Microsoft becomes incorporated and Bill Gates becomes President

Gates oversaw Microsoft's company restructuring on June 25, 1981, which re-incorporated the company in Washington and made Gates President of Microsoft and the Chairman of the Board.[26] Microsoft launched its first retail version of Microsoft Windows on November 20, 1985, and in August, the company struck a deal with IBM to develop a separate operating system called OS/2. Although the two companies successfully developed the first version of the new system, mounting creative differences undermined the partnership. Gates distributed an internal memo on May 16, 1991, announcing that the OS/2 partnership was over and Microsoft would shift its efforts to the Windows NT kernel development.

1981: Microsoft incorporates and buys the rights to the operating system “DOS” from Seattle Computer Products. The system is modified and renamed MS-DOS, and the company licenses it to IBM for the company’s new personal computer.

June 25, 1981

Microsoft reorganizes into a privately held corporation with Bill Gates as president and chairman of the board and Paul Allen as executive vice president. Microsoft becomes Microsoft, Inc., an incorporated business in the state of Washington.

From Microsoft's founding in 1975 until 2006, Gates had primary responsibility for the company's product strategy. He aggressively broadened the company's range of products, and wherever Microsoft achieved a dominant position he vigorously defended it.
As an executive, Gates met regularly with Microsoft's senior managers and program managers. Firsthand accounts of these meetings describe him as verbally combative, berating managers for perceived holes in their business strategies or proposals that placed the company's long-term interests at risk.[34][35] He often interrupted presentations with such comments as, "That's the stupidest thing I've ever heard!"[36] and, "Why don't you just give up your options and join the Peace Corps?"[37] The target of his outburst then had to defend the proposal in detail until, hopefully, Gates was fully convinced.[36] When subordinates appeared to be procrastinating, he was known to remark sarcastically, "I'll do it over the weekend."[3][38][39]
Gates's role at Microsoft for most of its history was primarily a management and executive role. However, he was an active software developer in the early years, particularly on the company's programming language products. He has not officially been on a development team since working on the TRS-80 Model 100 line, but wrote code as late as 1989 that shipped in the company's products.[38] On June 15, 2006, Gates announced that he would transition out of his day-to-day role over the next two years to dedicate more time to philanthropy. He divided his responsibilities between two successors, placing Ray Ozzie in charge of day-to-day management and Craig Mundie in charge of long-term product strategy