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In 1642, the French philosopher and mathematician Blaise Pascal invented the pascaline. It had eight movable dials on wheels and could calulate sums up to eight figures long. It could only perform only addition and subtraction operations just like a abacus.
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Charles Babbage, and English mathematician and physical scientist, designed two calculating machines- the difference engine and the analytical engine. The difference engine could perform complex operations such as squaring numbers automatically. The analytical engine's design included input device, data storage, a control unit that allowed processing instructions in any sequence, and output devices. The designs remained in the blueprint stage.
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The U.S. Census officials needed help in accurately tabulating the census. Herman Hollerith invented a calculating machine that ran on electricity and used punched cards to store data. The machine was immensely successful. Hollerith founded th Tabulating Machine Company, which later became the computer and technology corporation known as IBM.
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Built by IBM and Harvard University under the leadership of Howard Aiken. The punched cards were used to feed data into the machine. The machine was 52 feet long, weighed 50 tons, and had 750,000 parts.
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The University of Pennsylvania built the Electronic Numerical Integrator and Calculator (ENIAC), which contained 18,00 cacuum tubes and weighed some 30 tons.
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The computers that we know today use the design rules given by John von Neumann. It included components such as an arithmetic logic unit, a control unit, memory, and imput/output devices. Also, his computer design makes it possible to store the programming instructions and the data in the same memory space.
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the Universal Automatic Computer (UNIVAC) was built and sold to the U.S. Census Bureau.
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Transistors were replaced by tiny integrated circuits, or "chips." Chips are smaller and cheaper than transistors and can contain thousands of circuits on a single chip. They also give computers tremendous processing speed.
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An entire CPU on a single chip was invented.
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Stephen Wozniak and Steven Jobs designed and built the first Apple computer in their garage.
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IBM introduced its personal computer.
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Clones of the IBM PC made the personal computer even more affordable.
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By the mid-1990s, people from many walks of life were able to afford these personal computers.
