Sliding piece

A sliding piece travels along a line until it reaches the edge of the board or another piece. Bishops slide on diagonals, rooks on ranks and files, and queens combine both kinds of line.

• A friendly piece blocks the path and cannot be crossed or captured.
• An enemy piece may be captured if it is the first obstacle, but the move ends on that square.
• Squares beyond any obstacle are unavailable to that sliding piece.

'Sliding' describes a movement mechanism, not piece value. A king also follows lines, but only for one square and is not normally classified as a slider. A knight is not one because it jumps. A promoted piece can be a slider when a pawn becomes a queen, rook, or bishop.

Potential distance does not make every destination a legal move. The path must be clear, and the move must satisfy every other rule, including the safety of the moving side's king.