2. OBJECTIVES
Identify and describe the most common
output devices.
Identify and describe the most common input
devices.
Identify and describe storage devices.
Identify and describe how input and output
devices are connected to the computer.
3. INPUT AND OUTPUT DEVICES
Input devices enable a user to input data and
commands to the computer to be processed.
Output devices enable the computer to give
or show you the results of its processing.
Some devices can perform both input and
output operations.
4. INPUT DEVICES- KEYBOARD
The Keyboard
- is the most widely used input device.
-As you press keys on the keyboard, an
electrical signal representing that key is sent
to the computer.
-Keyboards are divided into sections.
6. INPUT DEVICES- KEYBOARD
Typewriter keys: The standard alphabetic and
numeric characters you would find on a
typewriter.
Function keys: Special keys that perform some
specific function for the application being run.
Numeric keypad: Used for mathematical
operations.
Directional keys: Used to move the cursor
around the screen.
7. INPUT DEVICES- MOUSE
The mouse is a
pointing device that
rolls around on a flat
surface and controls
the location of the
pointer on the
screen.
8. INPUT DEVICES- MOUSE
The mouse performs the following
functions:
– Pointing: Placing the on-screen pointer at
a specific place
– Clicking: Pressing and releasing the
mouse button
9. INPUT DEVICES- MOUSE
– Dragging: Holding down the mouse
button and dragging an object to a new
location by dragging the mouse
– Double-clicking: Pressing and releasing
the mouse button twice very quickly
– Right-clicking: Pressing the right
mouse button
10. Other Pointing Devices
Other devices that control the on-screen
pointer:
-Trackball: This is like a mouse turned upside
down. You roll a ball around with your fingers
to control the location of the pointer.
-These frequently are found on notebook
computers.
12. Other Pointing Devices (cont.)
-Joystick and wheel: Joysticks consist of a
metal or plastic handle mounted on a base
that you can move in any direction to move
the pointer or other object.
-These typically are used for video games.
-Most have buttons that can be pushed
or clicked to control input/output.
14. Other Pointing Devices (cont.)
-Pointing stick: A pressure-sensitive device
that resembles a pencil eraser; found mostly
on notebook computers
-Graphics tablet: A flat drawing surface
connected to the computer
-The user draws on the surface, and the
figures or writing on the tablet can be input
to the computer for processing
16. Other Pointing Devices (cont.)
-Touch display: Screens that contain pictures
or shapes that the user can press to input
that data
-Stylus/digital pen: Used with mobile devices
to input data
-Touchpad: Used mostly in laptop/notebook
computers
20. Other Pointing Devices (cont.)
-Audio/voice input: Inputting sound and/or
voice.
– These usually require a microphone and
special voice recognition software to be
installed on the computer.
22. Other Pointing Devices (cont.)
Scanners: Devices that can convert a
graphical image into a digital image and input
it to the computer
– Types of scanners include
Image scanners for scanning images and text
Bar code scanners to read product bar codes
Magnetic scanners to read the magnetic strip
on a credit card
24. Other Pointing Devices (cont.)
Digital cameras: Used to take pictures and
store them on a magnetic disk instead of on
film
– Their images can be input directly into the
computer.
Video input: Input from a camcorder or VCR
using video capture cards
26. Other Pointing Devices (cont.)
Biometric input: Uses
fingerprint, face,
handwriting, and
voice for identification
27. Magnetic Storage Devices
Floppy disks: Small, portable
disks that hold a
limited amount of data
Hard disks: Large-capacity
and fast-access storage devices
28. Magnetic Storage Devices (cont.)
Zip disks: Auxiliary storage devices
that can hold large quantities
of data and can be portable
Magnetic tape drives: Used
for making system backups and
storing large quantities of data
29. Optical Storage Devices
CD-DA: Audio CD
CD-R: This drive allows you to read and to write to a
compact disk.
CD-ROM: Can hold large amounts of data, but is
read-only access.
CD-RW: Can be written on several times
DVD-ROM: Read-only DVD format
DVD-R: Similar to CD, but holds more data; read-
only
DVD-RW: Can be written on several times
PhotoCD: Used for storing digital photographs on a
CD
30. Solid-State Storage Media
Non-volatile removable media
Miniature mobile media
– Uses integrated circuits
USB flash drive
– Connects to the computer
via a USB port
31. Caring for Storage Media
To safeguard your data from damage, follow
these tips when dealing with removable
media:
– Keep away from magnetic fields.
– Avoid extreme temperatures.
– Never try to disassemble the case.
– Remove media from drive when not being
used.
32. Caring for Storage Media (cont.)
Tips for dealing with storage media (cont.)
– Write-protect important data.
– Hold optical disks at their edges.
– Never remove the media from the drive if
the access light is on.
– Keep disks in a sturdy case when
transporting them.
33. Output Devices—Monitors
Monitors are used to display video output to
a user.
Monitors may be monochromatic or color.
– Monochromatic monitors display output in
a single-color display.
35. Output Devices—Printers
Printers are used to create a hard copy of a
document or image.
– Printers vary by speed, quality, and price
The most popular types of printers are
– Laser: Produce images using the same
techniques as copier machines
36. Output Devices—Printers (cont.)
– Ink jet: Use fine nozzles to spray ink onto
the page as the paper passes through
– Dot matrix: Work similarly to a typewriter
in that ink is transferred to the paper by
some part of the printer striking a ribbon to
transfer an image
38. Other Types of Output Devices
Speakers and headsets
Fax machines and fax modems
Multifunctional devices
Data projectors
39. Connecting I/O Devices to the
Computer
Input and output devices must be connected to
the computer before they can be used.
Connecting I/O devices to the computer:
– Plug the device into an existing socket or port on
the back of the computer.
– Install an expansion card with the port you need
included on the back of the card.
– Connect wirelessly.
40. Summary
Input devices enable you to input data and
commands into the computer.
The most common input devices are the keyboard
and mouse.
Other types of input devices include trackball,
joystick and wheel, pointing stick, graphics tablet,
touch display screen, stylus, voice recognition
devices, touchpad, scanner, digital camera, video
input, and biometric input.
41. Summary (cont.)
To maintain a permanent copy of data,
you should store it on some type of
storage medium.
The three categories of storage media are
magnetic storage, optical storage, and
solid-state storage.
Monitors and printers are examples of
output devices.
42. Summary (cont.)
Monitors produce soft copy.
Printers are used to produce a paper or
hard copy of the processed result.
Criteria for selecting a printer include
speed, print quality, and cost.
Input and output devices must be
physically connected to the computer.
43. Summary (cont.)
Some input devices communicate with the
computer through a physical connection.
Wireless devices communicate with the
computer through infrared or radio waves.