What Elmer A. Sperry invented?

The yo-yo was first used by hunters as weapons. They were wooden disks on strings. In the 1920s, a man from the U.S. named Donald Duncan made the yo-yo into a toy after he visited the Philippines.

Know as the Father of Computing. He began his 'Analytical Engine' in 1833. The first computer, although he never completed it.

After the Stock Market crash, a buying and selling game created by Charles Darrow came to be. The first games were hand drawn on linoleum with streets from Atlantic City, N.J. as the property. He took the game to the Parker Brothers company, and Monopply was brought out for Christmas 1934. Everyone wanted to buy the games after Christmas, and Monopoly became a big success.

Christopher Cockerell invented the hovercraft in 1956. His early experiments with the idea involved a cat food tin, a coffee tin and an industrial blower.

The first toothbrush was made out of a bone and small brush, by jail prisoner William Addis of England.

Bette's other claim to fame was being the mother of Michael Nesmith of the Monkees.

Alexander Graham Bell's notebook entry of 10 March 1876 describes his successful experiment with the telephone. Speaking through the instrument to his assistant, Thomas A. Watson, in the next room, Bell utters these famous first words, "Mr. Watson -- come here -- I want to see you".

SPICE (Simulation Program with Integrated Circuit Emphasis) was introduced in May 1972 by the University of Berkeley, California.