Computer mouse

What is the computer mouse?
A computer mouse is a coordinate device for controlling the cursor and giving various commands to a computer. The cursor is controlled by moving the mouse over the surface of the table or a mouse pad.

First computer mouse
It was made of wood and was the first input device that fit into the user's hand. Under the case there were two metal disks-wheels, a diagram. The button was only one, and the wire went under the wrist of the person holding the device.

Upgrade
In 1968, in a computer conference at San Francisco, D. Engelbart presented the improved first computer mice. They had three buttons, in addition to them the keyboard was equipped with a device for the left hand.
In 1972, Bill English replaced the wheels with a trackball, which made it possible to recognize mouse movement in any direction.