Samuel Loyd was an American chess player, chess composer, puzzle author, and recreational mathematician. Loyd was born in Philadelphia but raised in New York City.
A chess problem, also called a chess composition, is a puzzle set by the composer using chess pieces on a chess board, which presents the solver with a particular task. For instance, a position may be given with the instruction that White is to move first, and checkmate Black in two moves against any possible defence. A chess problem fundamentally differs from over-the-board play in that the latter involves a struggle between Black and White, whereas the former involves a competition between the composer and the solver. Most positions which occur in a chess problem are 'unrealistic' in the sense that they are very unlikely to occur in over-the-board play. There is a good deal of specialized jargon used in connection with chess problems.
A Babson task is a directmate chess problem with the following properties:
- White has only one key, or first move, that forces checkmate in the stipulated number of moves.
- Black's defences include the promotion of a certain pawn to a queen, rook, bishop, or knight.
- If Black promotes, then the only way for White towards a forced checkmate in the stipulated number of moves is to promote a pawn to the same piece to which Black promoted.
Alice chess is a chess variant invented in 1953 by V. R. Parton which employs two chessboards rather than one, and a slight alteration to the standard rules of chess. The game is named after the main character "Alice" in Lewis Carroll's work Through the Looking-Glass, where transport through the mirror into an alternative world is portrayed on the chessboards by the after-move transfer of chess pieces between boards A and B.
This glossary of chess problems explains commonly used terms in chess problems, in alphabetical order. For a list of unorthodox pieces used in chess problems, see Fairy chess piece; for a list of terms used in chess is general, see Glossary of chess; for a list of chess-related games, see List of chess variants.
A Grimshaw is a device found in chess problems in which two pieces arriving on a particular square mutually interfere with each other. It is named after the 19th-century problem composer Walter Grimshaw. The Grimshaw is one of the most common devices found in directmates.
The Novotny is a device found in chess problems named after a problem from 1854 by Antonín Novotný, though the first example was composed by Henry Turton in 1851. A piece is sacrificed on a square where it could be taken by two different opposing pieces, but whichever makes the capture, it interferes with the other. It is essentially a Grimshaw brought about by a sacrifice on the critical square.
A helpmate is a type of chess problem in which both sides cooperate in order to achieve the goal of checkmating Black. In a helpmate in n moves, Black moves first, then White, each side moving n times, to culminate in White's nth move checkmating Black. Although the two sides cooperate, all moves must be legal according to the rules of chess.
A proof game is a type of retrograde analysis chess problem. The solver must construct a game starting from the initial chess position, which ends with a given position after a specified number of moves. A proof game is called a shortest proof game if no shorter solution exists. In this case the task is simply to construct a shortest possible game ending with the given position.
The Lucena position is one of the most famous and important positions in chess endgame theory, where one side has a rook and a pawn and the defender has a rook. Karsten Müller said that it may be the most important position in endgame theory. It is fundamental in the rook and pawn versus rook endgame. If the side with the pawn can reach this type of position, they can forcibly win the game. Most rook and pawn versus rook endgames reach either the Lucena position or the Philidor position if played accurately. The side with the pawn will try to reach the Lucena position to win; the other side will try to reach the Philidor position to draw.
Marmaduke Wyvill was a leading English chess master and Liberal Party politician. He was among the world's strongest players in the 1840s and 1850s.
The World Chess Championship 1972 was a match for the World Chess Championship between challenger Bobby Fischer of the United States and defending champion Boris Spassky of the Soviet Union. The match took place in the Laugardalshöll arena in Reykjavík, Iceland, and has been dubbed the Match of the Century. Fischer became the first American born in the United States to win the world title, and the second American overall. Fischer's win also ended, for a short time, 24 years of Soviet domination of the World Championship.
Anderssen's Opening is a chess opening defined by the opening move:
A joke chess problem is a puzzle in chess that uses humor as a primary or secondary element. Although most chess problems, like other creative forms, are appreciated for serious artistic themes, joke chess problems are enjoyed for some twist. In some cases the composer plays a trick to prevent a solver from succeeding with typical analysis. In other cases, the humor derives from an unusual final position. Unlike in ordinary chess puzzles, joke problems can involve a solution which violates the inner logic or rules of the game.
The World Chess Championship 2006 was a match between Classical World Chess Champion Vladimir Kramnik and FIDE World Chess Champion Veselin Topalov. The title of World Chess Champion had been split for 13 years. This match, played between September 23 and October 13, 2006, in Elista, Kalmykia, Russia, was to reunite the two World Chess Champion titles and produce an undisputed World Champion.
A reflexmate is a chess problem in which white, moving first, must force black to deliver checkmate within a specified number of moves against his will – with the added condition that if either player can give checkmate, they must. If this condition applies only to Black, it is a semi-reflexmate.
The 1935 World Chess Championship was played between challenger Max Euwe and title-holder Alexander Alekhine. It was played in various cities and towns in the Netherlands from October 3 to December 16. Euwe was the winner by overcoming a three-point deficit as late as the ninth game.
Levitsky versus Marshall, also known as the Gold Coins Game, is a famous game of chess played by Stepan Levitsky and Frank Marshall. It was played in Breslau on July 20, 1912, during the master's tournament of the DSB Congress. According to legend, after Marshall's winning last move of the game, gold coins were tossed onto the board by spectators, although this is contested by other accounts.
The 18th season of the Top Chess Engine Championship began on 4 May 2020 and ended on 3 July 2020. The defending champion was Leela Chess Zero, which defeated Stockfish in the previous season's superfinal. The two season 17 superfinalists qualified again for the superfinal. This time Stockfish won, winning by 7 games (+23−16=61).
