QuestionQuestion

What are the three essential What are the three essential components of a modern components of a modern computer?computer?– Be general or specificBe general or specific

AnnouncementAnnouncement

Definition of a ComputerDefinition of a Computer

A computer is an device that A computer is an device that receives information (input), receives information (input), processes information, and outputs processes information, and outputs informationinformation

input/output device that processes input/output device that processes informationinformation

Computer HardwareComputer Hardware

Key parts of a computerKey parts of a computer Input vs. output Input vs. output Interconnection between partsInterconnection between parts

Essential PartsEssential Parts

Box - Central Processing Unit (CPU)Box - Central Processing Unit (CPU) Monitor - main output deviceMonitor - main output device Keyboard - main input deviceKeyboard - main input device

The Box (CPU)The Box (CPU)

All processing goes through the All processing goes through the boxbox

A simple input/output (I/O) deviceA simple input/output (I/O) device PortsPorts on back for connection of on back for connection of

input and output devicesinput and output devices Disk Disk drivesdrives on front for storage I/O on front for storage I/O

Input vs. Output?Input vs. Output?Classify the following as input or outputClassify the following as input or output

MonitorMonitor KeyboardKeyboard CPU (The Box)CPU (The Box) Floppy DriveFloppy Drive CD-ROMCD-ROM PrinterPrinter ScannerScanner ModemModem

Digital CameraDigital Camera CD Writer/BurnerCD Writer/Burner Hard DriveHard Drive LCD ProjectorLCD Projector Laser PointerLaser Pointer Network CardNetwork Card Bluetooth CardBluetooth Card SpeakersSpeakers

Computer

Monitor

Keyboard

HDFD

CD-RW

Printer

ScannerCameraMouse

Modem

LCD

Output

Input

I/ORead - Write

Legend

Inside the BoxInside the Box

Processor – e.g. Pentium IVProcessor – e.g. Pentium IV Memory – e.g. 256 MB RAMMemory – e.g. 256 MB RAM Storage – e.g. Hard Drive, CD-RWStorage – e.g. Hard Drive, CD-RW Slots & CardsSlots & Cards We will cover this on MondayWe will cover this on Monday

Input: KeyboardsInput: Keyboards

Standard keyboard - 101 key, Standard keyboard - 101 key, letters, number-pad, function keysletters, number-pad, function keys

Microsoft Natural Keyboard - Microsoft Natural Keyboard - “Ergonomic” design, supposedly “Ergonomic” design, supposedly better for wristsbetter for wrists

Wrist support is importantWrist support is important The future?The future?

Output: Types of MonitorsOutput: Types of Monitors

Cathode Ray Tube (CRT) Cathode Ray Tube (CRT) - standard monitor, - standard monitor, inexpensive, good inexpensive, good resolution, good pixel resolution, good pixel sizesize

Flat Panel (Liquid Flat Panel (Liquid Crystal Display - LCD) – Crystal Display - LCD) – more expensive, prices more expensive, prices droppingdropping

Buying a MonitorBuying a Monitor

Size is most important factorSize is most important factor– Get a 17” CRT or 15” LCD or biggerGet a 17” CRT or 15” LCD or bigger

Note 15” LCD is about the same as a 17” CRTNote 15” LCD is about the same as a 17” CRT

– 15” CRT cheaper but will seem very small15” CRT cheaper but will seem very small Dot size advertised, not that big of a Dot size advertised, not that big of a

factorfactor Viewable Area – 15.8” for a 17” CRTViewable Area – 15.8” for a 17” CRT Maximum resolution – look for at least Maximum resolution – look for at least

1280 x 10241280 x 1024

Computer

Monitor

Keyboard

HDFD

CD-RW

Printer

ScannerCameraMouse

Modem

LCD

Output

Input

I/ORead - Write

Legend

Input: MiceInput: Mice

Standard Two-Button: Left Standard Two-Button: Left button for selecting, right button for selecting, right button for propertiesbutton for properties

Wheeled Mouse - Wheel for Wheeled Mouse - Wheel for scrollingscrolling

Trackball - Inverted mouseTrackball - Inverted mouse Touchpad - Touch/tap Touchpad - Touch/tap

sensitivesensitive ““Eraser”/Joystick Eraser”/Joystick

Mice: MechanicsMice: Mechanics

Most mice have a round Most mice have a round ball and rollers – rollers ball and rollers – rollers must be cleanedmust be cleaned

Newer mice are OPTICAL, Newer mice are OPTICAL, using LED and sensor to using LED and sensor to track movementtrack movement

Input: ScannersInput: Scanners Flatbed Scanners - Lay image flat on Flatbed Scanners - Lay image flat on

“copier”-like glass panel. Scanning “copier”-like glass panel. Scanning element moveselement moves

Photo Scanners - Run a single photo Photo Scanners - Run a single photo through a scanner - photo moves, scanning through a scanner - photo moves, scanning element stays stationaryelement stays stationary

What you pay for: resolution, color quality, What you pay for: resolution, color quality, connectivityconnectivity

Speed: USB connection faster than Parallel Speed: USB connection faster than Parallel All scanners on market sufficient for webAll scanners on market sufficient for web

Input: Digital CamerasInput: Digital Cameras

Camera without filmCamera without film Pixel resolution measures number of dotsPixel resolution measures number of dots Pixel resolution is key: 640x480 vs. Pixel resolution is key: 640x480 vs.

1280x1024 (1.3 Megapixels) vs. 2048X1536 1280x1024 (1.3 Megapixels) vs. 2048X1536 (3.3 Megapixels)(3.3 Megapixels)

Storage can be on flash memory cards, Storage can be on flash memory cards, memory sticks, floppy disks, internal, or no memory sticks, floppy disks, internal, or no storage (web cam)storage (web cam)

How to unload images is importantHow to unload images is important

QuestionQuestion

What is the common language in What is the common language in which input and output devices which input and output devices communicate?communicate?

AnswerAnswer

Ones and Zeros.Ones and Zeros. 100011010101010100001010001100011010101010100001010001

011111001010010101010101001011111001010010101010101001010011000001010010101110011010011000001010010101110011011111100010100110 actually 011111100010100110 actually means something to a computermeans something to a computer

Output: PrintersOutput: Printers

Inkjet Printers - Tiny dots of ink on Inkjet Printers - Tiny dots of ink on paperpaper– Can print high quality photosCan print high quality photos– Ink is expensive!Ink is expensive!

Laser Printers - Laser, plastic toner, Laser Printers - Laser, plastic toner, and heat; drawback: no colorand heat; drawback: no color

Color Laser Printers - ~$600 and upColor Laser Printers - ~$600 and up Dot Matrix PrintersDot Matrix Printers

Output - LCD ProjectorsOutput - LCD Projectors

Similar to monitors but project imageSimilar to monitors but project image New to computer market (last 5 New to computer market (last 5

years)years) Expensive, becoming cheaper every Expensive, becoming cheaper every

day (some under $1000 now)day (some under $1000 now) For business and education, some For business and education, some

people getting them for home theatre people getting them for home theatre systemssystems

Two-way Communication: Two-way Communication: ModemModem

MOdulator / DEModualter = MO-DEMMOdulator / DEModualter = MO-DEM Converts digital computer signal to Converts digital computer signal to

analog telephone signal and vice analog telephone signal and vice versaversa

Sends and receives informationSends and receives information 56K is current standard56K is current standard Connect speeds often slower than 56KConnect speeds often slower than 56K

Cable ModemsCable Modems

Cable Modems convert from cable Cable Modems convert from cable interface to Ethernet or USB interface. interface to Ethernet or USB interface.

External, $50-$200 to buyExternal, $50-$200 to buy Must subscribe to Broadband/ Cable Must subscribe to Broadband/ Cable

Internet Service through your cable Internet Service through your cable providerprovider

Best way to go from home but Best way to go from home but expensive ($45/month)expensive ($45/month)

Cable provider has a monopoly so Cable provider has a monopoly so prices won’t dropprices won’t drop

DSLDSL

Digital Subscriber LineDigital Subscriber Line– Works over phone line but doesn’t Works over phone line but doesn’t

interfere with phone callsinterfere with phone calls– The speed is much higher than a The speed is much higher than a

regular modem (1.5 Mbps vs. 56 Kbps) regular modem (1.5 Mbps vs. 56 Kbps) – Works better closer to phone companyWorks better closer to phone company– Not available everywhereNot available everywhere

Network CardsNetwork Cards

Network cards allow connection to Network cards allow connection to the Internet via ETHERNETthe Internet via ETHERNET

Wireless network cards require a Wireless network cards require a wireless router to connectwireless router to connect

Ethernet is FAST!Ethernet is FAST!

Storage MediaStorage Media

Media refers to the objects on Media refers to the objects on which information is storedwhich information is stored

Singular of word is mediumSingular of word is medium A CD is a medium for storage, a A CD is a medium for storage, a

floppy disk is a medium, …floppy disk is a medium, …

Storage: Magnetic MediaStorage: Magnetic Media

““Drive” Storage: Drive” Storage: magneticmagnetic film film stores 1s and 0sstores 1s and 0s

Hard Drives - Internal, sealed plattersHard Drives - Internal, sealed platters Floppy Drive - One flexible platterFloppy Drive - One flexible platter Zip Drive – Very high capacity floppyZip Drive – Very high capacity floppy Most rewritable storage is magneticMost rewritable storage is magnetic

Storage: Optical Media Read Storage: Optical Media Read OnlyOnly

CD-ROM – 650MB or 700 MB, CD-ROM – 650MB or 700 MB, read read onlyonly, etched pits, etched pits

drives 32X etc. for speed relative to normaldrives 32X etc. for speed relative to normal

DVD - stands for Digital Versatile Disc, DVD - stands for Digital Versatile Disc, 4.7 Gb (7X CD)4.7 Gb (7X CD)

CD Burners – Optical CD Burners – Optical Read/WriteRead/Write

CD RWCD RW– 48x/16x/52x means 48x maximum 48x/16x/52x means 48x maximum

write speed, 16x max. rewrite speed, write speed, 16x max. rewrite speed, and 52x max. read speedand 52x max. read speed

Media: CD-R is cheapest, write Media: CD-R is cheapest, write onceonce

CD-RW – good medium for CD-RW – good medium for transporting filestransporting files