rook(chess)

The rook (/rʊk/; ♖, ♜) is a piece in the game of chess resembling a castle. Formerly the piece (from Persian رخ rokh/rukh, meaning chariot) was alternatively called the tower, marquess, rector, and comes (count or earl) (Sunnucks 1970). The term castle is considered to be informal, incorrect, or old-fashioned.[1][2]

Each player starts the game with two rooks, one on each of the corner squares on their own side of the board.The white rooks start on squares a1 and h1, while the black rooks start on a8 and h8. The rook moves horizontally or vertically, through any number of unoccupied squares (see diagram). The rook cannot jump over pieces. As with captures by other pieces, the rook captures by occupying the square on which the enemy piece sits. The rook also participates, with the king, in a special move called castling.The rook is worth about 5 pawns. 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 by approximately a pawn. Two rooks are generally considered to be worth slightly more than a queen (see chess piece relative value). [3] 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 piece

Rooks are most powerful towards the end of a game (i.e., the endgame), when they can move unobstructed by pawns and control large numbers of squares. They are somewhat clumsy at restraining enemy pawns from advancing towards promotion, unless they can occupy the file behind the advancing pawn. As well, a rook best supports a friendly pawn towards promotion from behind it on the same file (see Tarrasch rule).

In a position with a rook and one or two minor pieces versus two rooks, generally in addition to pawns, and possibly other pieces – Lev Alburt advises that the player with the single rook should avoid exchanging the rook for one of his opponent's rooks (Alburt 2009:44).

The rook is a very powerful piece to deliver checkmate. Below are a few examples of rook checkmates that are easy to force.