A chess piece, or chessman, is a game piece that is placed on a chessboard to play the game of chess. It can be either white or black, and it can be one of six types: king, queen, rook, bishop, knight, or pawn.
The pawn is the most numerous and weakest piece in the game of chess. It may move one vacant square directly forward, it may move two vacant squares directly forward on its first move, and it may capture one square diagonally forward. Each player begins a game with eight pawns, one on each square of their second rank.
In chess, a pin is a chess tactic in which a defending piece cannot move without exposing a more valuable defending piece on its other side to capture by the attacking piece. Moving the attacking piece to bring on the pin is called pinning; the defending piece so restricted is described as pinned. Only pieces that can move an indefinite number of squares in a horizontal, vertical, or diagonal line can pin. Kings, knights, and pawns cannot pin. Any piece can be pinned except the king, since the king must be immediately removed from check under all circumstances. It is like a skewer, but in a skewer, the more valuable piece is the one under direct attack.
The rules of chess govern the play of the game of chess. Chess is a two-player abstract strategy board game. Each player controls sixteen pieces of six types on a chessboard. Each type of piece moves in a distinct way. The object of the game is to checkmate the opponent's king. A game can end in various ways besides checkmate: a player can resign, and there are several ways in which a game can end in a draw.
Bughouse chess is a popular chess variant played on two chessboards by four players in teams of two. Normal chess rules apply, except that captured pieces on one board are passed on to the teammate on the other board, who then has the option of putting these pieces on their board.
This glossary of chess explains commonly used terms in chess, in alphabetical order. Some of these terms have their own pages, like fork and pin. For a list of unorthodox chess pieces, see Fairy chess piece; for a list of terms specific to chess problems, see Glossary of chess problems; for a list of named opening lines, see List of chess openings; for a list of chess-related games, see List of chess variants.
In the game of chess, perpetual check is a situation in which one player can force a draw by an unending series of checks. This typically arises when the player who is checking cannot deliver checkmate, and failing to continue the series of checks gives the opponent at least a chance to win. A draw by perpetual check is no longer one of the rules of chess; however, such a situation will eventually allow a draw claim by either threefold repetition or the fifty-move rule. Players usually agree to a draw long before that, however.
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.
Progressive chess is a chess variant in which players, rather than just making one move per turn, play progressively longer series of moves. The game starts with White making one move, then Black makes two consecutive moves, White replies with three, Black makes four and so on. Progressive chess can be combined with other variants; for example, when Circe chess is played as a game, it is usually progressively. Progressive chess is considered particularly apt for playing correspondence chess using mail or some other slow medium, because of the relatively small number of moves in a typical game.
The en passant capture is a move in chess. It consists of a pawn capturing a horizontally adjacent enemy pawn that has just advanced two squares in one move. The capturing pawn moves to the square that the enemy pawn passed over, as if the enemy pawn had advanced only one square. Such a capture is permitted only on the turn immediately after the two-square advance; it cannot be done on a later turn.
Dark chess is a chess variant with incomplete information, similar to Kriegspiel. It was invented by Jens Bæk Nielsen and Torben Osted in 1989. A player does not see the entire board – only their own pieces and the squares that they can legally move to.
Vernon Rylands Parton was an English chess enthusiast and prolific chess variant inventor, his most renowned variants being Alice chess and Racing Kings. Many of Parton's variants were inspired by the fictional characters and stories in the works of Lewis Carroll. Parton's formal education background, like Lewis Carroll's, was in mathematics. Parton's interests were wide and he was a great believer in Esperanto.
In chess, promotion is the replacement of a pawn with a new queen, rook, bishop, or knight of the same color. It occurs immediately when the pawn moves to its last rank, with the player choosing the piece of promotion. The new piece does not have to be a previously captured piece. Promotion is mandatory; the pawn cannot remain as a pawn.
Dice chess can refer to a number of chess variants in which dice are used to alter gameplay; specifically that the moves available to each player are determined by rolling a pair of ordinary six-sided dice. There are many different variations of this form of dice chess. One of them is described here.
Hexagonal chess refers to a group of chess variants played on boards composed of hexagon cells. The best known is Gliński's variant, played on a symmetric 91-cell hexagonal board.
Omega Chess is a commercial chess variant designed and released in 1992 by Daniel MacDonald. The game is played on a 10×10 board with four extra squares, each added diagonally adjacent to the corner squares. The game is laid out like standard chess with the addition of a champion in each corner of the 10×10 board and a wizard in each new added corner square.
The following outline is provided as an overview of and topical guide to chess:
EuroShogi is a shogi variant invented by Vladimír Pribylinec starting in 2000. The game developed from an early version of chess variant Echos in 1977, leading to Cubic Chess, then later to Cubic Shogi, and finally to EuroShogi. Instead of the classic figures, 18 black and 18 black cubes are used, which are on two opposing sides without symbols. The other two cubes on the opposite sides have one white and one black symbol. The other opposing sides are the same symbols of the opposite color - their promotion is indicated by a circle around symbol. Symbol on top of its mobility. The pieces are placed on the board so that they are oriented towards players without any symbolic surfaces. Plays on a board with 8x8 fields of the same color.
Hostage chess is a chess variant invented by John A. Leslie in 1997. Captured pieces are not eliminated from the game but can reenter active play through drops, similar to shogi. Unlike shogi, the piece a player may drop is one of their own pieces previously captured by the opponent. In exchange, the player returns a previously captured enemy piece which the opponent may drop on a future turn. This is the characteristic feature of the game.
