To get the answer, just put a decimal point in the number "50"—my first Microsoft product was MS-DOS 5.0.

and running MS-DOS, Microsoft's character-based operating system on which we ran everything from word processors and spreadsheets to basic games and bulletin board discussion systems. There was ...

The art of writing has become a cluttered one to follow, typically these days through a graphical word processor ... There’s MS Word 5.5 for DOS, in the public domain since it was released ...