My speciality. Шепелева М.А - 35 стр.

1'he ENIAC was completed in 1946, too late to be used in the war effort. Instead,
its first task was to perform a series of complex calculations that were used to help
determine the feasibility of the H-bomb. The use of the ENIAC for a purpose other
than that for which it was built demonstrated its general-purpose nature. Thus,
1946 ushered in the new era of the electronic computer, culminating years of
effort. The ENIAC continued to operate under BRL management until 1955, when
it was disassembled.

      The Second Generation: Transistor

        The first major change in the electronic computer came with the
replacement of the vacuum tube by the transistor. The transistor is smaller,
cheaper, and dissipated. Less heat than a vacuum tube but can be used in the same
way as a vacuum tube to construct computers. Unlike the vacuum tube, which
requires wires, metal plates, a glass capsule, and a vacuum, the transistor is a solid-
state device, made from silicon. The transistor was invented at Bell Labs in 1947
and by the 1950s had launched an electronic revolution. It was not until the late
1950s, however, that fully transistorized computers were commercially available.
IBM again 'was not the first company to deliver the new technology. NCR and,
more successfully, RCA were the front-runners with some small transistor
machines. IBM followed shortly with the 7000 series. The use of the transistor
detmes the second generation of computers. It has become widely accepted to
classify computers into generations based on the fundamental hardware technology
employed (Table 2.2). Each new generation is characterized by greater speed,
larger memory capacity, and smaller size than the previous one.
        But there are other changes as well. The second generation saw the
introduction of more complex arithmetic and logic units and control units, the use
of high-level programming languages, and the provision of system software with
the computer.
The second generation is noteworthy also for the appearance of the Digital
Equipment Corporation (DEC). DEC was founded in 1957 and, in that year,
delivered its first computer, the PDP-1. This computer and this company began the
minicomputer phenomenon that would become so prominent in the third
generation.

      The Third Generation: Integrated Circuits

        A single, self-contained transistor is called a discrete component.
Throughout the 1950s and early 1960s, electronic equipment was composed
largely of discrete components -- transistors, resistors, capacitors, and so on.
Discrete components were manufactured separately, packaged in their own
containers, and soldered or wired together onto masonite-like circuit boards, which
were then installed in computers, oscilloscopes, and other electronic equipment.
Whenever an electronic device called for a transistor, a little tube of metal