The game is played on a line of holes, each of which can hold one peg. A number of blue pegs start out in the leftmost holes, and the same number of red pegs start out in the rightmost holes. The object is to move all the blue pegs to the right and all the red pegs to the left.
There are two ways to move a peg. You can move it to an adjacent empty hole, or you can jump an adjacent peg and move it to the hole on the other side. There are a couple of catches, though. Blue pegs may only be moved right, and red pegs may only be moved left. Furthermore, you must alternate between moving blue pegs and red pegs: i.e., you can't move two blue pegs in a row or move two red pegs in a row. Your first move must be a blue peg.
To move a peg, click on it. You will only be able to click on pegs that are legal to move at any given time. If you reach a point where there are no legal moves, you lose the game. If you manage to get all the red pegs in the leftmost holes and all the blue pegs in the rightmost holes, you win.
Source: The Game Website.