The touch-move rule requires that a player who touches a piece must move it. The rule is used for all serious competitions and applies only to the player who is on move. The player who is not on move may touch pieces, although this is considered bad form; a Tournament Director may penalize a player who is touching pieces to annoy or distract the opponent.
A similar rule requires that a player who releases a piece after making a legal move is considered to have made that move. A player who moves a piece to a square without releasing the piece is entitled to move that piece to a different square.
There is no penalty for a player who touches a piece which has no legal moves. At one time, the rules required the player to move the King, but this rule is obsolete.
A player who touches an opponent's piece is required to capture it, if possible. Castling is considered a King move, and a player should touch the King before the Rook.
