Click and hold the mouse button to set your starting position and angle. With the mouse button down, you can control the spin on the ball. Release to throw.
Standard bowling scoring is used: One point per pin knocked down for each ball. Knocking down all ten pins in one frame (with two throws) is a spare, and gets you a bonus of the next throw; Knocking down all ten pins in your first throw is a strike, and gets you a bonus of the next two throws. Throw a spare or a strike in the tenth frame to get an extra ball.