Swap the two colors. Play this game which dates back to Victorian Times.
This is an ancient puzzle game which dates back to Victorian Times. In this game you should swap the two colors as using as few steps as possible. A peg can move into its adjacent blank space or jump over another peg into the empty space.
A context menu should be shown when right-clicking or, on touch devices, long-pressing in the game. This menu especially allows to play in full screen and control the volume.