Overview of the Computer System

 

Overview of the Computer System

 Monitor
A monitor is a computer display that is like a TV monitor. A computer monitor image is made up
of pixels (dots). In general, the higher the resolution, the better the image. The smaller the dots
pitch (typically from 0.25 mm to 0.31 mm), the better the image. The different types of display
screens are:
• Standard television set
An ordinary home televisionthat can be used for computer output.
• Standard computer monitors
These monitors have better resolution than TV monitors. Some are
flat screens.
• Liquid Crystal Displays (LCD)
These screens are made up of two glass plates with liquid in between.

Keyboard
The keyboard is the main input device for text and commands. The computer keyboard uses the
same key arrangement as typewriters. It also contain standard function keys, such as the
escape, cursor movement and control keys.
Keyboards come with three (3) different types of port such as:
• Serial port
• PS/2 port
• USB port.

Wireless keyboard              Multimedia keyboard


Speakers
Speakers give out information in the form of sound. Computer speakers range widely in quality
and price. Computer speakers are typically packaged with computer systems in small plastic
boxes with mediocre sound quality. The internal amplifiers requires an external power source,
known as 'wall-wart'.
Mouse
A mouse is an input device used to controls the movement of the cursor or pointer on a display
screen. It has right click, left click and double click to function
An optical mouse uses camera technology and digital processing to compare and track the
position of the mouse, rather than a ball and rollers used on PS/2 port mouse. A small LED
(light-emitting diode) provides light underneath the mouse, helping to highlight slight differences
in the surface underneath the mouse. It does not require maintenance or regular cleaning.
(source : http://images.search.yahoo.com)
USB port optical mouse
PS/2 port mouse
Cordless optical mouse