ZDNet

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

PC-DOS 1.00 would lead to Microsoft becoming computing's top dog Microsoft continues to embrace open source. The source code and annotations provide insight into the operating system's earliest days.
Ars Technica

Microsoft open-sources “the earliest DOS source code discovered to date”

I always thought it stood for Disk Operating System. I was fucking around with it back in the early 80's after I got out of the Navy, and had taken some BASIC courses. I wrote a program to find out ...
TechSpot

Microsoft releases the earliest DOS source code ever discovered as open source

Editor's take: Microsoft continues to tightly control the release of some of its most important pieces of legacy software. While enthusiasts and programmers are eager to see newer versions of MS-DOS ...

Microsoft open-sources “the earliest DOS source code discovered to date”

Several times in the last couple of decades, Microsoft has released source code for the original MS-DOS operating system that kicked off its decades-long dominance of consumer PCs. This week, the ...