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BASICS OF A COMPUTER
INTRODUCTION
Computers are very much in the
news nowadays. Be it in science fiction, or sensationally written news scoops or
serious technical or managerial articles or seminars. Computers always seem to
find a mention. However, the impression conveyed about them and their
capabilities vary in each.
As a result of this hype, people
have formed many and varied impressions about computers. Some feel that the
computer poses as an all -powerful being, out to malevolently dominate and
subjugate the human race. For some others, it is a friendly childlike robot,
magical in its powers but subordinate like a pet dog. At times, it is thought of
as an unfeeling contraption, or even as a mind-reading super being. Some see it
as an aid, some as a partially useful tool, still others as a job grabber. A few
actually feel it is too technical and sophisticated a machine to be put to any
useful work at all!
To the modern-day executive, not
really groomed for the use of computers, all this is somewhat confusing. He can
see computers everywhere. At the sales counter of a large shop he finds the
attendant confidently typing away at one and using something printed out by the
computer as a bill. Returning home, he sees the electricity and phone bills
waiting for him, printed on paper with perforations on both sides in the
peculiar fashion now familiar to him as that of a computer. The morning papers
are full of talk on super-computers or the Government's plan to computerize
something or the other. Trying to get away from it all and reserving his ticket
to Timbuktu, he is again confronted
with a computer terminal in the booking office. The executive feels somewhat
lost, curious and apprehensive. Sooner or later, he will have to decide whether
he too needs to use a computer. His organization may be on the way to acquiring
personal computers (commonly called PCs), or a minicomputer. He feels the need
to know more about them.
Computers are known to be a tool
for more effective management of resources, for their computing powers. What
exactly are they capable of? What are the pitfalls of using them? What are they
most suited for? And most important, how does someone not familiar with them go
about evaluating them and using them effectively? How well does he need to know
the internal structure of the computer People talk of bits and bytes and zeros
and ones and chips and what not-how much has to be essentially learnt before
touching a computer?
"A day in the life of …."
Let us take a day in an office and
pick up a few functions, examining each one with respect to the way it is
performed and see how a computer, if at all, can handle it.
The sales manager has instructed
her assistant to compile a list of all salespersons whose shortfall from their
individual target is more than 20 per cent. The list is required state-wise,
today.
The assistant first locates all
the relevant data, i.e. the state wise list of salespersons, their targets and
achievements. He then calculates the percentage shortfall for the salespersons
and marks out those with shortfall greater than 20 per cent. These are typed out
separately to be given to the sales manager. If the manager remembers now that
the had also wanted the list to salespersons who had exceeded the target by more
than 20 per cent, the assistant will have to go over the entire list again and
extract them.
The materials manager has to place
orders for all materials whose stock has fallen below the predefined re-order
level. For this, he has to draw up a list of all items where stock is less than
the re-order level. He then has to check for each the vendor on whom the order
has to be placed, and the price and the order quantity. The purchase orders can
then be prepared.
The production manager has to plan
the layout for cutting the sheet metal for the casing of the product they make.
Her objective is to minimize the 'scrap', i.e. the odd leftover sheet metal
pieces which can not be used. She may, if the problem is easy, sit down with a
paper and pencil and arrive at it by trial and error, or she may use some
algorithm of operations research for it.
The typist is typing out a long
report. Inadvertently, a paragraph of the manuscript gets left out. A section of
the report now has to be typed again.
In all these cases, a computer
could be used to reduce the tedium of the work, speed it up, and even so, be
more reliable in its output.
Taking the first case, what is
assistant sales manager doing? He has, to begin with a set of data - the details
of the salespersons, their targets and their achievements. To this he applies
the procedure outlined below.
- Examine each salesperson's record.
- If achieved sales are less than target set, calculate
Short = (target-achieved)/target)* 100
- If shortfall is greater than 20 per cent, mark out
that salesperson for getting typed later
- Keep doing steps 2 and 3 till salespersons are
covered.
- Get the list typed for the sales manager.
If the salespersons' records are
not arranged in state-wise order, an additional step of arranging the details in
state-wise order will need to be undertaken before the typing step.
Any device capable of processing
data in accordance to a laid out procedure can handle this work just as well, as
long as the procedure is laid out clearly, exhaustively and unambiguously. This
is precisely what a computer can do.
The magic box….
A computer is a device capable of
receiving both data and instructions, executing the instructions on the data and
giving the output accordingly. In the above case, given the steps for selection,
and the relevant salespersons' details, the computer will give the list the
sales manager requires.
Computers vary in their ability to
cope with data and instructions, the volume of data they can process, the type
of instructions they can execute efficiently, their speed and so on. They vary
in their architecture (how they are made), their size and complexity-they could
have just a single terminal such as a small office PC or a large number of
terminals such as a railway booking office.
What do computers have? Computers
have physical components and circuitry-called hardware which are capable of
executing a set of instructions written in a particular format called programs
which operate on data which the
computer can accept. A set of programs capable of solving a problem is called
software.
Let us now see what are the
advantages and disadvantages of a computer. We start with the disadvantages.
A Computer can do only what it is
told to do: As we saw, there in noting really magical inside the computer. A
computer is a device that does what it is instructed to do. If some instructions
are missing, they cannot be followed. If they are wrong, the work done will be
wrong. If the instructions are ambiguous then the working may seem erratic or
inconsistent. The computer cannot use common sense-it has none? Some things may
seem so obvious to the person instructing the computer that no instructions need
be given for it-but nothing is obvious to the computer.
The computer cannot judge the
veracity of the data : Again, the computer is a machine : It accept and process
whatever data is given to it. If the program to process the data does not verify
the correctness of the data, wrong data will remain undetected. And if the data
is wrong, the results will be wrong, at times even absurd. Abnormally
high electricity and phone bills can be produced if the meter reading decimal
point is omitted, and there is no check to highlight abnormally high readings.
An acronym used to express this is GIGO-Garbage In, Garbage Out. If the data
and/or the instructions are wrong, the output will also be wrong.
It is fairly obvious then that
using computers is not an offhand exercise. It needs care and caution, the user
needs to be systematic and properly. What, then, are the advantages of computers
that make it worth the while?
Computer handles large chunks of
data with ease: Being a machine has its advantages. The computer does not tire
handling large chunks of data. It does not show signs of fatigue which a human
being would if confronted with endless pages of computations to be performed.
The computer is able to handle big amounts of data without tiring. Reliability
of processing is constant. So, if your software-that is, your set of
instructions to the computer-is foolproof and the data correct, your results
will be correct regardless of the volume of data.
The computer is much, much faster
than the human being: The computer is based on electronic components and the
speed of the computer-that is, how fast it can compute-is measured in
microseconds and nanoseconds - one millionth of a second. Compare it with a
human being who would normally operate in minutes, and at best in seconds.
Obviously then, the difference is very palpable. The increased speed means that
work gets done much faster and things which seemed impossible manually can get
done - calculating the payroll of thousands of employees in a day or so.
The range of activities a computer
can handle is very high: Unlike the human being who can specialize at best in
one or two activities, properly instructed computers can handle a much larger
canvas. Of course, there is some degree of specialization even in computers and
what they are best at handling, but for normal commercial applications, the
range is more than sufficient.
It can function without human
intervention : When the work to be done is voluminous, to be able to sell
someone to do it and wald away for a relaxed weekend is a dream likely to remain
unfulfilled if the work is being done by human beings. But a properly instructed
computer can function continuously without human intervention for hours and even
days.
