i)Computer history
and its generations
A generation
refers to the state of improvement in the development of a product. This term is also used in the different
advancements of computer technology.
With each new generation, the circuitry has gotten smaller and more
advanced than the previous generation before it. As a result of the miniaturization, speed,
power, and memory of computers has proportionally increased. New discoveries are constantly being developed
that affect the way we live, work and play.
·
The First
Generation: 1946-1958 (The Vacuum Tube
Years)
The first generation computers were huge,
slow, expensive, and often undependable.
In 1946two Americans, Presper Eckert, and John Mauchly built the ENIAC
electronic computer which used vacuum tubes instead of the mechanical switches
of the Mark I. The ENIAC used thousands
of vacuum tubes, which took up a lot of space and gave off a great deal of heat
just like light bulbs do. The ENIAC led
to other vacuum tube type computers like the EDVAC (Electronic Discrete
Variable Automatic Computer) and the UNIVAC I (UNIVersal Automatic Computer).
The vacuum tube was an extremely important
step in the advancement of computers.
Vacuum tubes were invented the same time the light bulb was invented by
Thomas Edison and worked very similar to light bulbs. It's purpose was to act like an amplifier and
a switch. Without any moving parts,
vacuum tubes could take very weak signals and make the signal stronger (amplify
it). Vacuum tubes could also stop and
start the flow of electricity instantly (switch). These two properties made the ENIAC computer
possible.
The ENIAC gave off so much heat that they had
to be cooled by gigantic air conditioners.
However even with these huge coolers, vacuum tubes still overheated
regularly. It was time for something
new.
·
The
Second Generation: 1959-1964 (The Era of
the Transistor)
The transistor computer did not last as
long as the vacuum tube computer lasted, but it was no less important in the
advancement of computer technology. In
1947 three scientists, John Bardeen,William Shockley, and Walter Brattain
working at AT&T's Bell Labs invented what would replace the vacuum tube
forever. This invention was the
transistor which functions like a vacuum tube in that it can be used to relay
and switch electronic signals.
There were obvious differences between the
transisitor and the vacuum tube.
The
transistor was faster, more reliable, smaller, and much cheaper to build than a
vacuum tube. One transistor replaced the
equivalent of 40 vacuum tubes. These
transistors were made of solid material, some of which is silicon, an abundant
element (second only to oxygen) found in beach sand and glass. Therefore they were very cheap to
produce. Transistors were found to
conduct electricity faster and better than vacuum tubes. They were also much smaller and gave off
virtually no heat compared to vacuum tubes.
Their use marked a new beginning for the computer.
Without this invention, space travel in the
1960's would not have been possible.
However, a new invention would even further advance our ability to use
computers.
·
The Third
Generation: 1965-1970 (Integrated
Circuits - Miniaturizing the Computer)
Transistors were a tremendous breakthrough
in advancing the computer. However no
one could predict that thousands even now millions of transistors (circuits)
could be compacted in such a small space.
The integrated circuit, or as it is sometimes referred to as
semiconductor chip, packs a huge number of transistors onto a single wafer of
silicon.
Robert Noyce of Fairchild Corporation and Jack
Kilby of Texas Instruments independently discovered the amazing attributes of
integrated circuits. Placing such large
numbers of transistors on a single chip vastly increased the power of a single
computer and lowered its cost considerably.
Since the invention of integrated circuits,
the number of transistors that can be placed on a single chip has doubled every
two years, shrinking both the size and cost of computers even further and
further enhancing its power. Most
electronic devices today use some form of integrated circuits placed on printed
circuit boards-- thin pieces of bakelite or fiberglass that have electrical
connections etched onto them -- sometimes called a mother board.
These third generation computers could carry
out instructions in billionths of a second.
The size of these machines dropped to the size of small file cabinets.
Yet, the single biggest advancement in the computer era was yet to be discovered.
·
The
Fourth Generation: 1971-Today (The
Microprocessor)
This generation can be characterized by
both the jump to monolithic integrated circuits(millions of transistors put
onto one integrated circuit chip) and the invention of the microprocessor (a
single chip that could do all the processing of a full-scale computer). By putting millions of transistors onto one
single chip more calculation and faster speeds could be reached by
computers. Because electricity travels
about a foot in a billionth of a second, the smaller the distance the greater
the speed of computers.
However what really triggered the
tremendous growth of computers and its significant impact on our lives is the
invention of the microprocessor. Ted
Hoff, employed by Intel (Robert Noyce's new company) invented a chip the size
of a pencil eraser that could do all the computing and logic work of a
computer. The microprocessor was made to
be used in calculators, not computers.
It led, however, to the invention of personal computers, or
microcomputers.
It wasn't until the 1970's that people began
buying computer for personal use. One of
the earliest personal computers was the Altair 8800 computer kit. In 1975 you could purchase this kit and put
it together to make your own personal computer.
In 1977 the Apple II was sold to the public and in 1981 IBM entered the
PC (personal computer) market.
Today we have all heard of Intel and its Pentium®
Processors and now we know how it all got started. The computers of the next generation will
have millions upon millions of transistors on one chip and will perform over a
billion calculations in a single second.
There is no end in sight for the computer movement.
·
Fifth
Generation (Present and Beyond) Artificial Intelligence
Fifth generation computing devices, based on
artificial intelligence, are still in development, though there are some
applications, such as voice recognition, that are being used today. The use of
parallel processing and superconductors is helping to make artificial
intelligence a reality. Quantum computation and molecular and nanotechnology
will radically change the face of computers in years to come. The goal of
fifth-generation computing is to develop devices that respond to natural
language input and are capable of learning and self-organization.
ii) Computer components
iii)Advantages of
using computer
·
Storage
While human brains can contain a high level
of information to use in making a decision, a computer's "brain" can
contain even more data and information, depending on the storage space it is
connected to. With a higher capacity for more data, especially data that a
human brain might not retain, such as complex equations, more information can
be incorporated into the "brain" or algorithm of the computer in its
decision making, leading to better results.
·
Speed and
Accuracy
Computers can process information much
faster than a human brain. One advantage to computers making decisions is that
you will have decisions made faster and more accurately than a human brain,
which may get hung up with different factors involving the decision, leading to
slower overall results. Also, unlike people who can become tired or suffer from
a lack of concentration and deliver inaccurate decisions, a well-tuned computer
is always alert and can process reams of information without growing bored or
tired, leading to more precise results.
·
High Cost
The high cost of purchasing the right
computer equipment, including a high amount of computer memory and store, is
one disadvantage to computer technology in decision making. Also, the cost of a
computer professional to write the algorithm you'll need for your type of
decision can come at a high price. By the time your equipment is purchased and
your algorithm is written, it may also already be obsolete since technology is
constantly advancing and building on what already works to make it better.
·
Employee
Morale and Subjectivity
With a computer making decisions, certain
managers may feel that their own decision-making skills aren't seen as
important, which can diminish employee morale. Also, unlike people who can be
subjective and rational, computers can only be rational. By eliminating
subjectivity in the decision-making process, the result may lack certain
elements you are concerned about.