Компьютерная техника. Еремина Н.В. - 17 стр.

accomplish the same thing with one instruction.
     These computers can be of two types: digital or analog. The digital computer or
general-purpose computer as it is often make up about 90% of the large computers
now in use. It gets name from the name of the data that are presented to it and which
consist of digits. The digital computer can do calculations in steps at tremendous
speed and with great accuracy. Digital computer programming is by far the most
commonly used in electronic data processing for business or statistical purposes. The
analog computer works something like a car speedometer, in that it continuously
works out calculations. It is used essentially for problems invo1ving measurements. I
t can simu1ate or imitate different measurements by electronic means. Both of these
types are made of electronic computers that may require a larger              room to
accommodate them. At present, the digital computer is capable of doing anything the
analog once did. Moreover, it is easier to program and cheaper to operate. A new
type of scientific computer system called the hybrid computer has now been
produced that combines the two types into one.

     3.3 Text 3
     Minicomputers

     Until the mid – 1960s, digita1 computers were powerful, physically large and
expensive . What was rea11yneeded were computers of less power, a smaller memory
capacity and whiteout such a large array of peripheral equipment. This need was
partially satisfied by the rapid improvement in performance of the semiconductor
devices ( transistors ), and their incredib1e reduction in size, cost and power – al1 of
which led to the development of the minicomputer or mini for short.
     Although there is no exact definition of a minicomputer, it is generally
understood to refer to a computer whose mainframe is physically small, and has a
fixed word length between 8 and 32 bits.
A large number of peripherals hove been developed especially for use in systems
built round minicomputers. They include magnetic tape, cartridges and cassette, small
disk units and a large variety of printers and consoles.
     Since the operating environment for most minis is far less varied and complex