Discovering Computers Fundamentals,
2012 Edition
Chapter Five: Input
Objectives Overview
Identify the keys and buttons
commonly found on desktop
computer keyboards, and
describe how keyboards for
mobile computers and devices
differ from desktop computer
keyboards
Describe different mouse types
Describe various types of touch
screens and explain how a
touch-sensitive pad works
Describe various types of pen
input
See Page 187
for Detailed Objectives
2
Objectives Overview
Explain other types of
input
Explain the characteristics
of LCD monitors, LCD
screens, and CRT monitors
Identify the purpose and
features of speakers,
headphones, and earbuds; data projectors; and
interactive whiteboards
See Page 187
for Detailed Objectives
Summarize the various
types of printers
Identify input and output
options for physically
challenged users
3
What Is Input?
• Input is any data and instructions entered
into the memory of a computer
Pages 188– 189
Figure 5-1
4
What Is Input?
An input device
is any hardware
component that
allows users to
enter data and
instructions into
a computer
Page 188
5
Keyboard and Pointing Devices
• A keyboard is an input device that
contains keys users press to enter data and
instructions into a computer
Page 190
Figure 5-2
6
Keyboard and Pointing Devices
• Keyboards on mobile devices typically are smaller
and/or have fewer keys
• Some phones have predictive text input, which
saves time when entering text using the phone’s
keypad
Page 191
Figure 5-3
7
Page 192
Figures 5-5 – 5-7
• A touchpad is
a small, flat,
rectangular
pointing
device that is
sensitive to
pressure and
motion
Pointing Stick
• A trackball is a
stationary
pointing
device with a
ball on its top
or side
Touchpad
Trackball
Keyboard and Pointing Devices
• A pointing
stick is a
pressuresensitive
pointing
device shaped
like a pencil
eraser that is
positioned
between keys
on a keyboard
8
Touch Screens and Touch-Sensitive
Pads
• A touch screen is a touch-sensitive display
device
Page 193
Figure 5-8
9
Touch Screens and Touch-Sensitive
Pads
Microsoft Surface
Page 193
Figures 5-9 – 5-10
Touch-sensitive pads
10
Pen Input
• With pen input, you touch a stylus or digital
pen on a flat surface to write, draw, or make
selections
Page 194
Figure 5-11
11
Other Types of Input
Page 195
Figure 5-12
12
Other Types of Input
Page 196
Figure 5-13
13
Other Types of Input
Page 197
Figure 5-14
14
Other Types of Input
• Two factors affect the quality of digital camera
photos:
Resolution
Page 198
• Resolution is the
number of horizontal
and vertical pixels in
a display device
• A pixel is the smallest
element in an
electronic display
15
Other Types of Input
• Voice input is the process of entering
input by speaking into a microphone
• Voice recognition is the computer’s
capability of distinguishing spoken words
• Audio input is the process of entering any
sound into the computer
Page 198
16
Other Types of Input
• A video conference is a meeting between two or
more geographically separated people
Page 199
Figures 5-16 – 5-17
17
Other Types of Input
• A flatbed scanner creates a file of the
document in memory
– Works in a manner similar to a copy machine
Page 200
Figure 5-18
18
Other Types of Input
• Optical character recognition (OCR) involves
reading characters from ordinary documents
• A turnaround document is a document you
return to the company that creates and sends it
Page 200
Figure 5-19
19
Other Types of Input
• Optical mark recognition (OMR) reads
hand-drawn marks such as small circles or
rectangles
Page 200
20
Other Types of Input
• A bar code reader,
also called a bar code
scanner uses laser
beams to read bar
codes
Page 201
Figure 5-20
21
Other Types of Input
• RFID (radio frequency identification) uses radio signals to
communicate with a tag placed in or attached to an object
• An RFID reader reads information on the tag via radio
waves
• RFID can track:
Times of
runners in a
marathon
Location of
soldiers
Inventory
Page 201
Employee
wardrobes
Pressure and
temperature
of tires
Airline
baggage
Checked out
library books
Lift tickets of
skiers
Toll payments
22
Other Types of Input
• Magnetic stripe card readers read the
magnetic stripe on the back of cards such
as:
Credit cards
Entertainment cards
Bank cards
Other similar cards
Pages 201
Figure 5-22
23
Other Types of Input
• MICR (magnetic ink character recognition) devices read
text printed with magnetized ink
• An MICR reader converts MICR characters into a form
the computer can process
• Banking industry uses MICR for check processing
Page 202
Figure 5-23
24
Other Types of Input
• Biometrics authenticates a person’s
identity by verifying a personal
characteristic
Fingerprint
reader
Face
recognition
system
Signature
verification
system
Pages 202 - 203
Hand
geometry
system
Iris recognition
system
Voice
verification
system
Retinal
scanners
25
Other Types of Input
iris
recognition
system
fingerprint
reader
Pages 202 – 203
Figures 5-24 – 5-25
26
Other Types of Input
• A terminal is a computer that allows users to
send data to and/or receive information from a
host computer
A POS terminal
records purchases,
processes
payment, and
updates inventory
Pages 204 – 205
Figures 5-26 – 5-28
An automated
teller machine
(ATM) allows users
to access their
bank accounts
A DVD kiosk is a
self-service DVD
rental machine
27
What Is Output?
• Output is data that has been processed
into a useful form
Pages 206 – 207
Figure 5-29
28
Display Devices
• A display device
visually conveys
text, graphics, and
video information
• A monitor is
packaged as a
separate peripheral
– LCD monitor
– Widescreen
Pages 207 – 208
Figure 5-30
29
Display Devices
• Liquid crystal display (LCD) uses a liquid compound to
present information on a display device
Resolution
Response time
Dot pitch
Page 209
Brightness
Contrast ratio
30
Display Devices
• Plasma monitors are display devices that use
gas plasma technology and offer screen sizes up to
150 inches
Page 210
Figure 5-32
31
Display Devices
• A CRT monitor is a desktop monitor that
contains a cathode-ray tube
Page 210
Figure 5-33
32
Printers
• A printer
produces text
and graphics
on a physical
medium
• Before
purchasing a
printer, ask
yourself a
series of
questions
Page 211
Figure 5-34
33
Printers
• A nonimpact printer forms characters
and graphics on a piece of paper without
actually striking the paper
Ink-jet
printers
Photo
printers
Mobile
printers
Page 213
Laser
printers
Plotters
Thermal
printers
Largeformat
printers
34
Printers
• An ink-jet printer forms characters and graphics by
spraying tiny drops of liquid ink onto a piece of paper
– Color or black-and-white
– Printers with a higher dpi (dots per inch) produce a higher quality
output
Page 213
Figure 5-36
35
Printers
A photo printer produces color
photo-lab-quality pictures
• Most use ink-jet technology
• PictBridge allows you to print photos
directly from a digital camera
• Print from a memory card and preview
photos on a built-in LCD screen
Page 214
36
Printers
Highspeed
Blackandwhite
Laser
printer
Highquality
Color
Pages 214 – 215
Figure 5-38
37
Printers
• A multifunction peripheral (MFP) is a
single device that prints, scans, copies, and
in some cases, faxes
– Sometimes called an all-in-one device
Page 215
Figure 5-39
38
Printers
• A thermal printer generates images by
pushing electrically heated pins against the
heat-sensitive paper
Dyesublimation
printer
Pages 215 – 216
Figure 5-40
39
Printers
• Plotters are used to produce high-quality
drawings
• Large-format printers create photorealistic quality color prints on a larger
scale
Page 216
Figure 5-42
40
Printers
• Impact printers form characters and graphics
on a piece of paper by striking a mechanism
against an inked ribbon that physically contacts
the paper
Dot-matrix
printer
Page 217
Line
printer
41
Printers
• A dot-matrix
printer produces
printed images when
tiny wire pins on a
print head
mechanism strike an
inked ribbon
• A line printer
prints an entire line
at a time
Page 217
Figure 5-43
42
Other Output Devices
• An audio output device produces music,
speech, or other sounds
Most computer users attach
speakers to their computers to:
• Generate higher-quality sounds for playing
games
• Interact with multimedia presentations
• Listen to music
• View movies
Page 217
Figure 5-44
43
Other Output Devices
• Headphones are
speakers that cover
or are placed outside
of the ear
• Earbuds (also called
earphones) rest
inside the ear canal
Page 218
44
Other Output Devices
Voice output occurs when you hear a
person’s voice or when the computer
talks to you through the speakers
• Some Web sites dedicate themselves to
providing voice output
• Often works with voice input
• VoIP uses voice output and voice input
Page 218
45
Other Output Devices
• A data projector is
a device that takes
the text and images
displaying on a
computer screen and
projects them on a
larger screen
Page 218
Figure 5-45
46
Other Output Devices
• An interactive
whiteboard is a
touch-sensitive
device, resembling a
dry-erase board, that
displays the image
on a connected
computer screen
Page 218
Figure 5-46
47
Input and Output Devices
for Physically Challenged Users
Head-mounted pointer
Pages 220 – 221
Figures 5-48 – 5-49
Braille printer
48