First Microsoft Os -

It was the first time software transformed a hobbyist's circuit board into a usable computer. It established Microsoft’s core philosophy:

When AT&T started directly marketing UNIX in the 1980s, Microsoft decided not to compete with them. They gradually transferred Xenix ownership to the Santa Cruz Operation (SCO) by the late 1980s. 2. The Catalyst: Project Chess and MS-DOS (1981) first microsoft os