Mice originally used two separate wheels to track movement across a surface one in the X-dimension, and one in the Y. The first public demonstration of a mouse controlling a computer system was in 1968.
This motion is typically translated into the motion of a pointer on a display, which allows a smooth control of the graphical user interface of a computer. A computer mouse (plural mice, sometimes mouses) is a hand-held pointing device that detects two-dimensional motion relative to a surface.
