chess, game for two players played on a square board composed of 64 square spaces, alternately dark and light in color. Basic Rules The board is positioned so that a light-colored square is in the corner to the right of both players, each of whom is provided with 16 pieces, or chessmen, of black or white color. At the start of the game eight pieces are set down in the horizontal row of squares, or rank, nearest each player. The pieces are: two rooks, or castles, in the corner squares; two knights in the adjoining squares; two bishops next to the knights; the queen on the remaining square corresponding to her color; and the king on the other remaining center square; one pawn sits immediately in front of each of these pieces. Each piece moves according to specific rules and is removed from the board when an opposing piece moves into its square, thus displacing it. The object in chess is to trap, or checkmate, the opponent's king. Students of the game use several systems of notation to describe the moves of the pieces. Over the years of modern chess history, various players have become famous for their openings, middle games, or end games, and many tactics have acquired the names of players or countries of origin, as in the Ruy Lopez opening or the Sicilian defense. History Early History Played throughout the civilized world, chess has fascinated people for centuries. Though it dates to antiquity (some researchers believe terra cotta pieces excavated from Mesopotamia of 6,000 B.C. were used in chess), there is debate as to which culture its origins should be credited. A Dominican friar from Italy wrote a chess treatise in the Middle Ages. Its 1474 translation by Englishman William Caxton standardized play for a short time, but it was not until international play of the next century that rules were widely agreed upon. A Syrian, Philip Stamma

, acclaimed as the pioneer of modern chess technique, helped popularize the game in the middle of the 18th cent. through publications and play that stressed strategy. Modern Tournament Play London was the site of the first modern international chess tournament in 1851. In officially sanctioned modern chess tournaments, players accumulate points won at various levels and can advance toward the top designation of grandmaster. Tournament play uses clocks to limit the time permitted for moves, and the concentration and fatigue of a match require players to be in good physical condition. Outstanding players of their day who were considered world champions were: François Philidor

of France, 1747–95; Alexandre Deschappelles
of France, 1815–21; Louis de la Bourdonnais
of France, 1821–40; and Howard Staunton
of England, 1843–51. Official world champions have included: Adolf Anderssen
of Germany, 1851–58 and 1862–66; Paul C. Morphy
of the United States, 1858–62; Wilhelm Steinitz
of Austria, 1866–94; Emanuel Lasker
of Germany, 1894–1921; José R. Capablanca
of Cuba, 1921–27; Alexander A. Alekhine
of France, 1927–35 and 1937–46; and Mikhail M. Botvinnik
of the USSR, 1948–57, 1958–60, and 1961–63. Players from the USSR and Russia have dominated international play since the late 1940s.

The 1972 World Chess Championship, held in Reykjavík, Iceland, between the American Bobby Fischer

and Boris Spassky, received unprecedented worldwide coverage and boosted the game's popularity. The enigmatic Fischer broke the Soviet stranglehold on the world title in a match reflective of cold war tension. Fischer, however, forfeited the title in 1974, the first player ever to do so, by refusing to play a championship match.

Chess's popularity was enhanced in the 1980s by championship duels between Garry Kasparov

and Anatoly Karpov

. In 1993, Kasparov, who had held the world title since 1985, broke with the International Chess Federation (FIDE), which reinstated Karpov as champion after a playoff. Kasparov, still regarded the best player in the world, lost a match in 1997 to the IBM computer Deep Blue (see artificial intelligence

for a more detailed discussion of the development of computer chess programs), which was then "retired." In 1998, Karpov retained his championship by defeating Viswanathan Anand
of India, but relations with FIDE were further strained when Karpov refused to participate in a 1999 tournament, which was won by the relatively unknown Russian Aleksandr Khalifman. Despite Khalifman's claims on the FIDE championship, by 2000 it was widely recognized that Kasparov was the world's number-one player and that his onetime protégé, the 25-year-old Russian Vladimir Kramnik

, was ranked second. In a 2000 match Kramnik defeated Kasparov in a 16-game match and became the world's top chess master. In 2006, in a world championship reunification match, Kramnik defeated Veselin Topalov

, whom FIDE recognized as world champion in 2005, ending the 13-year dispute over the title. In 2007, however, Anand won the title in tournament play. Bibliography A good book for beginners is Capablanca's A Primer of Chess (1935, repr. 1963). See H. J. R. Murray, A History of Chess (1913, repr. 1962); F. Reinfeld, Complete Book of Chess Stratagems (1958, repr. 1972); D. Hooper and K. Whyld, The Oxford Companion to Chess (1984); R. Eales, Chess (1985).