Chess strategy is the aspect of chess play concerned with evaluation of chess positions and setting goals and long-term plans for future play. While evaluating a position strategically, a player must take into account such factors as the relative value of the pieces on the board, pawn structure, king safety, position of pieces, and control of key squares and groups of squares. Chess strategy is distinguished from chess tactics, which is the aspect of play concerned with the move-by-move setting up of threats and defenses. Some authors distinguish static strategic imbalances, which tend to persist for many moves, from dynamic imbalances, which are temporary. This distinction affects the immediacy with which a sought-after plan should take effect. Until players reach the skill level of "master", chess tactics tend to ultimately decide the outcomes of games more often than strategy. Many chess coaches thus emphasize the study of tactics as the most efficient way to improve one's results in serious chess play.
The pawn is the most numerous and weakest piece in the game of chess. It may move one square directly forward, it may move two 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. The white pawns start on a2 through h2; the black pawns start on a7 through h7.
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.
Madrasi chess is a chess variant invented in 1979 by Abdul Jabbar Karwatkar. The game uses the conventional rules of chess with the addition that when a piece is attacked by a piece of the same type but opposite colour it is paralysed and becomes unable to move, capture or give check.
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.
In the game of chess, interference occurs when the line between an attacked piece and its defender is interrupted by sacrificially interposing a piece. It is a chess tactic which seldom arises, and is therefore often overlooked. Opportunities for interference are rare because the defended object must be more valuable than the sacrificed piece, and the interposition must itself present a threat. Huczek defines interference as a tactic involving blocking moves that obstruct lines of attack. This definition may be expanded by including blocking moves that disrupt lines of defense.
In chess, a tactic is a sequence of moves that each makes one or more immediate threats – a check, a material threat, a checkmating sequence threat, or the threat of another tactic – that culminates in the opponent's being unable to respond to all of the threats without making some kind of concession. Most often, the immediate benefit takes the form of a material advantage or mating attack; however, some tactics are used for defensive purposes and can salvage material that would otherwise be lost, or to induce stalemate in an otherwise lost position.
In chess and similar games, check is a condition that occurs when a player's king is under threat of capture on the opponent's next turn. A king so threatened is said to be in check. A player must get out of check if possible by moving the king to an unattacked square, interposing a piece between the threatening piece and the king, or capturing the threatening piece. If the player cannot remove the check by any of these options, the game ends in checkmate and the player loses. Players cannot make any move that puts their own king in check.
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.
In chess, an isolated pawn is a pawn that has no friendly pawn on an adjacent file. Isolated pawns are usually a weakness because they cannot be protected by other pawns. The square in front of the pawn may become a good outpost for the opponent to anchor pieces. Isolated pawns most often become weaker in the endgame, as there are fewer pieces available to protect the pawn.
In chess, promotion is the replacement of a pawn with a new piece when the pawn is moved to its last rank. The player replaces the pawn immediately with a queen, rook, bishop, or knight of the same color. The new piece does not have to be a previously captured piece. Promotion is mandatory when moving to the last rank; the pawn cannot remain as a pawn.
Tsume shogi or tsume (詰め) is the Japanese term for a shogi miniature problem in which the goal is to checkmate the opponent's king. Tsume problems usually present a situation that might occur in a shogi game, and the solver must find out how to achieve checkmate. It is similar to a mate-in-n chess problem.
In chess, a fortress is an endgame drawing technique in which the side behind in material sets up a zone of protection that the opponent cannot penetrate. This might involve keeping the enemy king out of one's position, or a zone the enemy cannot force one out of. An elementary fortress is a theoretically drawn position with reduced material in which a passive defense will maintain the draw.
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.
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.
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.
In chess, a skewer is a tactic in which a long range attacker attacks two targets on the same rank, file or diagonal; and is similar to a pin. A skewer is often considered to be the opposite of a pin; the supposed difference is that in a skewer, the more valuable piece is the one under direct attack and the less valuable piece is behind it. The opponent is compelled to move the more valuable piece to avoid its capture, thereby exposing the less valuable piece which can then be captured. However, this is not quite a full and accurate understanding of a skewer, because two pieces of equal value can be subjected to a skewer. For example, two bishops standing on the same rank or file can be skewered by a rook; or two rooks on the same diagonal can be skewered by a bishop. Only line pieces can skewer; kings, knights, and pawns cannot.
The following outline is provided as an overview of and topical guide to chess:
Many basic tactics of shogi are similar to those of chess tactics, involving forks, pins, removing the defender and other techniques, all of which are considered very strong when used effectively.
