When a king is under attack from an opponent's piece it is in "check".
A player must then find a way out of "check", so that his/her king is not under attack.
Three ways this can be done:
1) Capture the piece that is attacking the king, either by the king or by another piece. This
is usually the best option, since it eliminates the direct threat.
2) Block the attack - by placing one's own piece in between the king and the attacking piece.
3) Move out of check - move the king one square in any direction, that is not under attack.
See examples of "
check!".
Note: If a king can escape "check", the player is still alive. If a king cannot escape,
then it is considered a "checkmate" and the game is over.
