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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Central processing unit A CPU is the principal part of any digital computer system, generally composed of the main memory, control unit, and arithmetic-logic unit. It constitutes the physical heart of the entire computer system; to it is linked various peripheral equipment, including input/output devices and auxiliary storage units...

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Internet Protocol Number (IP Number) Every computer using TCP/IP has a 32 bit-Internet address, an IP number. This number consists of a network identifier and of a host identifier. The network identifier is registered at and allocated by a Network Information Center (NIC), the host identifier is allocated by the local network administration. IP numbers are divided into three classes. Class A is restricted for big-sized organizations, Class B to medium-sized ones as universities, and Class C is dedicated to small networks. Because of the increasing number of networks worldwide, networks belonging together, as LANs forming a corporate network, are allocated a single IP number.

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Cookie A cookie is an information package assigned to a client program (mostly a Web browser) by a server. The cookie is saved on your hard disk and is sent back each time this server is accessed. The cookie can contain various information: preferences for site access, identifying authorized users, or tracking visits. In online advertising, cookies serve the purpose of changing advertising banners between visits, or identifying a particular direct marketing strategy based on a user's preferences and responses. Advertising banners can be permanently eliminated from the screen by filtering software as offered by Naviscope or Webwash Cookies are usually stored in a separate file of the browser, and can be erased or permanently deactivated, although many web sites require cookies to be active. http://www.naviscope.com/ http://www.webwash.com/

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