not only as a game, but also as an art, science, and sport. Chess is sometimes seen as an abstract wargame; as a "mental martial art", and teaching chess has been advocated as a way of enhancing mental prowess. Chess is played both recreationally and competitively in clubs, tournaments, online, and by 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), and Janggi (in Korea).


Many countries claim to have invented the chess game in some incipient form. The most commonly held belief is that Chess originated in India, having spawned from the game Chaturanga which appears to have been invented in the 6th century A.D. However, the highly similar game of Chinese chess, or at least a predecessor thereof, is known to have existed in China at least as far back as the 2nd century BC.

Chess eventually spread westward to Europe and eastward as far as Korea, spawning variants as it went. From India it allegedly migrated to Persia, and spread throughout the Islamic world after the Muslim conquest of Persia. Chess eventually reached Russia via Mongolia, where it was played at the beginning of the 7th century. It was introduced into Spain by the Moors in the 10th century, described in a famous manuscript covering chess, backgammon, and dice named the Libro de los juegos. For more on this subject, see origins of chess.

A typical Staunton-design set and
A typical Staunton-design set and clock

Modern chess

Early on, the pieces in European chess had limited movement; bishops could only move by jumping exactly two spaces diagonally, the queen could move only one space diagonally, pawns could not move two spaces on their first move, and there was no castling. By the end of the 15th century, the modern rules for the basic moves had been adopted from Italy: pawns gained the option of moving two squares on their first move and the en passant capture therewith, bishops acquired their modern move, and the queen was made the most powerful piece; consequently modern chess is referred to as "Queen's Chess" or "Mad Queen Chess." The game in Europe since that time has been almost the same as is played today. The current rules were finalized in the early 19th century, except for the exact conditions for a draw.

The most popular piece design, the "Staunton" set, was created by Nathaniel Cook in 1849, endorsed by Howard Staunton, a leading player of the time, and officially adopted by Fédération Internationale des Échecs (FIDE) in 1924.

Chess's international governing body is FIDE, which has presided over the world championship matches for decades. See World Chess Championship for details and a more in-depth history. Most countries of the world have a national chess organization as well. Although chess is not yet an Olympic sport, it has its own Olympiad, held every two years as a team event.


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 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.

Computer chess

Main article: Computer chess

Once solely the province of the human mind, chess is now played by both humans and machines. At first considered only a curiosity, the best chess playing programs like Shredder or Fritz have risen in ability to the point where they can seriously challenge and even defeat the best humans, and regularly defeat the average human Grandmaster.

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. 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.

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 x 8 chessboard, is a game at which humans can beat the best efforts of programmers so far, even at fast time controls.

More information

Famous chess games

History of chess

List of World Champions

"Unofficial" but widely recognized as Champions (pre-championship era):

"Official" Champions:

"Unofficial" but widely accepted as current World Champion:

FIDE World Champions after Garry Kasparov:

Chess literature

Chess in the arts and literature

Computer chess

External links

Last updated: 09-03-2005 18:37:12