The Microsoft Founder is Bill GATES, a 5-letter answer to the crossword. GATES is an American business magnate, investor, author, philanthropist, and humanitarian. He is best known as the co-founder of Microsoft Corporation, the world's largest personal-computer software company. GATES has held the position of chairman, chief executive officer, president and chief software architect, and was the largest individual shareholder until May 2014. He has also authored or co-authored several books. GATES is one of the best-known entrepreneurs of the personal computer revolution.