Draughts or checkers is a group of abstract strategy board games between two players which involve diagonal moves of uniform pieces and mandatory captures by jumping over the enemy's pieces. Draughts is played by two people, on opposite sides of a playing board, alternating moves. One player has dark pieces, and the other has light pieces. The player with the dark pieces makes the first move unless stated otherwise. Pieces move diagonally and pieces of the opponent are captured by jumping over them. The playable surface consists only of the dark squares. A piece may only move into an unoccupied square. Capturing is mandatory. A piece that is captured is removed from the board. In all variants, the player who has no pieces left or cannot move anymore has lost the game unless otherwise stated.