HISTORY OF COMPUTER
Computer
A computer is a programmable electronic device that
accepts raw data as input and processes it with a set of
instructions to produce the result as output. It renders
output just after performing mathematical and logical
operations and can save the output for future use.
Types of Computer
On the basis of data handling capabilities, the computer is of three types:
1) Analog Computer
2) Digital Computer
3) Hybrid Computer
1) Analog computers
Analog computers are designed to process analog data.
Analog data is continuous data that changes continuously
and cannot have discrete values. We can say that analog
computers are used where we don't need exact values
always such as speed, temperature, pressure and current.
Analog computers directly accept the data from the
measuring device without first converting it into numbers
and codes. Speedometer and mercury thermometer are
examples of analog computers.
2) Digital computer
Digital computer is designed to perform calculations and
logical operations at high speed. It accepts the raw data as
input in the form of digits or binary numbers (0 and 1) and
processes it with programs stored in its memory to
produce the output. All modern computers like laptops,
desktops including smartphones that we use at home or
office are digital computers.
3) Hybrid computer
Hybrid computer has features of both analog and digital
computer. It is fast like an analog computer and has
memory and accuracy like digital computers. It can
process both continuous and discrete data.
It accepts analog signals and convert them into digital
form before processing. So, it is widely used in specialized
applications where both analog and digital data is
processed. For example, a processor is used in petrol
pumps that converts the measurements of fuel flow into
quantity and price. Similarly, they are used in airplanes,
hospitals, and scientific applications.