Thirty years ago, on July 27 1981, Microsoft bought the rights for QDOS (Quick and Dirty Operating System) from Seattle Computer Products (SCP) for $25,000. QDOS, otherwise known as 86-DOS, was designed by SCP to run on the Intel 8086 processor, and was originally thrown together in just two months for a 0.1 release in 1980.
Meanwhile, IBM had planned on powering its upcoming Personal Computer with CP/M-86, which had been the standard OS for Intel 8086 and 8080 architectures at the time, but a deal could not be struck with CP/M’s developer, Digital Research. IBM then approached Microsoft, which already had a few years of experience under its belt with M-DOS, BASIC, and other important tools — and as you can probably tell from the landscape of the computer world today, the IBM/Microsoft partnership worked out rather well indeed.
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