Microsoft finally open sources DOS 1.0 - and it's so much more than the code

Want a blast from the past? Microsoft just open-sourced its very first operating system, offering a rare insight into the ...
Neowin

A quick look back at Microsoft's first computer operating system, Xenix

Long before Windows, and even before MS-DOS, Microsoft sold a Unix-based operating system it called Xenix in 1980. It was the first OS made by the company, but it eventually sold it off in 1987. On ...