In 1973 Gates entered Harvard University. While at Harvard, he and his friend Paul Allen developed software for the first microcomputers. (Microcomputers were smaller and more affordable than earlier computers.) The friends were so successful that Gates left Harvard before graduating. With Allen, he founded Microsoft.
In 1981 the company IBM included Microsoft software in its new personal computers (PCs). Other companies soon began making PCs, and they also depended on Microsoft software.
Microsoft offered the first version of Windows in 1985. Windows was based on earlier programs, such as the system that Apple had created for its Macintosh computers (see Steve Jobs). Information was displayed in multiple tiles, called “windows,” on the computer screen. Soon nearly every PC used Windows. In the 1990s Microsoft began focusing on software related to the Internet.
By the 1990s, Gates had a fortune worth tens of billions of dollars. He decided to give away a large portion of it. In 1994 he and his wife, Melinda, started a foundation that gave money to many projects around the world. For example, the foundation supported efforts to end the disease polio. The couple also funded libraries and scholarships in the United States. In 2008 Gates retired from running Microsoft to work more with his foundation.
