Who invented DOS?

On Fri, 4 Mar 2005, Computer Collector Newsletter wrote: HARUMPHH! "DOS" means Disk Operating System. Which includes, but is absolutely NOT limited to MS-DOS/PC-DOS. Only people whose first (and only?) computer was an "AT" would assume that "DOS" means MS-DOS/PC-DOS! The first operating system that I can think of that was NAMED "DOS" was for the IBM 360. Doesn't ANYBODY remember personal computers such as Apple and TRS-80, with prompts such as "DOS READY"? TRS-DOS was written by Randy Cook. Sorry. Who wrote Apple-DOS? MS-DOS/PC-DOS was written by Tim Patterson, but was basically CP/M (by Gary Kildall) MS-DOS/PC-DOS originally had few, if any, similarities to UNIX. But MS-DOS/PC-DOS 2.00 was a rewrite in the hands of UNIX oriented programmers. -- Grumpy Ol' Fred cisin at xenosoft.com