King (chess)

The king (♔, ♚) is the most important piece in the game of chess. It may move to any adjoining square; it may also perform, in tandem with the rook, a special move called castling. 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 immediately. If this cannot be done, the king is said to be in checkmate, resulting in a loss for that player. A player cannot make any move that places their own king in check. Despite this, the king can become a strong offensive piece in the endgame or, rarely, the middlegame.

Quotes

 * The King himself is haughty care, Which overlooketh all his men, And when he seeth how they fare,  He steps among them now and then;    Whom, when his foe presumes to check,    His servants stand to give the neck.
 * Nicholas Breton, "The Chess Play" (1593), The King