Computers Development
A Computer is an electronic device that can receive a set of instructions,
or
program, and then carry out this program by performing calculations on
numerical
data or by compiling and correlating other forms of information.
The modern
world of high technology could not have come about except for the
development of
the computer. Different types and sizes of computers find uses
throughout
society in the storage and handling of data, from secret
governmental files to
banking transactions to private household accounts.
Computers have opened up a
new era in manufacturing through the techniques of
automation, and they have
enhanced modern communication systems. They are
essential tools in almost every
field of research and applied technology,
from constructing models of the
universe to producing tomorrow's weather
reports, and their use has in itself
opened up new areas of conjecture.
Database services and computer networks make
available a great variety of
information sources. The same advanced techniques
also make possible
invasions of privacy and of restricted information sources,
but computer
crime has become one of the many risks that society must face if it
would
enjoy the benefits of modern technology. (Gulliver 12-15) Imagine a
world
without computers. That would mean no proper means of communicating,
no
Internet, no video games. Life would be extremely difficult. Adults
would have
to store all their office work paper and therefore take up an
entire room.
Teenagers would have to submit course-works and projects
hand-written. All
graphs and diagrams would have to be drawn neatly and
carefully. Youngsters
would never have heard of 'video-games' and will have
to spend their free time
either reading or playing outside with friends. But
thanks to British
mathematicians, Augusta Ada Byron and Charles Babbage, our
lives are made a lot
easier. (Malone 5-6) There are two main types of
computers that are in use
today, analog and digital computers, although the
term computer is often used to
mean only the digital type. Analog computers
exploit the mathematical similarity
between physical interrelationships in
certain problems, and employ electronic
or hydraulic circuits to simulate the
physical problem. Digital computers solve
problems by performing sums and by
dealing with each number digit by digit. (Cringley
28-30) Hybrid
computers are those that contain elements of both analog and
digital
computers. They are usually used for problems in which large numbers
of
complex equations, known as time integrals, are to be computed. Data in
analog
form can also be fed into a digital computer by means of an analog-
to-digital
converter, and the same is true of the reverse situation.
(Cringley 31-32) The
French philosopher Blaise Pascal devised the first
adding machine, a precursor
of the digital computer, in 1642. This device
employed a series of ten-toothed
wheels, each tooth representing a digit from
0 to 9. The wheels were connected
so that numbers could be added to each
other by advancing the wheels by a
correct number of teeth. In the 1670s the
German philosopher and mathematician
Gottfried Wilhelm von Leibniz
improved on this machine by devising one that
could also multiply. The French
inventor Joseph Marie Jacquard, in designing an
automatic loom, used thin,
perforated wooden boards to control the weaving of
complicated designs.
During the 1880s the American statistician Herman Hollerith
conceived the
idea of using perforated cards, similar to Jacquard's boards, for
processing
data. Employing a system that passed punched cards over electrical
contacts,
he was able to compile statistical information for the 1890 U.S.
census.
(Hazewindus 44-48) Also in the 19th century, the British mathematician
and
inventor Charles Babbage worked out the principles of the modern
digital
computer. He conceived a number of machines, such as the Difference
Engine, that
were designed to handle complicated mathematical problems. Many
historians
consider Babbage and his associate, the British mathematician
Augusta Ada Byron
(Lady Lovelace, 1815-52), the daughter of the English poet
Lord Byron, the true
inventors of the modern digital computer. The technology
of their time was not
capable of translating their sound concepts into
practice; but one of their
inventions, the Analytical Engine, had many
features of a modern computer. It
had an input stream in the form of a deck
of punched cards, a "store"
for saving data, a "mill" for arithmetic
operations, and a printer
that made a permanent record. (Hazewindus 56-58)
Late in the 1960s the
integrated circuit, or IC, was introduced, making it
possible for many
transistors to be fabricated on one silicon substrate, with
inter- connecting
wires plated in place. The IC resulted in a further
reduction in price, size,
and failure rate. The microprocessor became a
reality in the mid-1970s with the
introduction of the large-scale integrated
(LSI) circuit and, later, the very
large scale integrated (VLSI) circuit,
with many thousands of interconnected
transistors etched into a single
silicon substrate. To return, then, to the
"switch-checking" capabilities of
a modern computer: computers in the
1970s generally were able to check
eight switches at a time. That is, they could
check eight binary digits, or
bits, of data, at every cycle. A group of eight
bits is called a byte, each
byte containing 256 possible patterns of ONs and
OFFs (or 1's and 0's).
Each pattern is the equivalent of an instruction, a part
of an instruction,
or a particular type of datum, such as a number or a
character or a graphics
symbol. The pattern 11010010, for example, might be
binary data-in this case,
the decimal number 210 (see NUMBER SYSTEMS)-or it
might tell the computer to
compare data stored in its switches to data stored in
a certain memory-chip
location. (Gulliver 30-33) The development of processors
that can handle 16,
32, and 64 bits of data at a time has increased the speed of
computers. The
complete collection of recognizable patterns-the total list of
operations-of
that a computer is capable is called its instruction set. Both
factors-number
of bits at a time, and size of instruction sets-continue to
increase with the
ongoing development of modern digital computers. (Dolotta
7-13) Major
changes in the use of computers have developed since it was first
invented.
Computers have expanded, via telephone lines, into vast nation-wide,
or
worldwide, networks. At each extremity of the network is a terminal
device,
or even a large computer, which can send jobs over the wire to the
central
computer at the hub of the network. The central computer performs
the
computation or data processing and sends the results over the wire to
any
terminal in the network for printing. Some computer networks provide a
service
called time-sharing. This is a technique in which software shifts the
computer
from one task to another with such timing that it appears to each
user at a
terminal that he has exclusive use of the computer. (Malone 59-62)
Other
developments in the industry are aimed at increasing the speed at which
data can
be transmitted. Improvements are being made continually in modems
and in the
communications networks. Some public data networks support
transmission of
56,000 bits per second (bps), and modems for home use are
capable of as much as
56kbps. (Chposky 40-42) CD's have developed a lot
over the past decade. At
first, they were used only for music. Now, there are
CD's from which we can play
PC games and watch movies. The games at
present are usually 3D. This means that
the game seems almost life-like or
virtual. One can spend hours playing games on
CD because they are
addictive. This is one of the main disadvantages of computer
games, because
the person prevents himself or herself from doing anything
educational or
engaging themselves in any physical activities. Another common
disadvantage
is that playing too much on the computer can cause bad eyesight.
But
there are a few educational games for young children to help them learn
and
understand things better. Games may not be all that good for an
individual, but
if seen how they are programmed one will realize that it is
not all easy to
program a game. (Gulliver 100-105) A few years ago, if one
were bored, they
would usually go to a video shop and rent a movie. Now one
can rent Movie CD's
and play them on the computer and special Movie CD
players, which are also
installed. We have made many advantages though the
years, and we are still
making more in leaps and bounds. Computers have
become a major part of our
lives, and will continue to be
forever.
Bibliography
Chposky, James. Blue Magic. New York: Facts
on File Publishing. 1988.
Cringley, Robert X. Accidental Empires.
Reading, MA: Addison Wesley Publishing,
1992. Dolotta, T.A. Data
Processing: 1940-1985. New York: John Wiley & Sons,
1985. Gulliver,
David. Silicon Valley and Beyond. Berkeley, Ca: Berkeley Area
Government
Press, 1981. Hazewindus, Nico. The U.S. Microelectronics Industry.
New
York: Pergamon Press, 1988. Malone, Michael S. The Big Scare: The
U.S.
Computer Industry. Garden City, NY: Doubleday & Co., 1985.