In general, rooks are stronger than bishops or knights (which are called minor pieces) and are considered greater in value than either of those pieces by nearly two pawns but less valuable than two minor pieces. Two rooks are generally considered to be worth slightly more than a queen. Winning a rook for a bishop or knight is referred to as winning the exchange. Rooks and queens are called heavy pieces or major pieces, as opposed to bishops and knights, the minor pieces.

The rook also participates, with the king, in a special move called castling.

The rook moves horizontally or vertically, through any number of unoccupied squares.