This document discusses input and output devices for computers. It describes keyboards, mice, and other pointing devices as common input devices for entering data, software, and commands. It also discusses monitors, printers, and other devices as output mechanisms for displaying and printing processed data in text, graphic, audio, and video formats. The mouse is highlighted as the most widely used pointing device for selecting on-screen items.

1. Devices

2.  Input
 Input is any data entered into the computer’s
memory.
 Types of input include:
◦ Data – Unorganized information (words, numbers,
images, or sounds) that the computer converts to
meaningful information
◦ Software – Programs transferred from storage
devices to the computer’s memory
◦ Commands – Instructions that tell the computer
what to do

3.  Input Devices: Giving Commands
Keyboard
Mouse
Other Pointing Devices

4.  Keyboards
◦ Traditional keyboards
 Flexible keyboards
 Wireless keyboards
 The keyboard allows the computer user to
enter words, numbers, punctuation, symbols,
and special function commands into the
computer’s memory.
Flexible Keyboard
Wireless Keyboard

5.  Mouse
◦ Mechanical
◦ Cordless
or wireless
◦
 Touch Screen
 Light Pen

6.  The mouse is the most widely used pointing
device.
 A mouse is palm sized.
 As the mouse is moved, its movements are
mirrored by the on-screen pointer.
 Cordless mouse – Uses infrared signals to
connect to the computer’s IrDA port; it
must be within sight of the receiving port

7. What is Output?
Output is data that has been
processed into a useful form.

8.  Processed data or information
 Types of output
◦ Text
◦ Graphics
◦ Audio & video
 Output devices
◦ Monitors
◦ Printers

10.  Known as screens or display screens
 Output referred to as soft copy
 Information on display device sometimes
called soft copy
 Types of monitors:
◦ Cathode-ray tube (CRT)
◦ Liquid Crystal Display (LCD or flat-panel)
LCD
CRT

11. 
Monitor
This is the most common output device.

12. ◦ Data projectors
◦ High-definition television (HDTV)

13.  What is a printer?
 Output device that produces text and graphics on
paper
 Result is hard copy, or printout
 Features
◦ Color capability
◦ Speed

14.  Ink-jet printer
 Laser printer
◦ Personal laser printers
◦ Shared laser printers
 Other printers
◦ Plotters
◦ Photo printers

15.  Inkjet printer, also called a bubble-jet,
makes characters by inserting dots of ink
onto paper
 Letter-quality printouts
 Cost of printer is inexpensive but ink is
costly
Inkjet Printer

16.  Laser printer works like a copier
 Quality determined by dots per inch (dpi)
produced
 Color printers available
 Expensive initial costs but cheaper to
operate per page
Laser Printer

17.  A plotter is a printer that uses a pen that
moves over a large revolving sheet of paper.
 It is used in engineering, drafting, map
making, and seismology.
Plotter Printer

18.  Translates audio information into sounds that
people can understand
 Computer component that produces music, speech, or
other sounds
 Common devices
◦ Speakers
◦ Headphones

19. Thanks