Bill Gates is cochair of the Bill & Melinda Gates Foundation. In 1975, he founded Microsoft with Paul Allen. A geek icon, tech visionary and business trailblazer, Gates led the company to become the worldwide leader in business and personal software and services.

In 2008, Gates transitioned from his day-to-day role with Microsoft to focus full-time on his foundation’s work to expand opportunity to the world’s most disadvantaged people. Along with cochair Melinda Gates, he leads the foundation’s strategic development and sets the overall direction of the organization. Holding that all lives have equal value no matter where they're being lived, the foundation has donated staggering sums to HIV/AIDS programs, libraries, agriculture research and disaster relief -- and offered vital guidance and creative funding to programs in global health and education.

Together with Warren Buffett, the Gateses founded the Giving Pledge, an effort to encourage the wealthiest families and individuals to publicly commit more than half their wealth to philanthropic causes and charitable organizations either during their lifetime or in their will. In 2015, Gates created the Breakthrough Energy Coalition, a group of individuals and entities committed to clean energy innovation, followed by Breakthrough Energy Ventures, an investor-led fund that provides patient capital to support cutting-edge clean energy companies.

Follow Gates's ongoing thinking on his personal website, The Gates Notes, and read a collection of Bill and Melinda Gates's annual letters, where they take stock of the Gates Foundation and the world.