This is the game known as "Towers of Hanoi". Your task is to move the tower from the start position (left) to the end position (right). The tower consists of several disks which lay on each other. You can move only a disk which is on the top of a tower and lay this either on an empty position or on a disk which has a greater radius.
You can use the mouse or the keys from 1 to 3 for this game.

Move the small disk to the middle, the large one to the right and then ...