DOS

ALSO CALLED: Disk Operating System
DEFINITION: DOS (Disk Operating System) was the first widely-installed operating system for personal computers. (Earlier, the same name had been used for an IBM operating system for a line of business computers.)The first personal computer version of DOS, called PC-DOS, was developed for IBM by Bill Gates and his new Microsoft Corporation. He retained the rights to market a Microsoft version, called MS-DOS.  … 
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DOS DEFINITION (continued): …  PC-DOS and MS-DOS are almost identical and most users have referred to either of them as just "DOS." DOS was (and still is) a non-graphical line-oriented command- or menu-driven operating system, with a relatively simple interface but not overly "friendly" user interface. Its prompt to enter a command looks like this:C:>The first Microsoft Windows operating system was really an application that ran on top of the MS-DOS operating system. Today, Windows operating systems continue to support DOS (or a DOS-like user interface) for special purposes by emulating the operating system. In the 1970s … 
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