Computer is no longer something new and magical to many
people nowadays, because many families now have at least one
computer in their homes. It is without doubt that there are
thousands and millions of computer users in the country, but is
it ever possible for all of them to explain how a computer works?
No. Alright, can they even classify the components of a computer
appropriately? Not quite. They may know how to describe the
physical appearance of a computer and they will probably
include two or three other terms as well, such as monitor,
keyboard or a mouse. Nonetheless, classification of a computer
should not be done this way. In fact, a computer can be broken
down into three distinct categories, namely output, input and
The term 'output' consists of all components that display
words and graphics so that a person can see them. Many people
can easily understand why the monitor is a form of output device
since it is the screen that tells them what the computer is
actually doing. Simply put, without a monitor, the computer
itself is basically useless. Another form of output, which is
rarely noticed by many computer users however, is the printer.
Many people have probably used a printer before, but it is just
that they never realize it is also a form of output.
As opposed to 'output', 'input' consists of components that
take in information from the users themselves so that the
computer will know the tasks it is supposed to perform and
accomplish. The keyboard is classified as a form of input
because this is where the users enter commands and text. There
are many other forms of input as well. Nonetheless, many people
just don't realize them, or are too lazy to classify them. For
instance, the mouse belongs to input, since it provides a
floating pointer on the screen so that the users can access
commands faster and easier. The scanner is another form of
input, because it acts like a photocopier, except it scans the
image and makes it onto the computer screen instead of onto a
piece of paper.
The CPU, Central Processing Unit is probably the most
important category of the three. As the name implies, it is the
soul of a computer, very much alike the human brain. For
unknown reasons though, people often call the CPU a computer.
This is absolutely incorrect. The word computer is merely a
general term which must always include all the three categories
in order to operate. Perhaps the constituents of a CPU itself
should be mentioned. Simply stated, this central unit must have
memory blocks to store data temporarily; disk drives to store
data permanently; and last but not least, the main processor
chip which performs all the jobs and mathematical calculations,
as well as determines the speed of a CPU.
These are the three categories that the readers must know
should they need to classify a computer again in the future.
Also, it can be seen that a computer is not as simple as many
people think it is, for it consists of many internal components
which are often neglected and ignored. It should also be
emphasized that the components listed in this essay are not the
only ones available, since developers and manufacturers will
continue to bombard the market with newer and more sophisticated