Computers are
classified according to the storage capacity, speed and the purpose for which
they are developed. These can be classified into three types:
1. Analog Computes
2. Digital Computers
3. Hybrid Computers
1. Analog computers: They
operate by measuring instead of counting. The name (derived from Greek word
analog) denotes that the computer functions by establishing similarities
between the two quantities. They are powerful tools for solving differential
equations.
2. Digital Computers:
These computers operate by counting All quantities are expressed as discrete
digits or numbers. These are useful for evaluating arithmetic expressions and
manipulations of data.
3. Hybrid Computers: Computers
which combine the features of analog and digital computers are known as Hybrid
computers.
A majority of the computers that are in use are digital.
These computers were essentially developed for computations. Later, the
developments in the computers led to the use of digital computers in variety of
applications. Depending on the use of applications, the digital computers are
classified into
1. Special Purpose
Computers: These are developed with a specific purpose. Some of the areas
where these computers are being used are – soil testing, drip irrigation,
medical scanning, traffic signals, spacecraft, rocket technology etc.,
2. General Purpose
Computers: These are developed to meet the requirements of several areas
such as simulation, solving mathematical equations, payroll and personnel
database. These computers are available in different sizes and capabilities and
are further classified (based on memory, speed, and storage) as follows.
a) Super
Computers: These have extremely large storage capacities and
computing speeds which are at least 10 times faster than other computers. These
are used for large scale numerical problems in scientific and engineering
disciplines such as electronics, weather forecasting etc. In India the indigenous super computer
was developed under the name Param.
b) Mainframe
Computers: They also have large storage and high computing speed
(but relatively lower than the super computers). They are used in applications
like weather forecasting, space applications etc., they support a large number
of terminals for use by a variety of users simultaneously, but are expensive
c) Mini
Computers: It is a medium sized computer with moderate cost,
available indigenously and used for large volume applications. It can serve
multi-users simultaneously
d) Micro
Computers: A micro computer is the smallest general purpose
processing system. Micro computers are also referred as personal computers
(PC).