Link — 1st Mouse

: Instead of a trackball or an optical sensor, it used two metal wheels positioned perpendicularly to each other. One wheel tracked horizontal movement, while the other tracked vertical movement.

| Development | Year | Derived from first mouse | |-------------|------|--------------------------| | Xerox ball mouse | 1972 | Wheel mechanism replaced by ball | | Apple Lisa/Macintosh mouse | 1983/1984 | Buttons increased to two; optical encoder disk | | Optical mouse (first commercial) | 1999 | Relative displacement principle | | Touchpad (indirect derivative) | 1990s | Maintains relative positioning without moving parts | 1st mouse