William Henry Gates III (born October 28, 1955) is an American businessman and philanthropist, primarily known for co-founding the software giant Microsoft in 1975 with his childhood friend Paul Allen. A pioneer of the microcomputer revolution, Gates led Microsoft as CEO and chairman, becoming the world's youngest billionaire in 1987 and the wealthiest person for 18 out of 24 years between 1995 and 2017.
He gradually transitioned from his full-time role at Microsoft, stepping down as CEO in 2000 and chairman in 2014, to dedicate more time to philanthropy. Through the Bill & Melinda Gates Foundation, which he co-chaired until 2024, he has focused immense resources on global health, education, and poverty alleviation, famously working to eradicate diseases like polio and malaria.
Still serving as a technology adviser to Microsoft, Gates also co-founded the Giving Pledge in 2010 with Warren Buffett, encouraging billionaires to donate most of their wealth to charity. For his significant impact, he has received numerous honors, including a Presidential Medal of Freedom in 2016.