The term computer is derived from the word
compute. A computer is an electronic device that
takes data and instruction as an input from the
user, processes data, and provide useful
information known as output. This cycle of
operation of a computer is known as the input-
process-output cycle and as in shown in figure.
CLASSIFICATION OF COMPUTER
Computer is classified into several
categories depending on their computing
ability and processing speed. These include
The term microcomputer is generally synonymous with
personal computer, or a computer that depends on a
microprocessor. Microcomputers are designed to be used by
individuals, whether in the form of PCs, workstations or
notebook computers. A microcomputer contains a CPU on a
microchip, a memory system (typically ROM and RAM), a bus
system and I/O ports, typically housed in a motherboard.
A minicomputer is a medium-sized computer that is more powerful than the
microcomputer. An important distinction between the microcomputer and a
minicomputer is that a minicomputer is usually design to serve multiple
users simultaneously. A system that support multiple users is called a
multiterminal, time-sharing system. Minicomputer are the popular
computing systems among research and business organizations today.
They are move expensive than microcomputer.
Mainframe computer are those computer, which help in
handling the information processing of various organization
like banks, insurance companies, hospitals and railways.
Mainframe computer placed on a central location and are
connected to several user terminals, which can act as access
stations and may be located in a same building. Mainframe
computer is larger and expensive in comparison to other
Supercomputer are the most powerful and expensive
computers available. Supercomputers are primarily used for
complex scientific application, which need a higher level of
processing. Some of these application include weather
forecasting, climate research, molecular modeling used for
chemical compounds, aeroplane simulation and nuclear fusion
The electronic device is known as hardware.
Computer Hardware is the physical part of the computer
system, the machinery and equipment.
Parts of the computer “you can feel”
Internal hardware devices include motherboards, hard
drives, and RAM. External hardware devices include
monitors, keyboards, mice, printers, and scanners.
The internal hardware parts of a computer are often
referred to as components, while external hardware
devices are usually called peripherals. Together, they all fall
under the category of computer hardware.
Software is a collection of computer programs and
related data that provide the instructions for telling
a computer what to do and how to do it. In other
words, software is a conceptual entity which is a
set of computer programs, procedures, and
associated documentation concerned with the
operation of a data processing system. We can
also say software refers to one or more computer
programs and data held in the storage of the
computer for some purposes
Input device captures information and translates it into a form
that can be processed and used by other parts of your computer.
Output devices take information within your computer and
present it to you in a form that you can understand.
USAGE OF COMPUTER
Computer is the best companion of our
• Network attached storage
• Media Server
• Graphics design
• On-line banking
• Social Networking
• Knowledge sharing