Timeline

• 1642: French scientist Blaise Pascal invents first machine that can solve addition and subtraction equations.

• 1832: English mathematician Charles Babbage adds punch cards that give the computer memory.

• 1939: American mathematician John V. Atanasoff develops the first computer powered by electricity.

• 1960s: Companies and the government start making more and more use of big computers.

• 1975: The development of the silicon chip made smaller computers possible. Bill Gates and Paul Allen start Microsoft.

• 1976: Steve Jobs and Steve Wozniak start Apple Computers.

• 1977: Apple begins selling its first popular computer, the Apple II.

• 1981: IBM releases the popular 5150, using Microsoft's operating system.

• 1984: Apple introduces its popular Macintosh computer.

• 1991: The World Wide Web begins and computer sales increase.