Chess is a two-player board game played on a chessboard, a square-checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.Each player...
, a fork
is a tactic
In chess, a tactic refers to a sequence of moves which limits the opponent's options and may result in tangible gain. Tactics are usually contrasted with strategy, in which advantages take longer to be realized, and the opponent is less constrained in responding.The fundamental building blocks of...
that uses a single piece to attack multiple pieces at the same time. The attacker usually hopes to gain material by capturing one of the opponent's pieces. The defender often finds himself in a difficult position in which he cannot counter all threats. The attacking piece is known as the forking
piece. Conversely, the pieces that the forking piece is attacking are said to be forked
A piece that is defended can still be forked. In this situation, material gain is still possible, if the forking piece has lower value.
The type of fork is commonly named after the type of forking piece. For example, in a knight fork
, a knight moves to attack two or more opponent's pieces in the same move. Any type of piece may perform a fork, including a king
In chess, the king is the most important piece. The object of the game is to trap the opponent's king so that its escape is not possible . If a player's king is threatened with capture, it is said to be in check, and the player must remove the threat of capture on the next move. If this cannot be...
, and any type of piece can be forked.
Knights are often used for forks; they jump to a position where they simultaneously attack two pieces and cannot be counterattacked.
A queen move also often attacks two pieces at the same time, but this typically gains material only if both pieces are undefended, or if one is undefended and the other is the opposing king. Since the queen is usually more valuable than the pieces it is attacking, it usually only gains material forking undefended pieces. The possibility of a queen fork is a very real threat when the queen is out in the open, as is often the case in an endgame. A fork by a protected queen of the opposing queen and king (or an undefended piece) can be useful if the forking player wants to force an exchange
In the tactics and strategy in the board game of chess, an exchange or trade of chess pieces is series of closely related moves, typically sequential, in which the two players capture each others pieces. Any types of pieces except the kings may possibly be exchanged, i. e. captured in an...
The pawn is the most numerous and weakest piece in the game of chess, historically representing infantry, or more particularly armed peasants or pikemen. Each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces...
can also fork enemy pieces. By moving a pawn forward, it may attack two pieces: one diagonally to the left and the other diagonally to the right. In the diagram to the upper-right, the black pawn is forking the two white rooks.
The term royal fork
is sometimes used to describe the situation where the king and queen are forked – thus being the highest material-gaining fork possible. Another term, the grand fork
, is sometimes used to describe the situation where the king, queen, and one (or both) rooks are forked.
The example to the right is from the first round of the FIDE World Chess Championship 2004
The FIDE World Chess Championship, 2004 was held at the Almahary Hotel in Tripoli, Libya, from June 18 to July 13.It was won by Rustam Kasimdzhanov, who beat Michael Adams in the final by a score of 4½-3½...
between Mohamed Tissir and Alexey Dreev
Alexey Dreev is a chess grandmaster from Russia. His career peak Elo rating was 2705, attained in October 2003 and again in April 2005.He qualified for the Candidates Tournament in 1991, but lost his Quarter Final match to Viswanathan Anand in Madras .Then in the FIDE World Championship...
. After 33... Nf2+ 34. Kg1 Nd3, White resigned. In the final position the black knight forks the white queen and rook, so that after the queen moves away, White will lose the exchange
The exchange in chess refers to a situation in which one player loses a minor piece but captures the opponent's rook. The side which wins the rook is said to have won the exchange, while the other player has lost the exchange, since the rook is usually more valuable...
Forks are often used as part of a combination
In chess, a combination is a sequence of moves, often initiated by a sacrifice, which leaves the opponent few options and results in tangible gain. At most points in a chess game, each player has several reasonable options from which to choose, which makes it difficult to plan ahead except in...
which may involve other types of chess tactics as well.