Overview
Checkmate (often shortened to mate) is any game position in chess and other chess-like games in which a player's king is in check (threatened with ) and there is no possible escape. Checkmating the opponent wins the game.
In chess, the king is never actually captured—the player loses as soon as the player's king is checkmated. In formal games, it is usually considered good etiquette to resign an inevitably lost game before being checkmated.
If a player is not in check but has no legal moves, then it is stalemate, and the game immediately ends in a draw. A checkmating move is recorded in algebraic notation using the hash symbol "#", for example: 34.Qg3#.
Examples
A checkmate may occur in as few as two moves on one side with all of the pieces still on the board (as in fool's mate, in the opening phase of the game), in a middlegame position (as in the 1956 game called the Game of the Century between Donald Byrne and Bobby Fischer), or after many moves with as few as three pieces in an endgame position.
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