Apple DOS

Apple DOS is an operating system designed for the Apple II line of computers.

Versions
It is the very first OS released by Apple, Inc., or Apple Computer. Starting with Apple DOS 2.8, and ending with Apple DOS 3.3, the process went four years, from 1977 (Apple DOS 2.8), to 1978 (Apple DOS 3.0, Apple DOS 3.1), to 1979 (Apple DOS 3.2), to 1980 (Apple DOS 3.3).