Bill Gates was born on October 28, 1955. He grew up in Seattle, Washington. He was a very clever boy. His favorite subjects at school were science and math. When he was 13 years old, Bill started to play with computers. At that time, computers were very large. Once he was very interested in a very old computer. He and some of his friends spent lots of time doing things with it. In the end, they worked out a software program (软件程序) with the old computer. Bill sold it for $4,200 when he was only 17.
In 1973, Bill went to Harvard University. In his third year, he left Harvard to work for a company called Microsoft. Bill began his company in 1975 with his friend Paul Allen. They thought the computer would come into every office and every home soon. So they began developing (发展) the software for personal computers. They improved the software to make it easier for people to use computers.