In this chapter students will learn about:
  • Input devices:
  • The uses of each device
  • The advantages of each device
  • The disadvantages of each device
  • Output devices:
  • The uses of each device
  • The advantages of each device
  • The disadvantages of each device
  • Control applications and the uses of each device.

Computer Input Devices

Entering text into a word processing document. Applications where text has to
be created rather than copied
Numeric keypad
Applications where only numeric data is to be entered. Inserting personal
identification number (PIN) for Chip and PIN credit/debit cards, or when using an
ATM machine to withdraw money or check a bank balance
Pointing devices
All applications which require selection from a graphical user interface. For
example: the selection of data from a set list or menu
In most PCs
On laptop computers
For use by people with limited motor skills e.g. young children or people with
Using remote control devices to operate TVs, video players/recorders, DVD
players/recorders, satellite receivers, HiFi music systems, data or multimedia
Used by a pilot to fly an aeroplane or flight simulator. Used in car driving
simulators and for playing games
Touch screen
Selecting from a limited list of options e.g. certain POS uses such as cafes, tourist
information kiosks, public transport enquiries. May be used for handwriting
recognition in a PDA or Tablet PC
Magnetic stripe reader
At POS terminals, ATMs and in security applications
Smart card
Payment cards, ID cards, door control systems, public transport tickets
Entering hard copy images into a computer
Digital camera
Taking photographs for input to computers, for input to photo printers
Recording of voices for presentation software
MIDI instrument
Recording a performance directly onto a computer as a MIDI file
Temperature sensor
Automatic washing machines, automatic cookers, central heating controllers,
computer-controlled greenhouses, scientific experiments and environmental
Light sensor
Computer-controlled greenhouses, burglar alarm systems, robotics, production
line control, scientific experiments and environmental monitoring
Graphics tablet
Inputting freehand drawings or retouch photographs
Magnet Ink Character Reader(MICR)
Inputting magnetic characters, such as those found on bank cheques
Optical Mark Reader(OMR)
Inputting pencil marks on a form such as a school register, candidate exam
answers, any application involving input of a choice of options
Optical Character Reader (OCR)
Inputting text to a computer ready for processing by another software package
such as word processors, spreadsheets or databases
Bar code reader
Inputting code numbers from products at a POS terminal, library books and
membership numbers
Video camera
Inputting moving pictures, often pre-recorded, into a computer
Vieo digitiser
Inputting video from an analogue source (for example television or video camera)
Web cam
Inputting moving pictures from a fixed position into a computer
Light pen
Where desktop space is limited, it is used instead of a mouse or for drawing
applications where a graphics tablet might be too big

Computer Output Devices

CRT monitor
Applications where space is not a problem. Applications where more than one
user may need to view screen simultaneously such as in design use, e.g. when
several designers may need to offer suggestions on a prototype
TFT monitor
Applications where space is limited such as small offices. Applications where
only one person needs to view the screen such as individual workstations
Laser printer
Applications which require low noise and low chemical emissions, e.g. most
networked systems. Applications which require rapid, high quality and high
volumes of output, e.g. most offices and schools
Inkjet printer
Applications which require portability and low volume output, where changing
cartridges is not an issue e.g. small offices and stand alone systems. Applications
which require very high quality output and where speed is not an issue, e.g.
digital camera applications
3D inkjet printer
CAD/CAM applications where 3D designs are made by layering of resin powder
Dot matrix printer
Applications where noise is not an issue and copies have to be made, e.g.
industrial environments (multipart forms, continuous stationery, labels etc.), car
sales and repair companies, manufacturing sites
Graph plotter
CAD applications, particularly where large printouts are required such as A0
Any application which requires sound to be output such as multimedia
presentations and websites including encyclopaedias. Applications that require
musical output such as playing of music CDs and DVD films

Control devices in control applications

Automatic washing machines, automatic cookers, central heating controllers,
computer-controlled greenhouses, microwave ovens, robotics, production line
Automatic cookers, microwave ovens
Automatic washing machines, automatic cookers, central heating controllers,
computer-controlled greenhouses
Computer-controlled greenhouses

Computer input devices

Computer output devices

Computer Control devices