4. INTRODUCTION
The term computer is derived from the word compute. A computer is an
eletronic device that takes the data and instruction as an input from the
user, processes data, and the 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.
5. Computer is classified into several categories depending
on their computing ability and processing speed. These
incude
* microcomputer
* minicomputer
*mainframe computer
*supercomputer
6. microcomputer
The term microcomputer is generally
synonymous with personal computer, or that
depends on a microprocessor.
Microcomputers are designed to be used by
individuals, wether in the form of PCs,
workstation 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.
7. MINICOMPUTER
A minicomputer is a medium sized
computer that is more powerful than the
microcomputer. An important distinction
between the microcomputer and a
minicomputer that is 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 system among
research and business organizations today.
They are more expensive than computer.
8. MAINFRAME
COMPUTER
The mainframes are high-performance
computers with large amounts of
memory and processors that process
billions of simple calculations and
transactions in real time. The mainframe
is critical to commercial databases,
transaction servers, and applications that
require high resiliency, security, and
agility.
9. SUPERCOMPUTER
Supercomputer are the most
powerful and expensive
computers available.
Supercomputer are primarily
used for complex scientific
application,which need a higher
level of processing. Some of these
application include weather
forcasting, climate research,
molecular modeling used for
chemical compounds, aeroplane
simulation and nuclear fusion
research.
10. HARDWARE
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 reffered to as components,
while external hardware devices are usually called peripherals.Together, they all
fall under the category of computer hardware.
11. SOFTWARE
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 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.
13. OUTPUT DEVICES
Output devices take
information within
your computer and
present it to you in a
form that you can
understand.
14. USAGE OF COMPUTER
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