In chess, there are a number of ways that a game can end in a draw, neither player winning. Usually, in tournaments a draw is worth a half point to each player, while a win is worth one point to the victor and none to the loser.
Draws are codified by various rules of chess including stalemate (when the player to move is not in check but has no legal move), threefold repetition (when the same position occurs three times with the same player to move), and the fifty-move rule (when the last fifty successive moves made by both players contain no capture or pawn move). Under the standard FIDE rules, a draw also occurs "in dead position", when no sequence of legal moves can lead to checkmate, most commonly when neither player has sufficient material to checkmate the opponent.
Unless specific tournament rules forbid it, players may agree to a draw at any time. Ethical considerations may make a draw uncustomary in situations where at least one player has a reasonable chance of winning. For example, a draw could be called after a move or two, but this would likely be thought unsporting.
Until 1867, tournament games that were drawn were replayed. The Paris tournament of 1867 had so many drawn games to be replayed that it caused organisational problems. In 1868 the British Chess Association decided to award each player half a point instead of replaying the game (Sunnucks 1970:100).
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