WCheckmate is a game position in chess and other chess-like games in which a player's king is in check and there is no way to avoid the threat. Checkmating the opponent wins the game.
WIn chess, a back-rank checkmate is a checkmate delivered by a rook or queen along a back rank in which the mated king is unable to move up the board because the king is blocked by friendly pieces on the second rank. A typical position is shown to the right.
WThe bishop and knight checkmate in chess is the checkmate of a lone king which can be forced by a bishop, knight, and king. With the stronger side to move and with perfect play, checkmate can be forced in at most thirty-three moves from any starting position where the defender cannot quickly win one of the pieces. The exception is the "stalemate trap". These exceptions constitute about 0.5% of the positions. Checkmates are possible with the defending king on any square at the edge of the board, but can be forced only from positions with different material or if the defending king is in a corner controlled by the bishop or on a square on the edge next to a corner, but mate adjacent to the corners not controlled by the bishop is only two moves deep, so is not generally encountered unless the defending side plays inaccurately. Although this is classified as one of the four basic or elementary checkmates, it occurs in practice approximately only once in every 6,000 games.
WBoden's Mate is a checkmating pattern in chess characterized by bishops on two criss-crossing diagonals, with possible flight squares for the king being occupied by friendly pieces. Most often the checkmated king has castled queenside, and is mated on c8 or c1. Many variants on the mate are seen, for example a king on e8 checkmated by bishops on g6 and a3, and a king on f1 checkmated by bishops on h3 and b6. Often the mate is immediately preceded by a sacrifice that opens up the diagonal on which the bishop delivers checkmate, and the mate is often a pure mate.
WIn chess, several checkmate patterns occur frequently enough to have acquired specific names in chess commentary. The diagrams that follow show these checkmates with White checkmating Black.
WA helpmate is a type of chess problem in which both sides cooperate in order to achieve the goal of checkmating Black. In a helpmate in n moves, Black moves first, then White, each side moving n times, to culminate in White's nth move checkmating Black. Although the two sides cooperate, all moves must be legal according to the rules of chess.
WIn chess, an ideal mate is a checkmate position that is a special form of model mate. While in a model mate, each piece on the mating player's side participates in the mate, an ideal mate involves all the pieces of the mated player's as well, typically by blocking the mated king's field of movement so that it cannot escape. As in a model mate, an ideal mate also involves the mating pieces attacking the vacant squares around the mated king's exactly once, and not attacking the mated player's other pieces occupying the king's field of movement.
WIn chess, Scholar's Mate is the checkmate achieved by the following moves, or similar:1. e4 e5 2. Bc4 Nc6 3. Qh5 Nf6?? 4. Qxf7#
WIn chess, a smothered mate is a checkmate delivered by a knight in which the mated king is unable to move because he is surrounded by his own pieces. In rare situations, the surrounding pieces may include an opponent's defended piece, which the king can not capture.