From Zillions of Games
"Pieces move diagonally but capture orthogonally. This is so as to combine the forced progression of diagonal checkers with the richness of the orthogonal game.
Object: Capture all your opponent's pieces ("Checkers" or "Kings") by jumping over them, or stalemate the opponent so he has no moves.
Checkers can move diagonally forward, by sliding to an adjacent empty square or by jumping either left, right, or forward over an enemy piece to a vacant square on the other side. Jumping over a piece captures it, but you may not jump diagonally. Capturing is mandatory, and you must keep jumping and capturing as long as it is possible, taking the maximum number of pieces.
The King is a long range piece and can slide diagonally in any direction or jump left, right, up or down over any opponent piece to any free square. When your Checker stops on the other end of the board, it becomes a King and can then also move backwards. If it merely visits a promotion square during a series capture moves, then it does not promote."