The message DOS displays when it is ready to accept input on the command line. See cmd abc's. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.
MS-DOS 4.00 is quite an interesting version of this command-line-driven OS ... Enthusiasts with serviceable old hardware like an original IBM PC XT, or a newer Pentium system, can run / install ...
In the world of PC graphics, the early standards followed the various video cards of the day. There was MDA, familiar through the original text-based DOS prompt, CGA, then EGA, and the non-IBM ...