Microsoft cofounder Bill Gates. Ramin Talaie/Getty Images Before Microsoft had Office, before it had Windows, it had an operating system called MS DOS.

MS DOS was a command-line operating system, meaning you had to memorize a lot of commands and type them into the computer to get it to do things like show you a list of files.

And for the past 36 years, every version of Windows still had a way for people to get to this MS DOS command prompt to find and manipulate files, for those needing to do things with their PCs in that old-school way. Until now, reports Computerworld's Steven J. Vaughan-Nichols.

Last month, Microsoft quietly retired the MS DOS prompt in its latest version of Windows 10 released to Microsoft's developer community (known as Windows Insiders). It is being replaced by a technology called PowerShell. That's a Microsoft technology for writing scripts that just celebrated its 10-year anniversary, Microsoft announced in a blog post.

Ever sensitive to the fact that Windows users, especially programmers, are very particular, it is possible to tell Windows that you don't want the classic MS DOS prompt to go away in favor of PowerShell. So it's not completely dead, yet. But short of that, it's good-by to the face of MS DOS.

The making of Bill Gates

The history of MS DOS is part legend, part myth, but either way, it is responsible for Bill Gate's fortune, as well as that of Microsoft co-founder Paul Allen.

MS DOS Microsoft The story goes: IBM was building a new device, a personal computer, using a fast new chip and it needed an operating system.

It went to the guy who was famous at the time for building operating systems for small computers. Legend has it, he wasn't home because he was a pilot and out flying, so the meeting never happened. Another version says he did meet with IBM but couldn't agree on price.

Meanwhile, IBM also decided not to write all the software for the new device itself and came to a tiny company called Microsoft to partner on a language called BASIC. Microsoft had become known for this language.

In talking to IBM, Bill Gates heard of IBM's predicament for an operating system so he went out and bought one, and hired the guy that created it to turn it into MS DOS. It was one that competed with the pilot's operating system. Legend has it, he paid $75,000, offered it to IBM for $50,000 with the stipulation that Microsoft was allowed to license it to other PC makers, too.

And with that Microsoft's empire was born. The business model of licensing the same operating system to many PC makers took off, and the PC industry flourished. Flash forward a couple of decades and Bill Gates became the richest guy in the world.