4. What Is Input?
• What is input?
4
Ø Input device is
any hardware
component used
to enter data or
instructions
Ø Data or instructions entered into memory
of computer
5. What Is Input?
• What are the two types of input?
5
§ Unprocessed text,
numbers, images,
audio, and video
Ø Instructions
§ Programs
§ Commands
§ User responses
Ø Data
6. The Keyboard
• How is the keyboard divided?
6
Ø Typing area
Ø Numeric keypad
Ø Function keys, special
keys that issue
commands
7. The Keyboard
• What is a cordless keyboard?
7
Ø Communicate with a receiver attached to a port on the
system unit
8. Pointing Devices
• What is a mouse?
8
Ø Pointing device that fits under palm of hand
§ Pointing device controls
movement of pointer, also
called mouse pointer
Ø Mechanical mouse
has rubber or metal
ball on underside
mouse buttons
wheel
button
mouse pad
ball
9. Pointing Devices
•What is an optical mouse?
9
Ø No moving mechanical
parts inside
Ø Senses light to detect
mouse’s movement
Ø More precise than
mechanical mouse
Ø Connects using a
cable, or wireless
10. Other Pointing Devices
• What is a trackball?
10
Ø Stationary pointing device
with a ball on its top
Ø To move pointer, rotate ball
with thumb, fingers, or palm
of hand
11. Other Pointing Devices
•What are a touchpad and a
pointing stick?
11
Ø Touchpad is small, flat,
rectangular pointing device
sensitive to pressure and motion
Ø Pointing stick is pointing device
shaped like pencil eraser
positioned between keys on
keyboard
12. Other Pointing Devices
• What are a joystick and a wheel?
12
Ø Joystick is vertical
lever mounted
on a base
Ø Wheel is
steering-wheel-type
input device
§ Pedal simulates
car brakes and
accelerator
13. Other Pointing Devices
• What is a light pen?
13
Ø Handheld input device
that can detect light
§ Press light pen against
screen surface and then
press button on pen
14. Other Pointing Devices
• What is a touch screen?
14
Ø Touch areas of screen with
finger
Ø Often used with kiosks
15. Other Pointing Devices
• What is a stylus?
15
Ø Looks like a ballpoint pen, but
uses pressure to write text and
draw lines
Ø Used with graphics tablets,
flat electronic boards
16. Other Pointing Devices
• Where is a stylus used?
16
Ø Some desktop computers
Ø Many mobile computers
and devices
§ Handwriting recognition
software translates
handwriting into characters
that computer can process
17. Voice Input
• How does voice recognition work?
17
Step 2. An analog-to-digital converter (ADC) translates
sound waves into digital measurements computer can
process. Measurements include pitch, volume, silences, and
phonemes. Phonemes are sound units such as aw and guh.
10010111010110101100001101
Step 3. Software compares
spoken measurements with those
in its database to find a match or
list of possible matches.
Matches
Step 4. To narrow a list down, software presents user with
a list of choices or uses a natural language component to
predict most likely match. User may correct any selection
made by software.
Natural Language Engine
Step 1. A user dictates text into a microphone.
18. Voice Input
•What is a MIDI (musical instrument
digital interface)?
18
Ø External device, such as
electronic piano keyboard, to
input music and sound effects
19. PDAs, Tablet PCs, and Smart
Phones
•How is a data
entered into a
PDA?
19
20. PDAs, Tablet PCs, and Smart
Phones
•What is a portable
keyboard?
20
Ø Full-sized keyboard you
conveniently attach to
and remove from PDA
22. PDAs, Tablet PCs, and Smart
Phones
• What is a smart
phone?
22
Ø Users can input and send
text messages, graphics,
pictures, video clips, and
sound files
Ø Many have a built-in or
attachable camera
23. Digital Cameras
• What is a digital camera?
23
Ø Allows you to take
digital pictures
Ø Images viewable
immediately on
camera
§ Download to
computer
§ Post pictures
to Web
24. Video Input
• What is video input?
24
Ø Process of entering full-motion images
into computer
Ø Video capture card is
adapter card that converts
analog video signal into
digital signal that
computer can use
Ø Digital video (DV)
camera records video as
digital signals
25. Video Input
• What are a PC video camera and a Web cam?
25
Ø PC video camerac—cDV camera used to capture video
and still images, and to make
video telephone calls on Internet
§ Also called PC camera
Ø Web camc—cvideo camera
whose output displays on
a Web page
26. Video Input
• What is video conferencing?
26
§ Whiteboard is
another window on
screen that can
display notes and
drawings
simultaneously on
all participants’
screens
Ø Two or more geographically separated people
who use network on Internet to transmit
audio and video data
27. Scanners and Reading
Devices
• What is a scanner?
27
Flatbed
Pen or
Handheld
Sheet-fed
Drum
Ø Light-sensing device that
reads printed text and
graphics
§ Used for image processing,
converting paper documents
into electronic images
28. Scanners and Reading
Devices
• What is an optical reader?
28
§ Optical character recognition
(OCR) reads characters in
OCR font
§ Optical mark recognition
(OMR) reads hand-drawn pencil
marks, such as small circles
§ Bar code scanner
Ø Device that uses light source to read characters, marks,
and codes and then converts them into digital data
30. Scanners and Reading
Devices
• What is a data collection device?
30
Ø Obtains data directly at location where transaction
or event takes place
Ø Transmits data over
network
or Internet
31. Terminals
• What is a point of sale (POS) terminal?
31
Ø Records purchases,
processes credit or debit
cards, and updates inventory
§ Swipe credit or debit card
through card readerc—creads
customer’s personal data
from magnetic strip
32. Terminals
• What is an automated teller machine (ATM)?
32
Ø Self-service banking machine that connects to a host
computer through a network
33. Terminals
• What is a smart display?
33
Ø Thin monitor that detaches from computer to function
as portable wireless touch screen
34. Biometric Input
• What is biometrics?
34
Ø Authenticates person’s identity by
verifying personal characteristic
§ Fingerprint scanner captures
curves and indentations of
fingerprint
§ Hand geometry system measures
shape and size of person’s hand
35. Biometric Input
• What are examples of biometric technology?
35
Ø Voice verification system compares live
speech with stored voice pattern
Ø Signature verification system recognizes
shape of signature
Ø Iris recognition system reads
patterns in blood vessels in back
of eye
§ Biometric data is sometimes stored
on smart card, which stores
personal data on microprocessor
embedded in card
36. • Source : Shelly, Gary B. Discovering
Computers (2004/2005/2006). Thomson
Course Technology. PPT for Chapter 5.
36
