A chessboard is a gameboard used to play chess. It consists of 64 squares, 8 rows by 8 columns, on which the chess pieces are placed. It is square in shape and uses two colours of squares, one light and one dark, in a chequered pattern. During play, the board is oriented such that each player's near-right corner square is a light square.
The queen is the most powerful piece in the game of chess. It can move any number of squares vertically, horizontally or diagonally, combining the powers of the rook and bishop. Each player starts the game with one queen, placed in the middle of the first rank next to the king. Because the queen is the strongest piece, a pawn is promoted to a queen in the vast majority of cases.
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 knight is a piece in the game of chess, represented by a horse's head and neck. It moves two squares vertically and one square horizontally, or two squares horizontally and one square vertically, jumping over other pieces. Each player starts the game with two knights on the b- and g-files, each located between a rook and a bishop.
Castling is a move in chess. It consists of moving the king two squares toward a rook on the same rank and then moving the rook to the square that the king passed over. Castling is permitted only if neither the king nor the rook has previously moved; the squares between the king and the rook are vacant; and the king does not leave, cross over, or finish on a square attacked by an enemy piece. Castling is the only move in chess in which two pieces are moved at once.
A pin is one of the most powerful tactics in chess in which a defending piece cannot move out of an attacking piece's line of attack without exposing a more valuable defending piece. Moving the attacking piece to effect the pin is called pinning; the defending piece restricted by the pin is described as pinned. Only a piece that can move any number of squares along a horizontal, vertical, or diagonal line can pin. Any piece can be pinned except the king.
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; checkmate occurs when a king is threatened with capture and has no escape. A game can end in various ways besides checkmate: a player can resign, and there are several ways a game can end in a draw.
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; for a list of terms general to board games, see Glossary of board games.
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.
Checkmate is any game position in chess and other chess-like games in which a player's king is in check and there is no possible escape. Checkmating the opponent wins the game.
In chess, a discovered attack is a direct attack revealed when one piece moves out of the way of another. Discovered attacks can be extremely powerful, as the piece moved can make a threat independently of the piece it reveals. Like many chess tactics, they often succeed because the opponent would be unable to meet two threats at once unless one of the attacked pieces can simultaneously move away from its own attack and capture the other attacking piece. While typically the consequence of a discovered attack is the gain of material, they do not have to do this to be effective; the tactic can be used merely to gain a tempo. If the discovered attack is a check, it is called a discovered check.
Metamorphosis I is a woodcut print by the Dutch artist M. C. Escher which was first printed in May, 1937. This piece measures 19.5 cm × 90.8 cm and is printed on two sheets.
Metamorphosis III is a woodcut print by the Dutch artist M. C. Escher created during 1967 and 1968. Measuring 19 cm × 680 cm, this is Escher's largest print. It was printed on thirty-three blocks on six combined sheets and mounted on canvas. This print was partly coloured by hand.
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 and other related games, a double check is a check delivered by two pieces simultaneously. In chess notation, it is almost always represented the same way as a single check ("+"), but is sometimes symbolized by "++". This article uses "++" for double check and "#" for checkmate.
In chess, a pure mate is a checkmate position such that the mated king is attacked exactly once, and prevented from moving to any of the adjacent squares in its field for exactly one reason per square. Each of the squares in the mated king's field is attacked or "guarded" by one—and only one—attacking unit, or else a square which is not attacked is occupied by a friendly unit, a unit of the same color as the mated king. Some authors allow that special situations involving double check or pins may also be considered as pure mate.
A pawnless chess endgame is a chess endgame in which only a few pieces remain, and no pawns. The basic checkmates are types of pawnless endgames. Endgames without pawns do not occur very often in practice except for the basic checkmates of king and queen versus king, king and rook versus king, and queen versus rook. Other cases that occur occasionally are (1) a rook and minor piece versus a rook and (2) a rook versus a minor piece, especially if the minor piece is a bishop.
In chess, several checkmate patterns occur frequently enough to have acquired specific names in chess commentary. By definition, a checkmate pattern is a recognizable/particular/studied arrangements of pieces that delivers checkmate. The diagrams that follow show these checkmates with White checkmating Black.
The following outline is provided as an overview of and topical guide to chess:
