You have to clear the board by jumping one peg over another into an empty spot. This removes the peg you jumped over from the board. Just click on a peg and if there's a valid -- horizontal or vertical -- move available, the peg will "jump". If there's more then one valid move available, you'll have to choose a destination. To win you have to end up with only one peg. The best solution has this peg in the center.