Welcome to the computer world. Practice materials for 1st year students. Еранина Т.И - 40 стр.

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        tronically, Aiken's machine is often classified as a computer because
        its instructions, which were entered by means of a punched paper tape,
        could be altered. The computer could create ballistic tables used by
        naval artillery.
                    The relay computer had its problems. Since relays are elec-
        tromechanical devices, the switching contacts operate by means of
        electromagnets and springs. They are slow, very noisy and consume a
        lot of power.

                         The ABC (1939-1942)

                    The work on introducing electronics into the design of com-
        puters was going on.
                    The gadget that was the basis for the first computer revolu-
        tion was the vacuum tube, an electronic device invented early in the
        twentieth century. The vacuum tube was ideal for use in computers. It
        had no mechanical moving parts. It switched flows of electrons off and
        on at rates far faster than possible with any mechanical device. It was
        relatively reliable, and operated hundreds of hours before failure. The
        first vacuum tube computer was built at Iowa University at about the
        same time as the Mark I. The computer, capable to perform thousands
        of related computations, was called ABC, the Atanasoff-Berry
        Computer, after Dr. John Atanasoff, a professor of physics and his assis-
        tant, Clifford Berry. It used 45 vacuum tubes for internal logic and
        capacitors for storage. From the ABC a number of vacuum-tube digital
        computers developed.
                    Soon the British developed a computer with vacuum tubes
        and used it to decode German messages.

Task 8. Practice finding the main idea, major details in the text and give a
        summary of it.

                     Four generations of computers
                   The first vacuum tubes computers are referred to as first gen-
         eration of computers, and the approximate period of their use was from
         1950 to 1959. UNIVAC 1 (Universal Automatic Computer) is an
         example of these computers which could perform thousands of
         calculations per second. Those devices were not only bulky, they were
         also unreliable. The thousands of vacuum tubes emitted large amounts
         of heat and burned out frequently.
                   The transistor, a smaller and more reliable successor to the
         vacuum tube, was invented in 1948. So-called second generation