Its movement in nowadays chess is still the same as it was about one and a half millennium ago. In Chaturanga, it was called Ratha , a Sanskrit word meaning chariot . Hence the representation of the piece as a tower or castle. The rook moves an arbitrary number of squares in horizontal or vertical direction, but may not jump over occupied squares.
Rooks take in the same way as they move without taking.
Written by Hans Bodlaender. Diagram by Ben Good.