When an adverse piece is moved so that it could capture the King on the next move, due notice must be given to the threatened King by announcing “Check,” and the player must immediately move his King out of check, interpose a piece or a Pawn, or capture the piece that gives the check. If he cannot do one of these three things he is mated, and loses the game. A very simple example of a mate is given in Diagram No. 8.
No. 8.
The white Rook has just been moved down to the edge of the board, giving “check.” As the black King can move only one square at a time, he cannot get out of check by moving, because the only squares to which he could go would still leave him in check from the Rook. Neither the Knight nor the Bishop can interpose to shut out the Rook’s attack; neither of those pieces can capture the Rook; and the Pawns cannot move backward; so the black King is mated, and White wins the game.
A mate may take place in the middle of the board, as shown in Diagram No. 9.
No. 9.
If the black Queen moves diagonally four squares, placing herself in front of the white King, and on the same horizontal file as the black Rook, it will be check-mate, because the white King cannot get out of one check into another by taking the Queen, which is protected by the Rook. For the same reason he cannot move, as the only squares open to him would leave him in check from the Queen, or move him into check from the black King.
Stalemate. If the King is not in check, but cannot move without going into check, and there is no other piece for the player to move, it is called a stale-mate, and the game is drawn. In Diagram No. 10, for instance,