Early Tools and Machines Already in early cultures men aimed at the expansion of their physical power in order to facilitate work processes. In prehistoric times first tools made of stone were developed and some thousand years later followed by the invention of simple mechanical devices and machines such as the wheel, the lever and the pulley. Next came the construction of powered machines. Waterwheels, windmills and simple steam-driven devices did no longer require human strength to be operated. In China for example trip-hammers powered by flowing water and waterwheels were already used some 2,000 years ago. Besides tools and machines, which helped to extend men's physical power also devices to support mental faculties, especially in the field of mathematics, were invented. As soon as 3000 BC the abacus was developed in Babylonia. By using a system of sliding beads arranged on a rack early merchants could make computations, which helped them keep track of their trading transactions. Also, early "industrial-robot devices" were developed as soon as 250 BC. The clepsydra, or water clock, which improved upon the hourglass by employing a siphon principle to automatically recycle itself, was constructed by a Greek inventor and physicist, Ctesibius of Alexandria.

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The 19th Century: First Programmable Computing Devices Until the 19th century "early computers", probably better described as calculating machines, were basically mechanical devices and operated by hand. Early calculators like the abacus worked with a system of sliding beads arranged on a rack and the centerpiece of Leibniz's multiplier was a stepped-drum gear design. Therefore Charles Babbage's proposal of the Difference Engine (1822), which would have (it was never completed) a stored program and should perform calculations and print the results automatically, was a major breakthrough, as it for the first time suggested the automation of computers. The construction of the Difference Engine, which should perform differential equations, was inspired by Babbage's idea to apply the ability of machines to the needs of mathematics. Machines, he noted, were best at performing tasks repeatedly without mistakes, while mathematics often required the simple repetition of steps. After working on the Difference Engine for ten years Babbage was inspired to build another machine, which he called Analytical Engine. Its invention was a major step towards the design of modern computers, as it was conceived the first general-purpose computer. Instrumental to the machine's design was his assistant, Augusta Ada King, Countess of Lovelace, the first female computer programmer. The second major breakthrough in the design of computing machines in the 19th century may be attributed to the American inventor Herman Hollerith. He was concerned with finding a faster way to compute the U.S. census, which in 1880 had taken nearly seven years. Therefore Hollerith invented a method, which used cards to store data information which he fed into a machine that compiled the results automatically. The punch cards not only served as a storage method and helped reduce computational errors, but furthermore significantly increased speed. Of extraordinary importance for the evolution of digital computers and artificial intelligence have furthermore been the contributions of the English mathematician and logician George Boole. In his postulates concerning the Laws of Thought (1854) he started to theorize about the true/false nature of binary numbers. His principles make up what today is known as Boolean algebra, the collection of logic concerning AND, OR, NOT operands, on which computer switching theory and procedures are grounded. Boole also assumed that the human mind works according to these laws, it performs logical operations that could be reasoned. Ninety years later Boole's principles were applied to circuits, the blueprint for electronic computers, by Claude Shannon.

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George Boole b. Nov. 2, 1815, Lincoln, Lincolnshire, England d. Dec. 8, 1864, Ballintemple, County Cork, Ireland English mathematician who helped establish modern symbolic logic and whose algebra of logic, now called Boolean algebra, is basic to the design of digital computer circuits. One of the first Englishmen to write on logic, Boole pointed out the analogy between the algebraic symbols and those that can represent logical forms and syllogisms, showing how the symbols of quantity can be separated from those of operation. With Boole in 1847 and 1854 began the algebra of logic, or what is now called Boolean algebra. It is basically two-valued in that it involves a subdivision of objects into separate classes, each with a given property. Different classes can then be treated as to the presence or absence of the same property.

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