When a player moves a piece to a position where the opponent's king is directly threatened, that king is said to be in check. The player putting the opponent's king in check must announce, "Check." The player with a king in check must respond by escaping check. There are three ways to escape check:
• capture the checking piece
• block the checking piece
• move the king out of check
In the illustration below, the black king is in check by the white queen. White has no piece to capture the checking queen. White can block check with the bishop at c8, the knight at b8 or the queen, or White can escape check by moving the king to e8, g7 or g6.