1. CLASSIFICATION OF COMPUTERS
We know that computer is an electronic device to perform mathematical and logical
calculations. The history of computers tells us that “Charles Babbage” is called the
“Father of Computers”. Now in this chapter we are trying to describe the types of
computers and elaborate classification of computers. Computers can be classified in
various ways depending upon its size, memory capacity, processing speed etc. Here
we are going to discuss the broadly accepted classification of computer. The criteria
of this classification is as discussed above. Computers are classified into four cat-
egories:
1. Mainframe Computers
2. Mini Computers
3. Micro Computers
4. Super Computers
Now lets have an overview of general characteristics of each category.
1. Mainframe Computers.
l They are big computer systems sensitive to temperature, humidity, dust etc.
l Qualified & trained operators are required to operate them.
l They have wide range of peripherals attached.
l They have large storage capacity.
l They can use wide variety of softwares.
l They are not user friendly.
l They can be used for more mathematical calculations.
l They are installed in large commercial places or government organizations.
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2. M1 - Learning Computers
2. Mini Computers.
l They have less memory & storage capacity than mainframe
computers.
l They offer limited range of peripherals.
l Limited range of softwares can be used by them.
l The end users can directly operate it.
l They are not very sensitive to the external environment and
hence are more generalised.
l They are used for data processing.
3. Micro Computers.
l They brought revolution in the history of computers.
l They are also known as Personal Computers.
l They are cheap and user friendly.
l The main components are Monitor, CPU, Keyboard, Mouse,
Speakers, Modem and Printer.
l They are having limited peripherals attached to them.
l This type of computers can use wide range of softwares.
l They are used as desktops either in offices or even homes.
l Their operation can be easily learnt by anyone having logical
apptitude.
l Children enjoy playing games & watching movies in these
computers.
l Most popular micro computer’s processing chip manufactur-
ing company is Intel.
4. Super Computers.
l They are huge computers installed in space centres,
nuclear power stations etc.
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3. Classification of Computers
l They are used for performing complex mathematical
calculations.
l Only scientists and mathematicians can operate them.
l They are having huge memories & tremendous
processing speed.
l They are used for whether forecasting, animation graphics etc.
Energy Capsules?
The Maths whiz Ms. Shakuntla Devi's name was entered in the Guinness Book of
Records in 1980 when she multiplied two 13-digit numbers : 7,686,369,774,870 by
2,4265,099,745,779 accurately in 28 seconds. In 1977 she beat a computer-the
UNIVAC-by 10 seconds. This was when she calculated the 23rd
root of a 201-digit number in 50 seconds.
Energy Capsules?
The microprocessor of a microcomputer comprises the Control Unit and
the Arithmetic and Logic Unit. It is manufactured as a chip. Most popu-
lar chip manufacturing company is Intel.
Energy Capsules?
Bit is the short form for binary digit. It includes either of the two digits 0 and 1 in
the binary number system.
Byte is a fixed number of bits that can be treated as a unit by the computer hard-
ware.
1 byte = 8 bits
The letters B and b are commonly used as symbols for byte as in KB (kilobyte);
MB (megabyte); and GB (gigabyte).
1 KB = 1024 bytes
1 MB = 1024 KB
1 GB = 1024 MB
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4. M1 - Learning Computers
Energy Capsules?
The centre for Development of Advanced Computing (C-DAC) in Pune recently
unveiled Param 10000, which is now Asia's largest supercomputer. The 100 giga
flops (giga means ten raised to the power nine, 109) supercomputer can perform
100 billion calculations per second.
Lets Revise
l ``Charles Babbage'' is known as ``Father of Computer''.
l Computers are broadly categorised into four types: Main-
frame, Mini, Micro and Super Computers.
l The popular home PCs called personal computers belongs to
the Microcomputers category.
l Super computers are fastest computers used for scientic re-
search, Wheather forecasting, graphic animations etc.
Try Yourself
1. How are computers classified on the basis of their size, ca-
pacity and speed?
2. Write a brief note on mainframe computers.
3. What do you know about minicomputers?
4. Describe the main features and characteristics of microcom-
puters.
5. Write a brief note on supercomputers.
6. Distinguish between mainframe, mini, micro and
supercomputers.
7. Mention the places where micro computers are used.
8. Collect some more data about supercomputers and discuss
with your teacher.
9. Which computer is available in your school? What are the
peripherals that are attached to it? In which type of comput-
ers will you place your school computer.
10. Write the utility areas of personnel computers.
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