There are standard, trackball, optical, and USB mice. Outside of the mice are either two or three buttons. The outside buttons are used to click on icons or links, while a three-button mouse has the capability of double-clicking. "When we move the mouse, a ball rolls in
the direction of the movement. This moves a roller which moves the chopper gear. These components are housed inside a cavity underneath the mouse. The mouse ball is the main component inside and allows the user to move the mouse cursor on the screen. The cursor would be motionless without the ball. And the ball uses two Choppers and Gears to transmit its movement to the computer" (Cooper, 2009, pg. 1). In an optical or USB mouse, the ball is replaced with a laser beam. The trackball mouse is the same as the standard mouse, except for the fact that the ball is located on the top of the device and operated with a finger. Also significant is the fact that standard and trackball mice have a cord, while USB mice are definitely cordless, including many optical mice (Cooper, 2009).
There are several manufacturing processes that are employed simultaneously in order to produce a computer mouse. Steps one through three encompass these tasks, while steps four through seven marks the point where the mouse is brought together for final assembly: