t an employee event held today, Bill Gates said farewell to the company he co-founded back in 1975. Gates will move from one giant to another, as he will turn his focus on the Bill & Melinda Gates Foundation, which is the world's largest charity. Reports say Gates and Microsoft Chief Executive Steve Ballmer delivered speeches to the assembled employees and press, each choking back tears as they spoke.

"There won't be a day in my life when I won't be thinking about Microsoft, the great things that we're doing and wanting to help," Gates told the crowds. The 52-year-old self-professed nerd will now work on finding vaccines and helping to finance projects in developing countries as part of the Foundation headed up by him and his wife. He will remain Microsoft's chairman and contribute to special technology projects.

Under Gates' oversight, Microsoft went from creating the operating system for IBM PCs, MS-DOS, before developing the first graphical user interface of that program, Windows, in 1985. More recently, the company came out with its Xbox gaming console in 2001 to fight Sony's entry into the market at the time, the PlayStation 2. Apple's iPod popularity led to the software giant to develop the Zune series of portable music and multimedia players in 2006.

Gates' various roles at Microsoft will be replaced by three individuals. The chief software architect is now Ray Ozzie, Craig Mundie will act as chief research and strategy office while Steve Ballmer, Gates' long-time friend and Harvard classmate, will assume chief executive officer duties.