Basic Piece Movement
Each piece has its own style of moving. Moves are made to vacant squares except when cpaturing an opponent's piece. With the exception of the knight, pieces cannot jump over another piece. When a piece is captured, the attacking piece replaces the enemy piece on its square. The capture piece is thus removed from the game and cannot be returned. The King can be put in check but cannot be captured, because once a King is unable to move out of position to be captured, the game is over.
The specific movements of each individual piece are as follows:
- The King piece can move exactly one square horizontally, vertically, or diagonally. Once in every game, each King is allowed to make a special move, known as castling.
- The Rook piece can move any number of vacant squares vertically or horizontally. The Rook is also moved during castling.
- The Bishop piece moves any number of vacant squares in any diagonal direction.
- The Queen piece can move any number of vacant squares diagonally, horizontally, or vertically.
- The Knight piece moves to the nearest square not on the same rank, file, or diagonal. In other words, the Knight moves two squares like the rook and then one square perpendicular to that. Its move is not blocked by other pieces, i.e. it leaps to the new square. The Knight moves in an "L" or "7" shape (or either shape inverted) with two steps one direction, a 90° turn, and one step in the new direction.
- The Pawn pieces have the most complex movement rules:
- A Pawn can move forward one square, if that square is unoccupied. If it has not yet moved, the pawn has the option of moving two squares forward provided both squares in front of the pawn are unoccupied. A pawn cannot move backward.
- Pawns are the only pieces that capture differently from how they move. They can capture an enemy piece on either of the two squares diagonally in front of them but cannot move to these spaces if they are vacant.
The Pawn is also involved in the special move promotion.