computer confluence 7 e l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Computer Confluence 7/e PowerPoint Presentation
Download Presentation
Computer Confluence 7/e

Loading in 2 Seconds...

play fullscreen
1 / 87

Computer Confluence 7/e - PowerPoint PPT Presentation


  • 272 Views
  • Uploaded on

Computer Confluence 7/e. Chapter 3 Hardware Basics: Peripherals. © 2006 Prentice-Hall, Inc. Computer Confluence 7/e Chapter 3 Objectives. Input devices and their roles in getting different types of information into the computer Output devices and the ways they make computers more useful

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Computer Confluence 7/e' - victoria


Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
computer confluence 7 e

Computer Confluence 7/e

Chapter 3

Hardware Basics: Peripherals

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 objectives

Computer Confluence 7/eChapter 3Objectives

Input devices and their roles in getting different types of information into the computer

Output devices and the ways they make computers more useful

The functionality of different types of storage devices

The ways the components of a computer system fit together

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 input from person to processor

Computer Confluence 7/eChapter 3Input: From Person to Processor

Keyboard

The most familiar input device

Used to enter letters, numbers and special characters

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 input from person to processor4

Computer Confluence 7/eChapter 3Input: From Person to Processor

Standard keyboard

Ergonomic keyboards

To address possible medical problems

Place the keys at an angels that are easier on your arms and hands.

Wireless keyboard

Folding keyboards

Used with palm-sizedcomputers

One-handed keyboards

Keyboards printed on membranes

that can be rolled or folded like paper.

© 2006 Prentice-Hall, Inc.

slide5

this standard-size fabric keyboard rolls up into a lightweight, compact package that can be tucked into a pocket, or briefcase.

computer confluence 7 e chapter 3 input from person to processor6

Computer Confluence 7/eChapter 3Input: From Person to Processor

Pointing Devices

Mouse

Portable computers :

Touchpad (track pad)

Pointing stick

Trackball

Other pointing devices :

Joystick

Graphics tablet

stylus

Touch screen

© 2006 Prentice-Hall, Inc.

variants of the mouse
Variants of the Mouse
  • Trackballs
    • Upside down mouse
    • Hand rests on the ball
    • User moves the ball
    • Uses little desk space
variants of the mouse8
Track pads

Stationary pointing device

Small plastic rectangle

Finger moves across the pad

Pointer moves with the pointer

Popular on laptops

Variants of the Mouse
variants of the mouse9
Variants of the Mouse

Track point

  • Little joystick on the keyboard
  • Move pointer by moving the joystick
devices for the hand
Pen based input

Tablet PCs, PDA

Pen used to write data

Pen used as a pointer

Handwriting recognition

Devices for the Hand
devices for the hand11
Touch screens

Sensors determine where finger points

Usually presents a menu to users

ATM’s, Malls,

Devices for the hand
computer confluence 7 e chapter 3 input from person to processor12

Computer Confluence 7/eChapter 3Input: From Person to Processor

Reading Tools

Reads marks representing codes specifically designed

for computer input

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 input from person to processor13

Computer Confluence 7/eChapter 3Input: From Person to Processor

Optical-mark readers:

use reflected light to determine the location of pencil marks on standardized test answer sheets and similar forms.

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 input from person to processor14
Computer Confluence 7/eChapter 3Input: From Person to Processor
  • Magnetic-ink character readers : read those odd-shaped numbers printed with magnetic ink on the checks.
  • Bar-code readers

use light to read universal product code (UPC). They are attached to point of sale terminals (POS). These terminals send the scanned information to a mainframe computer => item’s price, calculate total.

  • Radio Frequency Identification Readers :

use radio waves to communicate with Radio Frequency Identification (RFID) tags. When energized by a nearby RFID reader, an RFID tag broadcasts its unique identification number to the reader. which digitizes the information for input into a computer.

slide15
An RFID tag used for electronic toll collection

RFID tags used in libraries: square book tag, round CD/DVD tag and rectangular VHS tag.

computer confluence 7 e chapter 3 input from person to processor16
Computer Confluence 7/eChapter 3Input: From Person to Processor

Because test forms, magnetic ink character, bar codes, and RFID tags were designed to be read by computers, the devices that read them are extremely accurate.

Reading text from books, magazines, and other printed document is more challenging because of the great variety of printed text.

  • Optical character recognition (OCR) is the technology of recognizing individual characters on a printed page, so they can be stored and edited as text.
computer confluence 7 e chapter 3 input from person to processor17
Computer Confluence 7/eChapter 3Input: From Person to Processor

Before a computer can recognize handwriting or printed text, it must first create a digital image of the page that it can store in memory.=>scanner.

A scanner doesn’t actually read or recognize letters and numbers on a page- it just makes a digital “ picture” of the page available to the computer.

slide18
Pen scanners :
      • looks like highlighters.
      • Wireless scanners that can perform character recognition.
  • pen-based computers such as the Tablet PC
    • can work without a keyboard
    • accept input from a stylus
    • handwritten recognition software to translate the user’s handwritten forms into ASCII characters.
slide19
Personal digital assistants (PDAs):
    • are handheld pen computers that serve as organizers, notebooks, communication devices, ….
  • Smart whiteboard:
    • serve as an input device for a PC.
    • board is stored as a digital image on the computer’s disk.
digitizing devices
Digitizing devices
  • Before a computer can recognize hand-written or printed text, a scanner or other input device must digitize the information- convert it into a digital form-.
  • A scanner is an input devicethat can create a digital representation of a printed image.
computer confluence 7 e chapter 3 input from person to processor21

Computer Confluence 7/eChapter 3Input: From Person to Processor

Digitizing the Real World

Scanners capture and digitize printed images

Flatbed

Slide scanner : scan only slides and negatives.

Drum : larger and more expensive.

Sheet-fed : small, portable, and inexpensive.

© 2006 Prentice-Hall, Inc.

slide22
Drum scanner

Slide scanner

Sheet fedscanner

computer confluence 7 e chapter 3 input from person to processor23

Computer Confluence 7/eChapter 3Input: From Person to Processor

Digital camera

Snapshots captured as digital images

Digital images stored as bit patterns on disks or other digital storage media

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 input from person to processor24

Computer Confluence 7/eChapter 3Input: From Person to Processor

Video digitizer

Capture input from a:

Video camera

Video cassette recorder or television

Convert it to a digital signal

Stored in memory and displayed on computer screens

Digital video camera

can send video signals directly into a computer without a video digitizer.

Videoconferencing

People in diverse locations can see and hear each other

Used to conduct long-distance meetings

Video images transmitted through networks

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 input from person to processor25

Computer Confluence 7/eChapter 3Input: From Person to Processor

Audio digitizers

Digitize sounds from

Microphones

Other audio input devices

Digital signals can be

Stored

Further processed with specialized software

A digital signal processing chip compresses the stream of bits before it is transmitted to the CPU

© 2006 Prentice-Hall, Inc.

audiovisual input devices
Audiovisual Input Devices
  • Microphones
    • Used to record speech
    • Speech recognition
      • “Understands” human speech
      • Allows dictation or control of computer
      • Matches spoken sound to known phonemes
      • Enters best match into document
computer confluence 7 e chapter 3 input from person to processor27

Computer Confluence 7/eChapter 3Input: From Person to Processor

Speech recognition software

Converts voice data into words that can be edited and printed

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 input from person to processor28

Computer Confluence 7/eChapter 3Input: From Person to Processor

Sensors

Designed to monitor physical conditions

Temperature, humidity, pressure

Provide data used in:

Robotics

Environmental climate control

Weather forecasting

Medical monitoring

Biofeedback

Scientific research

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 output from pulses to people

Computer Confluence 7/eChapter 3Output: From Pulses to People

Screen Output

A monitor or video display terminal (VDT) displays characters, graphics, photographic images, animation and video

Video adapter —connects the monitor to the computer

a circuit board installed in a slot inside the system unit

VRAM or video memory —a special portion of RAM to hold video images

the amount of VRAM determines the max. resolution and color depth.

the more video memory, the more picture detail is displayed.

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 output from pulses to people30

Computer Confluence 7/eChapter 3Output: From Pulses to People

Monitor size: Measured as a diagonal line across the screen

Resolution: The number of pixels displayed on the screen

Pixels (or picture elements): tiny dots that compose a picture

The higher the resolution, the closer together the dots and the clearer the image.

Image quality is affected by resolution and color depth (or bit depth)

Color depth refers to the number of different colors a monitor displays at one time

© 2006 Prentice-Hall, Inc.

monitors
Monitors
  • Categorized by color output
    • Monochrome
      • One color with black background
    • Grayscale
      • black, white, and Varying degrees of gray
    • Color
      • Display 4 to 16 million colors
computer confluence 7 e chapter 3 output from pulses to people32

Computer Confluence 7/eChapter 3Output: From Pulses to People

Monitor classes

CRTs (cathode-ray tubes)

LCDs (liquid crystal displays) are now more popular

Overhead projection panels

Video projectors

Portable computers

© 2006 Prentice-Hall, Inc.

monitors33
Monitors
  • Cathode Ray Tube (CRT)
    • Electrons fired from the back
    • Electrons excite phosphor to glow
    • Phosphor is arranged in dots called pixels
  • CRT drawbacks
    • Very large
    • Very heavy
    • Use a lot of electricity
flat panel monitors
Flat-panel Monitors
  • Liquid Crystal Display (LCD)
    • Commonly found on laptops
    • Desktop versions exist
    • Solve the problems of CRT
    • Fluorescent lights provide illumination
  • Electro-luminescent displays (ELD)
    • Similar to LCD
    • Uses phosphor to produce light
  • Plasma monitor
    • Gas is excited to produce light
computer confluence 7 e chapter 3 output from pulses to people35

Computer Confluence 7/eChapter 3Output: From Pulses to People

Paper Output

Printers produce paper output or hard copy

Two basic groups of printers:

Impact printers

nonimpact printers

© 2006 Prentice-Hall, Inc.

commonly used printers
Commonly Used Printers
  • Impact printers
      • Line printers
      • Dot-matrix printers
    • Generate output by striking the paper, ribbon, and print hammer together.
    • Uses an inked ribbon
  • Non-impact printers
    • Use methods other than force
    • Tend to be quiet and fast
commonly used printers37
Commonly Used Printers
  • Line printers

- Impact printer

- speedy but noisy

- limited to printing characters.

commonly used printers38
Commonly Used Printers
  • Dot matrix printers
    • Impact printer
    • Used to print to multi-sheet pages
    • Print head strikes inked ribbon
    • Speed measured in characters per second
output from pulses to people
Output: From Pulses to People
  • Non-impact printers
  • Laser printers
    • Laser beam reflected off a rotating drum to create patterns of electrical charges
    • Faster and more expensive than dot matrix printer
    • Produce High-resolution output
    • Color or black and white
    • Print process
      • Laser draws text on page
      • Toner sticks to text
      • Toner melted to page
    • Speed measured in pages per minute
    • Quality expressed as dots per inch
output from pulses to people41
Output: From Pulses to People
  • Non-impact printer
  • Inkjet printers
    • Sprays ink onto paper to produce printed text and graphic images
    • Prints fewer pages/minute than laser printer
    • High-quality color costing less than laser printer
    • Speed measured in pages per minute
    • Quality expressed as dots per inch
high quality printers
High-Quality Printers
  • Photo printers
    • Produces film quality pictures
    • Prints very slow
    • Prints a variety of sizes
computer confluence 7 e chapter 3 output from pulses to people44

Computer Confluence 7/eChapter 3Output: From Pulses to People

Multifunction printer or MFP combines a scanner, printer and a fax modem

Plotter: an automated drawing tool that can produce large, finely scaled engineering blueprints and maps

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 output from pulses to people45

Computer Confluence 7/eChapter 3Output: From Pulses to People

Fax Machines and Fax Modems

Facsimile (fax) machine

Sending:

fax machine scans each page as an image,

converts the image into a series of electronic pulses,

sends those signals over phone lines to another fax.

Receiving:

fax machine uses the signals to reconstruct the image and

print black-and-white facsimiles or copies of the originals

© 2006 Prentice-Hall, Inc.

fax machines and fax modems
Fax Machines and Fax Modems
  • Fax modem:
      • directly from PC to fax machine via modem & phone line
      • translate the document into signals that can be sent over phone wires.
      • Decoded by the receiving fax machine. (remote printer)
      • receive transmission from fax machine (remote scanner)
computer confluence 7 e chapter 3 output from pulses to people47

Computer Confluence 7/eChapter 3Output: From Pulses to People

Output You Can Hear

Sound card

Enables the PC to:

Accept microphone input

Play music and other sound through speakers or headphones

Process sound in a variety of ways

Synthesizers

Specialized circuitry used to produce music, noise electronically.

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 output from pulses to people48

Computer Confluence 7/eChapter 3Output: From Pulses to People

Controlling Other Machines

Output devices take bit patterns and turn them into non-digital movements

Robot arms

Telephone switchboards

Transportation devices

Automated factory equipment

Spacecraft

Force feedback joystick

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 output from pulses to people49

Computer Confluence 7/eChapter 3Output: From Pulses to People

Rules of Thumb: Ergonomics and Health

Choose equipment that’s ergonomically designed

Create a healthy workspace

Build flexibility into your work environment

Rest your eyes

Stretch to loosen tight muscles

Listen to your body

Seek help when you need it

© 2006 Prentice-Hall, Inc.

describing storage devices
Describing Storage Devices
  • Store data when computer is off
  • Two processes
    • Writing data
    • Reading data
describing storage devices51
Describing Storage Devices
  • Storage terms
    • Media is the material storing data
    • Storage devices manage the media
    • Magnetic devices use a magnet
    • Optical devices use lasers
    • Solid-state devices have physical switches
magnetic storage devices
Magnetic Storage Devices
  • Most common form of storage
  • Hard drives, floppy drives, tape
  • All magnetic drives work the same
magnetic storage devices53
Magnetic Storage Devices

Floppy Disk

Hard Disk

Tape

computer confluence 7 e chapter 3 storage devices input meets output

Computer Confluence 7/eChapter 3Storage Devices: Input Meets Output

Magnetic Tape

Can store large amounts of information in a small space at a relatively low cost

Limitation: slow sequential data access : retrieve information by zipping through it in the order in which it was recorded.

Used mainly for backup purposes

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 storage devices input meets output55

Computer Confluence 7/eChapter 3Storage Devices: Input Meets Output

Magnetic Disks

Random data access

information retrieval without regard to the order in which it was recorded.

© 2006 Prentice-Hall, Inc.

magnetic storage devices56
Magnetic Storage Devices
  • Diskettes
    • Also known as floppy disks
    • Read with a disk drive
    • Provide inexpensive, portable storage
    • Slow speed.
    • limited capacity (3 ½ floppy disk holds 1.44 MB)
magnetic storage devices57
Magnetic Storage Devices
  • Hard disks
    • Primary storage device in a computer
    • Non-removable, rigid disks that spin continuously and rapidly
    • 2 or more aluminum platters
    • Each platter has 2 sides
    • Provide much faster access than a floppy disk
    • Data found in 9.5 ms or less
    • Drive capacity greater than 40 GB
magnetic storage devices59
Magnetic Storage Devices
  • Removable high capacity disks
    • Speed of hard disk
    • Portability of floppy disk
    • Several variants have emerged
    • Ex. Zip disks
      • High capacity floppy disk
      • Stores up to 750 MB of data
computer confluence 7 e chapter 3 storage devices input meets output60

Computer Confluence 7/eChapter 3Storage Devices: Input Meets Output

Optical Disks

Use laser beams to read and write bits of information on the disk surface

Not as fast as magnetic hard disks

Massive storage capacity

Very reliable

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 storage devices input meets output61

Computer Confluence 7/eChapter 3Storage Devices: Input Meets Output

CD-ROM

Optical drives that read CD-ROMs

CD-R

WORM media (write-once, read many)

CD-RW

Can read CD-ROMs and write, erase and

rewrite data onto CD-R & CD-RW disks

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 storage devices input meets output62

Computer Confluence 7/eChapter 3Storage Devices: Input Meets Output

DVD (Digital Versatile Disks)

Store & distribute all kinds of data

Hold between 3.8 and 17 gigabytes of information

DVD-ROM drives

Can play DVD movies, read DVD data disks, read

standard CD-ROMs, and play audio CDs

Because they’re read-only, they can’t record data, music, or movies

DVD-RAM drives

Can read, erase, and write data (but not DVD video) on multi-gigabyte

DVD-R (but not CD-R or CD-RW) media

© 2006 Prentice-Hall, Inc.

solid state devices
Solid State Devices
  • Data is stored physically
  • No magnets or laser
  • No moving parts
  • Very fast
computer confluence 7 e chapter 3 storage devices input meets output64

Computer Confluence 7/eChapter 3Storage Devices: Input Meets Output

Solid-State Storage Devices

Flash memory is an erasable memory chip

Sizes range from 16 MB to 1 GB

Compact alternative to disk storage

Contains no moving parts

Designed for specific applications such as storing pictures in digital cameras

Likely to replace disk and tape storage

© 2006 Prentice-Hall, Inc.

storage devices input meets output
Storage Devices: Input Meets Output
  • USB flash drives
    • Can store up to hundreds of megabytes of data.
    • they plug into a computer’s USB port.
computer confluence 7 e chapter 3 computer systems the sum of its parts

Computer Confluence 7/e Chapter 3Computer Systems: The Sum of Its Parts

Personal Computers: basic design classes

Tower systems

Tall, narrow boxes that generally have more expansion slots and bays than other designs

Flat desktop systems

Designed to sit under the monitor like a platform

All-in-one systems (like the iMac)

Combine monitor and system unit into a single housing

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 computer systems the sum of its parts68

Computer Confluence 7/e Chapter 3Computer Systems: The Sum of Its Parts

Portable computers

Include all the essential components, including keyboard and pointing device, in one compact box

© 2006 Prentice-Hall, Inc.

extending the processors power
Extending The Processors Power
  • Standard computer ports
    • Keyboard and mouse ports
    • USB ports
    • Parallel
    • Network
    • Modem
    • Audio
    • Serial
    • Video
computer confluence 7 e chapter 3 computer systems the sum of its parts70

Computer Confluence 7/e Chapter 3Computer Systems: The Sum of Its Parts

Ports and Slots Revisited

The system or motherboard includes several standard ports:

Serial Port for attaching devices that send/receive messages one bit at a time (modems)

Parallel Port for attaching devices that send/receive bits in groups (printers)

Keyboard/Mouse Portfor attaching a keyboard and a mouse

© 2006 Prentice-Hall, Inc.

extending the processors power71
Extending The Processors Power
  • Serial and parallel ports
    • Connect to printers or modems
    • Parallel ports move bits simultaneously
      • Made of 8 – 32 wires
      • Internal busses are parallel
    • Serial ports move one bit
      • Lower data flow than parallel
      • Requires control wires
computer confluence 7 e chapter 3 computer systems the sum of its parts74

Computer Confluence 7/e Chapter 3Computer Systems: The Sum of Its Parts

Other ports are typically included on expansion boards rather than the system board:

Video Port used to plug in a color monitor into the video board

Microphone, speaker, headphone, MIDI ports used to attach sound equipment

LAN port used faster connection to a local-area network (LAN)

© 2006 Prentice-Hall, Inc.

extending the processors power75
Extending The Processors Power
  • SCSI
    • Small Computer System Interface
    • Supports dozens of devices
    • External devices daisy chain
      • allows several peripherals to be strung together and attached to a single port
    • Fast hard drives and CD-ROMs
internal and external drives
Internal and external drives
  • Disks drives generally reside in bays inside the system unit.
  • Some PC have extra bays for additional internal hard drives or removable media
  • External drives can be connected to the system through ports.
  • Some portable enable you to Hot swap devices : remove and replace them without powering down.
extending the processors power78
Extending the Processors Power
  • Expansion slots and boards
    • Allows users to configure the machine
    • Slots allow the addition of new devices
    • Devices are stored on cards
    • Computer must be off before inserting
computer confluence 7 e chapter 3 computer systems the sum of its parts79

Computer Confluence 7/e Chapter 3Computer Systems: The Sum of Its Parts

Expansion Made Easy

With the PC open architecture -

the design that enables you to add expansion cards and peripherals-

and the introduction of new interfaces, you can hot swap devices.

© 2006 Prentice-Hall, Inc.

extending the processors power80
Extending The Processors Power
  • USB
    • Universal Serial Bus
    • Most popular external bus
    • Supports up to 127 devices
      • including keyboard, mice, digital cameras, scanners, and storage devices can be chained together from a single USB port.
    • Hot swappable
    • transmits a hundred times faster than a PC serial port
extending the processors power81
Extending the Processors Power
  • FireWire
    • IEEE 1394
    • can move data between devices at 400 or more megabits per second
    • High speed makes it ideal for data-intensive work like digital video Cameras and video equipment
    • Hot swappable
    • Port is very expensive
  • FireWire 800
    • Recently introduced on high-end Macintosh systems
    • offers 800 Mbps transfer speeds
computer confluence 7 e chapter 3 computer systems the sum of its parts82

Computer Confluence 7/e Chapter 3Computer Systems: The Sum of Its Parts

Putting It All Together

A typical computer system might have several different input, output, and storage peripherals -- the key is compatibility

Networks blur the boundaries between computers

Networked computers may have access to all the peripherals on a system

The computer is, in effect, just a tiny part of a global system of interconnected networks

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 inventing the future tomorrow s peripherals

You can count how many seeds are in the apple,

but not how many apples are in the seed.

—Ken Kesey, author ofOne Flew over the Cuckoo’s Nest

Computer Confluence 7/eChapter 3Inventing the Future: Tomorrow’s Peripherals

Tomorrow’s Storage

Smaller disks that hold more

a single-electron memory chip the size of a thumbnail that can store all the sounds and images of a full-length feature film

Tomorrow’s Output

Flat-panel screens are replacing desktop CRTs at an ever-increasing rate

Retinal display that works without a screen

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 inventing the future tomorrow s peripherals84

Computer Confluence 7/eChapter 3Inventing the Future: Tomorrow’s Peripherals

Tomorrow’s Input: Sensors

More sophisticated devices will serve as eyes, ears, and other types of sense organs for computer networks

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 lesson summary

A computer terminal is not some clunky old television with a typewriter in front of it. It is an interface where the mind and body can connect with the universe and move bits of it about.

—Douglas Adams, author of The Hitchhiker’s Guide to the Galaxy

Computer Confluence 7/eChapter 3Lesson Summary

Peripherals allow computer to communicate with the outside world and store information for later useinformation

The most common input devices today are the keyboard and the mouse

A variety of other input devices can be connected to the computer

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 lesson summary86

Computer Confluence 7/eChapter 3Lesson Summary

Output devices perform the opposite function: They accept strings of bits from the computer and transform them into a form that is useful or meaningful outside the computer

Storage devices are capable of two-way communication with the computer: Because of their high-speed random access capability are the most common forms of storage on modern computers

© 2006 Prentice-Hall, Inc.

computer confluence 7 e chapter 3 lesson summary87

As a rule, men worrymore about what they can’t see than about what they can.

—Julius Caesar

Computer Confluence 7/eChapter 3Lesson Summary

Network connections make it possible for computers to communicate with one another directly

© 2006 Prentice-Hall, Inc.