The 17th Century: The Invention of the First "Computers" The devices often considered the first "computers" in our understanding were rather calculators than the sophisticated combination of hard- and software we call computers today. In 1642 Blaise Pascal, the son of a French tax collector, developed a device to perform additions. His numerical wheel calculator was a brass rectangular box and used eight movable dials to add sums up to eight figures long. Designed to help his father with his duties, the big disadvantage of the Pascaline was its limitation to addition. Gottfried Wilhelm von Leibniz, a German mathematician and philosopher, in 1694 improved the Pascaline by creating a machine that could also multiply. As its predecessor Leibniz's mechanical multiplier likewise worked by a system of gears and dials. Leibniz also formulated a model that may be considered the theoretical ancestor of some modern computers. In De Arte Combinatoria (1666) Leibniz argued that all reasoning, all discover, verbal or not, is reducible to an ordered combination of elements, such as numbers, words, colors, or sounds. Further improvements in the field of early computing devices were made by Charles Xavier Thomas de Colmar, a Frenchmen. His arithometer could not only add and multiply, but perform the four basic arithmetic functions and was widely used up until the First World War.

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some essential definitions some essential definitions in the field of cryptography are: - cryptoanalysis - cryptology - ciphers "Few false ideas have more firmly gripped the minds of so many intelligent men than the one that, if they just tried, they could invent a cipher that no one could break." (David Kahn) codes plaintext ciphertext to encipher/encode to decipher/decode The variants of encryption systems are endless. For deciphering there exists always the same game of trial and error (first guessing the encryption method, then the code). A help to do so is pruning. Once, after a more or less long or short period a code/cipher breaks. Monoalphabetic ciphers can be broken easily and of course are no longer used today but for games. for further information on codes and ciphers etc. see: http://www.optonline.com/comptons/ceo/01004A.html http://www.ridex.co.uk/cryptology/#_Toc439908851

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ciphers the word "cipher" comes from the Hebrew word "saphar", meaning "to number". Ciphers are mere substitutions. Each letter of the alphabet gets substituted; maybe by one letter or two or more. an example: PLAINTEXT a b c d e f g h i j k l m n o p q r s t u v w x y z CIPHERTEXT D E F G H I J K L M N O P Q R S T U V W X Y Z A B C

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Medieval universities and copying of books The first of the great medieval universities was established at Bologna. At the beginning, universities predominantly offered a kind of do-it-yourself publishing service. Books still had to be copied by hand and were so rare that a copy of a widely desired book qualified for being invited to a university. Holding a lecture equaled to reading a book aloud, like a priest read from the Bible during services. Attending a lecture equaled to copy a lecture word by word, so you had your own copy of a book, thus enabling you to hold a lecture, too. For further details see History of the Idea of a University, http://quarles.unbc.edu/ideas/net/history/history.html http://quarles.unbc.edu/ideas/net/history/his...

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