The history of computers initially began with humans using tools such as pebbles and notches in sticks to count objects. The human aspect of computers is that they wanted a way to perform calculations, which included adding and multiplying multiple numbers. The hand calculator was one of the early stages of the computer's history, even though humans had to perform the calculations. The hand computer had the abacus, which was a frame that held beads mounted on rods. This technology was used in Rome, Greece, India, China and Japan. In 1623, Wilhem Schicard, a university professor, developed the first mechanical calculator. It worked on its own, even if a human had to enter the numbers. Later, a mathematician named Charles Babbage designed a general-purpose calculator called the analytical engine. The concept of this computer was to modernize itself with memory, processor and an output device. The information was on punched cards and allowed the user to define and enter programs. In the 1890s, metal rods were used to read ballots or data was introduced by Herman Hollerith, a statistician, at the US Census Bureau. Hollerith was the first American to use that device. He later founded the Tabulation Machine Company. Tabulating numbers soon became the way to sort and count cards. Tabulation also became the way of doing business for many companies. In 1936 Konrad Zuse designed the Z1 computer, which was the first freely programmable computer. In 1942, John Atanasoff and Clifford Berry founded ABC Computer, the first in the computer industry, although it wasn't always as easy as ABC. In 1944, Howard Aiken and Grace Hopper invented the Harvard Mark 1 computer. In 1946 John Pr...... middle of paper ......appeared in 1971 on minicomputers, which was one of the programs for electronic design automation . Eventually, the microprocessor led to the development of the microcomputer, a small, low-cost computer that could be owned by individuals and small businesses. Therefore, microcomputers became obsolete in the 1980s. Today the personal computer is used by millions of individuals. They are also used in business and academia. Microsoft, founded by Bill Gates and Paul Allen, is one of the largest industries in the world and computers are owned by most American families.Works CitedCIS 111, Parson, Oja, Beskeen, Cram, Duffy, Fredrichson, Reding, Basic PC Literacy, First edition 2011History of Modern Computing: Paul E Ceruzzi Second edition MIT press Cambridge, Massachusetts, 1998http://en.wikipedia.org/wiki/History_of_computing_hardware