Bill Gates (William Henry Gates ) was born in octobur 28,1955 in Seattle, Washington. His family was upper middle class. His father was a prominent lawyer. At age of 13 he enrolled in Lakeside school. Gates took an interest in programming the GE system in basic. He wrote his first computer program on this machine an implementation of tic-tac-toe that allowed users to play games against the computer. After his administrators became aware of his programming abilities, Gates wrote the school's computer program to schedule studentsin classes.Gates graduated from Lakeside School in 1973. In 1974 Gates and Allen saw the release of MITS Altair 8800 based on the 8080 CPU. And Gates and Allen saw this as the opportunity to start their own computer software company and on November 26,1976 , the trade name "Microsoft" was registered with the office of the Secretary of the New Mexico.In 1980,IBM approached Microsoft to write the basic interpreter for personal computer.Gates processed 86-DOS for operating system and delivered it to IBM as PC-dos for aone time fee $50,000.On November 20,1985 he launched its retail version of Microsoft Windows.