Classification of Computers

 

We can classify Computers into various types:

1)            According to Function

2)            According to Purpose

3)            According to Size and Capacity

 

1)       According to Function

According to function Computers can be divided into three types:

a.            Digital Computers

b.            Analogue Computers

c.            Hybrid Computers

 

a.       Digital Computers

In very simple words Computers which accept and provide data in the form of digits or Computers which operate data in discrete form are called Digital Computers. All the expressions in Digital Computers are coded into binary digits (0 and 1) inside the Computer and it manipulates them at a very fast speed. A Digital Computer can perform arithmetic and logical operation. Data and instructions are fed into the Computer through an input device in the form of different electrical signals. After manipulation the results are displayed on monitor or any other output device. Digital Computers are easy to program and can be used for multi-purposes.

 

b.       Analogue Computers

Analogue Computers are special purpose Computers and mostly used in engineering and medical fields. Their input and output is in the form of waves. They work in supply of continuous electrical signals. As compared to Digital Computers, analogue Computers have very limited memory and the accuracy of these machines are not too good. But these machines are faster than Digital Computers.

 

c.       Hybrid Computers

Sometime, the best features of analogue and Digital Computers are combined to create a new family of Computers called “Hybrid Computers”. Hybrid Computers have characteristics of both Digital and analogue Computers i.e. speed of analogue Computers and accuracy of Digital Computers. Therefore, hybrid Computers have ability to accept data, process data and provide results/output in both analogue (continuous) and Digital (discrete) form.

 

2)       According to Purpose

According to purpose, Computers can be divided into two types:

a.            General Purpose Computers

b.            Special Purpose Computers

 

a.       General Purpose Computers

General-purpose Computers are so designed that they can solve a large variety of problems by using different programs. Most Digital Computers are general-purpose Computers.

 

b.       Special Purpose Computers

Special purpose Computers are designed to solve a special problem. Most analogue Computers are special purpose Computers.

 

3.       According to Size and Capacity

All Digital Computers operate in the same way but there are several factors that make Computers different from each other. These factors are physical size, speed, memory and capacity. So according to size and capacity these Computers can be classified into four types.

a.            Super Computers

b.            Main Frame Computers

c.            Mini Computers

d.            Micro Computers (PCs)

 

a.       Super Computers

Super Computers are very big in size. They are the most powerful type of Digital Computers, having many surprising features. Their features include Artificial Intelligence, highest speed and Array processing capability.

 

b.       Main Frame Computers

Main Frame Computer is large size Computer (little bit smaller as compared to Super Computer). Its terminals are placed at many required places. These terminals are connected with the system unit of Main Frame Computer.

It can be used by hundreds of users at a time through their separate terminals.

 

c.       Mini Computers

Mini Computers have small memory and size as compared to main frame or Super Computer. Mini Computers do all the jobs of Main Frame Computers but they are used in small organizations and they are cheaper than Super or Main Frame Computers. Mini Computers are also multi user Computers.

 

d.       Micro Computers (PCs)

It is the most popular form of Digital Computers. It is frequently used in all fields of life. It is general-purpose Computer. It is usually consisted of keyboard, system unit, monitor, disk drives and a printer.

As a Micro-Computer is designed for single person so it is known as Personal Computer (PC).

Micro-Computers can be further divided into four types. They all perform nearly equal tasks but they are divided according to their Physical Shape.

·      Tower Computers

·      Mini Tower Computers

·      Desktop Computers

·      Laptop Computers

 

·      Tower & Mini Tower Computers

Both Tower & Mini Tower Computers have casing (system unit) standing like a tower beside monitor.

 

·      Desktop Computers

Desktop Computers have system unit lying under monitor.

 

·      Laptop Computers

Businessmen mostly use laptop Computers because these Computers are smaller in size, not so heavy and easy to carry. All the components necessary for Computer are fixed together in a briefcase like shape. Laptop Computers are expensive as compared to Tower, Mini Tower or Desktop Computers.