Microsoft founders Bill Gates and Paul Allen were all smiles in 1983 just after delivering MS Dos for the Tandy laptop and signing a contract to write MS-DOS for IBM.

Photo: Doug Wilson/Corbis __1975: __ Bill Gates and Paul Allen create a partnership called Micro-soft. It will grow into one of the largest U.S. corporations and place them among the world's richest people.

Gates and Allen had been buddies and fellow Basic programmers at Lakeside School in Seattle. Allen graduated before Gates and enrolled at Washington State University.11 They built a computer based on an Intel 8008 chip and used it to analyze traffic data for the Washington state highway department, doing business as Traf-O-Data.

Allen went to work for Honeywell in Boston, and Gates enrolled at Harvard University in nearby Cambridge. News in late 1974 of the first personal computer kit, the Altair 8800, excited them, but they knew they could improve its performance with Basic.

Allen spoke to Ed Roberts, president of Altair manufacturer MITS (Micro Instrumentation and Telemetry Systems), and sold him on the idea. Gates and Allen worked night and day to complete the first microcomputer Basic. Allen moved to Albuquerque, New Mexico, in January 1975 to become director of software for MITS. Gates dropped out of his sophomore year at Harvard and joined Allen in Albuquerque.

Allen was 22; Gates was 19. Altair Basic was functioning by March. The "Micro-soft" partnership was sealed in April, but wouldn't get its name for a few more months.

The fledgling company also created versions of Basic for the hot-selling Apple II and Radio Shack's TRS-80.

Microsoft moved from Albuquerque to Bellevue, Washington, in 1979. It incorporated in 1981, a few weeks before IBM introduced its personal computer with Microsoft's 16-bit operating system, MS-DOS 1.0.

The thriving young company moved again in 1986, this time to a new corporate campus in Redmond, Washington. Microsoft stock went public in March 1986. Adjusting for splits, a share of that stock is worth almost 280 times its original value today (or more than 140 times, even accounting for inflation).

Source: Various

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