Microsoft finally open sources DOS 1.0 OS (first released 1981) - and it's so much more than the code

Good news! Yes, I remember the DOS operating system, the predecessor of Windows. I used it way back then on my IBM PC, which was a gift of my late mother Irma Bingel.

"Before "Micro Soft" became Microsoft, Bill Gates wrote BASIC interpreters. Microsoft's first shipping operating system was a Unix distro called Xenix.

Then, in 1980, Microsoft got its shot at the big time: IBM needed an operating system for its planned IBM PC and asked Gates if he could deliver one. You betcha! The rest is history. ..."

Microsoft finally open sources DOS 1.0 - and it's so much more than the code | ZDNET "Want a blast from the past? Microsoft just open-sourced its very first operating system, offering a rare insight into the PC's earliest days."