Castling is a special move in chess that uses both a rook and the king. In castling, the king is moved two squares toward the rook, and the rook moves past the king to the square right next to where the king has moved. Castling takes one move, and is the only way for a player to move two of his own pieces on the same move. Castling can be done on either side of the board.
Rules for castling [change]
Castling is only possible if each of the following things are true:
- Neither the king nor the rook being used to castle have moved in the game.
- The king is not in check, and is not moving into check or through check. (It is okay if the rook is being attacked, though).
- There are no pieces between the king and the rook.
Why castling is often a good idea [change]
Good players castle in most of their games. It is normally a good idea because it often moves the king into a safer place. The middle of the board is normally not a very safe place for the king to be early in the game. It also makes it easier to get the rook into the game.