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    History of the computer A Brief History of Computers and Networks



    عدد المساهمات : 10329
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    تاريخ التسجيل : 08/04/2009
    العمر : 25

    History of the computer A Brief History of Computers and Networks

    مُساهمة من طرف GODOF في الأحد 7 مارس - 19:18

    Part I

    Webster's Dictionary defines "computer" as any programmable electronic device that can store, retrieve, and process data. The basic idea of computing develops in the 1200's when a Moslem cleric proposes solving problems with a series of written procedures.

    As early as the 1640's mechanical calculators are manufactured for sale. Records exist of earlier machines, but Blaise Pascal invents the first commercial calculator, a hand powered adding machine. Although attempts to multiply mechanically were made by Gottfried Liebnitz in the 1670s the first true multiplying calculator appears in Germany shortly before the American Revolution.

    In 1801 a Frenchman, Joseph-Marie Jacquard builds a loom that weaves by reading punched holes stored on small sheets of hardwood. These plates are then inserted into the loom which reads (retrieves) the pattern and creates(process) the weave. Powered by water, this "machine" came 140 years before the development of the modern computer.

    Ada Lovelace

    Shortly after the first mass-produced calculator(1820), Charles Babbage begins his lifelong quest for a programmable machine. Although Babbage was a poor communicator and record-keeper, his difference engine is sufficiently developed by 1842 that Ada Lovelace uses it to mechanically translate a short written work. She is generally regarded as the first programmer. Twelve years later George Boole, while professor of Mathematics at Cork University, writes An Investigation of the Laws of Thought(1854), and is generally recognized as the father of computer science.

    The 1890 census is tabulated on punch cards similar to the ones used 90 years earlier to create weaves. Developed by Herman Hollerith of MIT, the system uses electric power(non-mechanical). The Hollerith Tabulating Company is a forerunner of today's IBM.

    Just prior to the introduction of Hollerith's machine the first printing calculator is introduced. In 1892 William Burroughs, a sickly ex-teller, introduces a commercially successful printing calculator. Although hand-powered, Burroughs quickly introduces an electronic model.

    In 1925, unaware of the work of Charles Babbage, Vannevar Bush of MIT builds a machine he calls the differential analyzer. Using a set of gears and shafts, much like Babbage, the machine can handle simple calculus problems, but accuracy is a problem.

    The period from 1935 through 1952 gets murky with claims and counterclaims of who invents what and when. Part of the problem lies in the international situation that makes much of the research secret. Other problems include poor record-keeping, deception and lack of definition.

    In 1935, Konrad Zuse, a German construction engineer, builds a mechanical calculator to handle the math involved in his profession. Shortly after completion, Zuse starts on a programmable electronic device which he completes in 1938.

    John Vincent Atanasoff
    Courtesy Jo Campbell
    The Shore Journal

    John Vincent Atanasoff begins work on a digital computer in 1936 in the basement of the Physics building on the campus of Iowa State. A graduate student, Clifford (John) Berry assists. The "ABC" is designed to solve linear equations common in physics. It displays some early features of later computers including electronic calculations. He shows it to others in 1939 and leaves the patent application with attorneys for the school when he leaves for a job in Washington during World War II. Unimpressed, the school never files and ABC is cannibalized by students.

    The Enigma
    Courtesy U. S. Army

    The Enigma, a complex mechanical encoder is used by the Germans and they believe it to be unbreakable. Several people involved, most notably Alan Turing, conceive machines to handle the problem, but none are technically feasible. Turing proposes a "Universal Machine" capable of "computing" any algorithm in 1937. That same year George Steblitz creates his Model K(itchen), a conglomeration of otherwise useless and leftover material, to solve complex calculations. He improves the design while working at Bell Labs and on September 11, 1940, Steblitz uses a teletype machine at Dartmouth College in New Hampshire to transmit a problem to his Complex Number Calculator in New York and receives the results. It is the first example of a network.

    First in Poland, and later in Great Britain and the United States, the Enigma code is broken. Information gained by this shortens the war. To break the code, the British, led by Touring, build the Colossus Mark I. The existence of this machine is a closely guarded secret of the British Government until 1970. The United States Navy, aided to some extent by the British, builds a machine capable of breaking not only the German code but the Japanese code as well.

      الوقت/التاريخ الآن هو الأربعاء 22 فبراير - 2:12