Chinook is a pure movement game played on 4x8 checkers board.  The red player's pieces are positioned on the odd squares, and the blue players pieces are positioned on the even squares.  Red's pieces move up the board by advancing diagonally to an empty square or by jumping over its own pieces.  Single jumps only.  The blue player's pieces move down the board by advancing diagonally to an empty square or by jumping over its own pieces.  Single jumps only.  Note that the board wraps around both horizontally and vertically, e.g. it is possible to move from the righthand side of the board to the left and vice versa.  Each player's score is based on the number of pieces in their "target" positions (the three rows across from their starting positions).  The game ends whenever one player has all pieces in their target positions or on step 41, whichever comes first.