- The monitor is a visual display
device to present output information
in the form of text, graphics, or
video on the monitor screen.
- There are two kinds of monitor; the
flat panel or LCD (Liquid Crystal
Display) monitor and the older CRT
(Cathode Ray Tube) models.
CRT (Cathode Ray Tube)
- It is basically a vacuum tube with
an electron gun and a fluorescent
screen. A coating of red, green and
blue are used to form images in the
form of light emitted from the
TFT LCD (Thin Film Transistor Liquid
- LCDs are thin, flat display device
made of color pixels arrayed in front
of a light source (backlight) or
reflector. The advantage of LCD
monitors is less space, low power
and low radiation.
- It is a computer device that
produces a permanent copy on paper
of information from the computer.
There are several kinds of printers:
ink jet, dot-matrix and laser jet
DOT MATRIX PRINTER
- Prints by hammering or striking an ink-
soaked cloth ribbon against a paper. The
advantage of this kind of printer is that it
can easily create carbon copies because of
the impact action of the printing process.
The cost per page of printing is relatively
INK JET PRINTER
- Operates by propelling or spraying
different sizes of very small and
precise amount of ink onto a paper
or other media. Printing quality of
this printer is better than the dot
INK JET PRINTER
- The ink comes form a cartridge of
liquid ink and this printer is simply
black and white or in full color.
LASER JET PRINTER
- It produces high quality prints or
graphics on paper. Color and black and
white printing is available. It is based on
the principle of electrostatic printing and
photography wherein the source of ink is
- Produce prints on thermal paper by
selective heating wherein heated
areas turns black creating an image.
It is mostly used in groceries and
department stores. They print faster
and quieter than dot matrix.
- It is an output device for sounds
music, audio from movies and
computer alerts are heard from this
device. There are several speaker
system for computer, from 2 piece
simple system to as man as 5 and