Abacus - calculation toolAbacus was invented in between 1000 BC - 500 BC inMesopotamia and China. An abacus is a calculation tool,constructed as a wooden frame with beads sliding onwires. The first abacus was based on a flat stonecovered with sand or dust. Words and letters weredrawn in the sand, eventually numbers were added andpebbles used to aid calculations.
Antikythera mechanism • The Antikythera mechanism is an ancient mechanical analog computer designed to calculate astronomical positions. • 150-100 BC • The device is about 33 cm (13 in) high, 17 cm (6.7 in) wide, and 9 cm (3.5 in) thick, made of bronze and originally mounted in a wooden frame.
1820s Charles Babbage 1820s Charles Babbage, in England made a "difference engine".
• Yr 1939 - 1946• Dr. Howard Aiken of Harvard completed the basic plans for a sequential, digital, electromechanical computer - Father of all modern computers
ENIAC The Worlds First Electronic Computer 1949 - 1952
Electronic Numeric IntegratedAutomatic Computer - ENIACweighed nearly 30tons and occupied It was the major15,000 square feet instrument for theof floor space. computation of allcontained more than ballistic tables for19,000 vacuum the U.S. Army andtubes which were Air Forceused to perform5,000 additions persecond