Learning Objective: Identify computer
Computer applications fall into a variety of broad
Information retrieval is one such
application, or in a narrower sense, indexing or
cataloging. Information is stored under a variety of
key words or index headings. By calling up one of
these headings, a listing of all or part of the
information will be outputted by the computer.
Another application is simulation. This involves
simulating the operation of a new computer by using
an older computer model. In this way, design
deficiencies can be identified without going through
the time-consuming and expensive process of
building the newer unit.
Real-time control of a production process is
another application. For example, the petroleum and
chemical industries put this process to good use. The
computer can detect minute changes in the production
process and initiate immediate corrective action.
The advent of personal (home) computers has
greatly expanded the computer-use horizon from the
routine upkeep of a checkbook balance to the more
complex functions of financial planning, home
security, and computer video games.
The application of the computer and its functions
is virtually endless. For this reason, there are some
people who believe that the computer will soon
control everything and everyone. This is not
necessarily the case, however, as computers can do
only what their creators have intended them to do.
The computer enables people to do more than they
have been able to do in the past. For example,
computations that required years to calculate by
human methods can now be accomplished in a matter
of moments by modern computers. This has become
particularly evident in our space program. The ability
to put a man on the moon and send Voyager I and
Voyager II on their journeys would have been
impossible without the use of computers. Fears over
job losses are, for the most part, needless. While
some jobs may be eliminated, new ones are created.
Thus, a worker may have to learn a new skill. For
example, a laborer may have to be retrained as a
computer programmer or operator. Rather than
destroying jobs, the computer
where none existed before.
TYPES OF COMPUTERS
Identify the types of
computers and the analytical processes used
by each type.
In general, there are two basic types of
computers analog and digital.
The term analog, as applied to computers,
pertains to representation by means of continuously
variable physical quantities. For example, an analog
computer can be a device that solves problems by
setting up electrical circuits that represent the
physical equivalents of certain phenomena. Then,
measurements are made as these circuits are varied in
accordance with changes in the phenomena. The
analog computer is by no means restricted to
electrical circuits as equivalents. The physical
equivalents may be gear trains, gases, fluids, etc.
Analog computers, because of their nature, have
some inherent limitations. The use of physical
equivalents limits their versatility. They are limited to
performing only the tasks for which they were
designed or, in certain instances, closely related tasks.
A digital computer is a device that solves
problems by manipulating the numerical equivalents
of phenomena in accordance with mathematical and
logical processes. These numerical equivalents may
be expressed as binary numbers, octal numbers,
decimal numbers, etc. In an electronic digital
computer, the numerical equivalents are generally
expressed as binary numbers 1 or 0. Values of voltage
and current are used to represent the 1s and 0s.
The versatility of digital computers is based on
the fact that they use numerical equivalents not only
to represent the data to be processed, but also the
instructions for processing the data. In other words,
digital computers are generally provided with a wide
variety of instructions. They are designed to respond
in certain ways to the numerical equivalent of these
Programming is merely a matter of
modifying and/or arranging these instructions so that
the computer will respond in a predictable manner to
a given situation. While much more versatile than an
analog system, digital systems are still limited as to