The time line of the progression of computers and computer technology. * 500bc the Abacus was first recorded to be used in China. The Abacus was not an electronic machine, but a hand held tool that could temporarily store and work with large numbers. * 1820 Charles Babbage designs the first mechanical analytical engine, but did not have the technology and resources available to construct the Babbage Differential engine until 1991. When constructed by a team from the science museum in London, they used techniques that would have been available in Babbage time, to prove that the design would have worked in his time. It took a total of six years to construct but was successfully done and proved his Babbage design was sound and could have been implemented in his own time. * 1890 Hollerith Machine was successfully constructed by Herman Hollerith to assist with the US Census * 1933 Telex was conceived during at the time Germanys Third Reich, it allowed input of information to be delivered worldwide on paper as an output. * 1937-1942 John V. Atanasoff and Clifford Berry created the first digital electronic computer known as the Atansasoff-Berry Computer ABC for short. It was the first to use modern digital switching techniques and vacuum tubes as switches, and it introduced the concepts of binary arithmetic and logic circuits. * 1943 during WWII Military needs leads Tommy Flowers in completing a secret British codebreaking computer called Colossus and was named appropriately so due to its size and used vacuum tubes and 1,500 of them. * 1946 Hitler is defeated, and ENIAC was constructed at the Moore School of Electrical Engineering at the University of Pennsylvania by John P. Eckert, John W. Mauchly and their associates. It operated on a 10-diget numbers and could multiply numbers at the rate of 300 products per second. It was 1000 times faster