MS-DOS (abbreviation for Microsoft Disk Operating System) was a command-line driven operating system family sold as a standalone product in the 1980's and early 1990's, later evolving to be used as a platform on which to run a shell that would later be known as Microsoft Windows. It would later be relegated to a support role in 32-bit editions of Microsoft Windows. It was first developed as 86-DOS by Tim Patterson, with the first version released by Microsoft being marketed as MS-DOS 1.0 in August 1981, which was version 1.14 of 86-DOS.
In 1980, Microsoft then-head Bill Gates (known at the time for his creation of an interpreter for the BASIC computer programming language running on the MITS Altair 8800) was approached by IBM about an operating system for their computer boxes. Paul Allen contacted Tim Patterson of Seattle Computer Products, and acquired the rights to sell his QDOS (Quick and Dirty Operating System) to an unnamed client - IBM - for under $100,000. Deals continued as the product was still under development at Seattle Computer Products; in 1981, Microsoft bought the full rights to the operating system, which they trademarked as MS-DOS.
Legions of games were developed and marketed as being compatible with MS-DOS, and thus the platform is still fairly important, if somewhat ancient. Many of these games can run on FreeDOS, or within DOSBox. The first release of MS-DOS by Microsoft
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