William Henry "Bill" Gates III (born October 28, 1955)[3] is an American business magnate, investor, philanthropist, author, and former CEO and current chairman of Microsoft, the software company he founded with Paul Allen. He is consistently ranked among the world's wealthiest people4 and was the wealthiest overall from 1995 to 2009, excluding 2008, when he was ranked third.[5] During his career at Microsoft, Gates held the positions of CEO and chief software architect, and remains the largest individual shareholder, with more than 8 percent of the common stock.[6] He has also authored or co-authored several books.