3. The term COMPUTER is derived from the
word COMPUTE. A computer is an electric
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 is shown
in figure.
4. Computer is classified into several categories
depending on their computing ability and
processing speed.These includes
▪ Microcomputer
▪ Minicomputer
▪ Mainframe Computer
▪ Supercomputer
5. The term MICROCOMPUTER is generally
synonymous with PERSONAL
COMPUTER, or a computer that depends
on a MICROPROCESSOR.
Microcomputers are used by Individuals, in
the form of PCs,Workstations or Laptops. A
microcomputer contains a CPU, a memory
system (ROM and RAM), a bus system and
I/O ports, housed in a motherboard.
6. 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. Minicomputer are the
popular computing systems among
Research and Business organizations today.
7. 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.
8. SUPERCOMPUTERS are the most
powerful and expensive computers
available. Supercomputers are used for
Complex Scientific Application, which
need a higher level of processing.These
application include Weather Forecasting,
Climate Research, Molecular Modeling
used for chemical compounds, Airplane
Simulation and Nuclear Fusion research.
9. Computer HARDWARE is the physical
part of the computer system. Parts of the
computer “You Can Feel”. Internal
hardware devices include Motherboards,
Hard Drives, and RAM. External
hardware devices include Monitor,
Keyboard, Mice, Printer, and Scanner.
The internal hardware parts of a computer
are often referred to as COMPONENTS,
while external hardware devices are
usually called PERIPHERALS.Together,
they all are called computer hardware.
10. 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.
11. INPUT DEVICE captures information and
translates it into a form that can be processed
and used by other parts of your computer.
▪ Keyboard
▪ Mouse/Trackball
▪ Touchpad
▪ Scanner
▪ Microphone
▪ Digital Cameras
12. OUTPUT DEVICES take information within
your computer and present it to you in a form
that you can understand.
▪ Monitor
▪ Printer
▪ Speakers
▪ Modem
13. Computer is the BEST COMPANION of our
daily life.
▪ Network attached storage
▪ Media Server
▪ Graphics design
▪ On-line banking
▪ Gaming
▪ Social Networking
▪ Knowledge sharing
▪ Science