Disadvantage

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•Keyboard
A keyboard is typewriter keyboard,
which uses an arrangement of
buttons or keys, to act as mechanical
levers or electronic switches.
ADVANTAGE of keyboard,
Reliable for data input of text and
numbers.
DISADVANTAGE of keyboard,
Users may be slow for not very
accurate typists.
•Numeric Keypads
A Numeric Keypad, numpad or tenkey
for short, is the small, palm-sized,
seventeen key section of a computer
keyboard, usually on the very far right.
ADVANTAGE of numeric keypads,
Easier to use with just one hand.
DISADVANTAGE of numeric keypads,
As meaning of keys alter they can become
difficult to use quickly.
•Pointing devices
 A pointing device is an input interface
(specifically a human interface device) that
allows a user to input spatial (i.e., continuous
and multi-dimensional) data to a computer.
 ADVANTAGE of pointing devices,
Move cursor around the screen faster than using
keystrokes.
 DISADVANTAGE of pointing devices,
They are useless on command driven interfaces.
Tracker
ball
mouse
Touch pad
•Remote Controls

A remote control is a component of an
electronics device, most commonly a
television set, used for operating the device
wirelessly from a short line-of-sight distance.

ADVANTAGE of remote control,
Each function can have its own button making
them very simple to use.

DISADVANTAGE of remote control,
Only advanced models can be have the
buttons reprogrammed so they cannot be used
to control anything other than the device they
were designed for.
•Joysticks

A joystick is an input device consisting of a
stick that pivots on a base and reports its angle
or direction to the device it is controlling.

ADVANTAGE of joysticks,
Easy to learn to use. Very simple design so
they can be inexpensive.

DISADVANTAGE of joysticks,
Control can be a bit crude as the directions in
simple joysticks are limited to forward,
backwards, left and right. Better models offer
diagonal movement or better.
•Touch Screens

A touch screen is an electronic visual display
that can detect the presence and location of a
touch within the display area.

ADVANTAGE of touch screens,
Big screen is ideal for web browsing, picture
and movies.

DISADVANTAGE of touch screens,
Big screen leads to low battery life.
•Magnetic Stripe Readers

A magnetic stripe card is a type of card
capable of storing data by modifying the
magnetism of tiny iron-based magnetic
particles on a band of magnetic material on
the card.

ADVANTAGE of magnetic stripe readers,
Simple to use and cheap to produce. The data
can be altered if necessary

DISADVANTAGE of magnetic stripe readers,
Very limited storage capacity. Data easily
destroyed by strong magnetic fields.
•Chip Readers

A smart card, chip card, or integrated circuit
card (ICC), is any pocket-sized card with
embedded integrated circuits.

ADVANTAGE of chip readers,
It enables more data to be stored on the card
and also enables the personal identification
number (PIN) entered by the user to be
checked against the information held in the
chip.

DISADVANTAGE of chip readers,
So easy to disappear.
•Scanners

A device that optically scans images, printed
text, handwriting, or an object, and converts it
to a digital image.

ADVANTAGE of scanners,
Flat-bed scanners are very accurate and can
produce images with a far higher resolution
than a digital camera.

DISADVANTAGE of scanners,
Can produce very large image files which need
a lot of computer memory to view and edit.
•Digital camera

A digital camera (or digicam) is a camera that
takes video or still photographs, or both,
digitally by recording images via an electronic
image sensor.

ADVANTAGE of digital cameras,
No film is needed and there are no film
developing costs.

DISADVANTAGE of digital cameras,
Images often have to be compressed to avoid
using up too much expensive memory.
•Microphones

A microphone (pronounced as mic or mike) is
an acoustic-to-electric transducer or sensor
that converts sound into an electrical signal.

ADVANTAGE of microphones,
Voice recognition software can be used to
convert your voice into text or to control menu
options on a phone system.

DISADVANTAGE of microphones,
Voice commands can be difficult to recognize
by the software.
•Sensor

A device that measures a physical quantity and
converts it into a signal which can be read by
an observer or by an instrument.

ADVANTAGE of sensor,
Measurements are always taken at the right
time.

DISADVANTAGE of sensor,
Expensive when compared to traditional
devices e.g. thermometers.
•Graphics Tablet

A graphics tablet (or digitizing tablet, graphics
pad, drawing tablet is a computer input device
that allows one to hand-draw images and
graphics, similar to the way one draws images
with a pencil and paper.

ADVANTAGE of graphics tablet,
Direct input of user-preferred graphics into
the computer.

DISADVANTAGE of graphics tablet,
Configuration and compatibility can be an
issue.
•MICR

Magnetic Ink Character Recognition, or MICR,
is a character recognition technology used
primarily by the banking industry to facilitate
the processing of cheques.

ADVANTAGE of MICR,
The error rate for reading MICR characters is
small as compared to other character
recognition systems.

DISADVANTAGE OF MICR,
MICR readers are expensive and capable of
recognizing only MICR fronts written in a
specific format.
•OMR

Optical Mark Recognition (also called Optical
Mark Reading and OMR) is the process of
capturing human-marked data from document
forms such as surveys and tests.

ADVANTAGE of OMR,
The user can only make marks and cannot
write any information.

DISADVANTAGE OF OMR,
Document for mark reader are complicated to
design.
•OCR

A mechanical or electronic translation of
scanned images of handwritten, typewritten or
printed text into machine-encoded text.

ADVANTAGE of OCR,
Human-readable

DISADVANTAGE of OCR,
Not accurate, because it first compares to a
list then the one closest is chosen.
•Barcode Readers

An electronic device for reading printed
barcodes. Like a flatbed scanner, it consists of
a light source, a lens and a light sensor
translating optical impulses into electrical
ones.

ADVANTAGE of barcode readers,
Bar codes are a fast and reliable method of
inputting data. They can be read even when
they are on curved surfaces or upside down
and the check digit that is included in the code
makes it reasonably good at rejecting errors.

DISADVANTAGE of barcode readers,
Input is limited to a number code. An extra
layer of packaging is needed for multi-pack
goods because they need a different barcode
to the one on the individual items.
•Video Cameras

A camera used for electronic motion picture
acquisition, initially developed by the
television industry but now common in other
applications as well

ADVANTAGE of video cameras,
Makes video sequences available for editing
by a computer.

DISADVANTAGE of video cameras,
Video images take up a lot of main memory in
a computer, or disk space.
•Webcams

A video capture device that is connected to a
computer or computer network, often using a
USB port or, if connected to a network,
internet or Wi-Fi.

ADVANTAGE of webcams,
Can record what is put into and taken out of a
till, to deter theft.

DISADVANTAGE of webcams,
Images can be poor quality.
•Light Pens
 A computer input device in the form of a lightsensitive wand used in conjunction with a
computer's CRT TV set or monitor.

ADVANTAGE of light pens,
Easy to use.

DISADVANTAGE of light pens,
Easily damaged.
Monitor (CRT)
 Monitor is an object intended to
be used safely by more than one
thread.
 ADVANTAGE of CRT monitor
Produce a very dark black and
the highest contrast levels
normally available.
 DISADVANTAGE of CRT
monitor They are large, heavy,
and bulky. They consume a lot of
electricity and produce a lot of
heat.
Monitor(TFT)
 Monitor is an object intended to
be used safely by more than one
thread.
 ADVANTAGE of TFT monitor
smaller sized therefore consume
less space.
 DISADVANTAGE of TFT monitor
Fewer glares produced and
radiation is much less compared
to CRT Monitors.
Projectors
 Projectors are hardware
device that enables an image,
such as a computer screen, to
be projected onto a flat
surface.
 Advantage of projectors
Enables a lot of people to be
able to see something even
from a distance .
 Disadvantage of projectors
Image quality may not be as
good when projected.
Printers (laser)
 A printer is a peripheral
which produces a text
and/or graphics) of
documents stored in
electronic form.
 Advantage of laser
printer color printing is
possible , Print quality is
good.
 Disadvantage of laser
prints emerge from the
printer slightly wet and
may need time to dry.
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Printers (ink jet)
 A printer is a peripheral
which produces a text
and/or graphics) of
documents stored in
electronic form.
 Advantage of ink jet printer
are less expensive, you can
do color printing with ink
jet.
 Disadvantage of ink jet
printer the speed of printing
is less if the cartridges got
used they are very costly.
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Printers (dot matrix)
 A printer is a peripheral
which produces a text
and/or graphics) of
documents stored in
electronic form.
 Advantage of dot matrix
printer low purchase cost ,
Rugged and low repair cost.
 Disadvantage of dot
matrix printer Not all can
do color, Color looks faded
and streaky.
Plotters
 A plotter is a computer
printing device for printing
vector graphics.
 Advantage of plotter are that
because they are a vector
graphics printer, meaning they
can only print lines and
minimum curves, they are
great for printing blueprints
and maps.
 Disadvantage of plotter they
aren't designed for printing
ordinary photographs so you
would be disappointed with
the quality if you tried.
Speakers
 Speakers are hardware devices
connected to a computer's
sound card that outputs
sounds generated by the card.
 ADVANTAGE of speaker
They're very simple to operate.
 Disadvantage of speaker They
can take up a fair amount of
desk-space, compared to
headphones.
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