Microsoft Disk Operating System

(M-S-doss)

A version of DOS written specific to Microsoft. Versions included PC-DOS for IBM systems. MS-DOS is basically an 8088-based clone of CP/M. It's first version was put together by Tim Paterson in about six weeks (sources say he's regretted it ever since). As developed, MS-DOS ran one program at a time and was limited to one megabyte of memory; 640KB of that being available to programs. DOS add-ons greatly expanded its life and gave it an ability to switch between multiple programs in a single session. As a standalong operating system, MS-DOS went through six major versions after which it was incorporated into Windows and served for some time hidden under Windows. Some MS-DOS functions continue to be built into the Windows operating system for backward compatibility purposes.

A compatible DOS with extended features called DR-DOS was developed by Digital Research but despite its advantages were too little, too late (it is still marketed by Caldera, Inc. as DR-OpenDOS).

MS-DOS has not always been popular with some advanced computer users. There you might hear it talked of as MS-DOG, Messy-DOS, mess-dross, mess-loss, or mush-dos (or other not so nice terms). Domestos is a name sometimes used in the UK and Ireland (this is a brand of toilet cleaner).

More Information

• MS-DOS Secrets
• DOS Command Index
• MS-DOS Help