McGraw-Hill/Irwin © 2008 The McGraw-Hill Companies,All Rights Reserved

Appendix AAppendix A

Computer Hardware and SoftwareComputer Hardware and Software

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STUDENT LEARNING OUTCOMESSTUDENT LEARNING OUTCOMES

1.1. Define IT and its two basic categories: Define IT and its two basic categories: hardware and software.hardware and software.

2.2. Describe the categories of computers based on Describe the categories of computers based on size.size.

3.3. Compare the roles of personal productivity, Compare the roles of personal productivity, vertical market, and horizontal market vertical market, and horizontal market software.software.

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STUDENT LEARNING OUTCOMESSTUDENT LEARNING OUTCOMES

4.4. Describe the roles of operating system Describe the roles of operating system software and utility software as components software and utility software as components of system software.of system software.

5.5. Define the purpose of each of the six major Define the purpose of each of the six major categories of hardware.categories of hardware.

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INTRODUCTIONINTRODUCTION

• Information technologyInformation technology – any computer-based – any computer-based tool that people use to work with information tool that people use to work with information and support the information and information-and support the information and information-processing needs of an organizationprocessing needs of an organization

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• Information technologyInformation technology – any computer-based – any computer-based tool that people use to work with information tool that people use to work with information and support the information and information-and support the information and information-processing needs of an organizationprocessing needs of an organization

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Many Tools of ITMany Tools of IT

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TECHNOLOGY QUICK TOURTECHNOLOGY QUICK TOUR

• HardwareHardware – physical devices that make up a – physical devices that make up a computer (or computer system)computer (or computer system)

• SoftwareSoftware – set of instructions that hardware – set of instructions that hardware executes to carry out a specific task for youexecutes to carry out a specific task for you

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Six Categories of HardwareSix Categories of Hardware

1.1. Input deviceInput device – use to enter information and – use to enter information and commandscommands

2.2. Output deviceOutput device – hear, see, or otherwise – hear, see, or otherwise recognize the results of information-recognize the results of information-processing requestsprocessing requests

3.3. Storage deviceStorage device – store information for use at a – store information for use at a later timelater time

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Six Categories of HardwareSix Categories of Hardware

4.4. ProcessingProcessing– CPUCPU – hardware that interprets and executes – hardware that interprets and executes

software and coordinates all hardwaresoftware and coordinates all hardware– RAMRAM – temporary holding area for information – temporary holding area for information

and softwareand software

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Six Categories of HardwareSix Categories of Hardware5.5. Telecommunications deviceTelecommunications device – send – send

information to and receive it from another information to and receive it from another person or computer in a networkperson or computer in a network

6.6. Connecting deviceConnecting device – lets you connect – lets you connect peripherals to your computer, such asperipherals to your computer, such as

– CablesCables– PortsPorts– Expansion boardsExpansion boards– Etc.Etc.

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Six Categories of HardwareSix Categories of Hardware

Keyboard (input)CDs (storage)

Video card (connecting)

CPU

Cable modem (telecommunications)

Monitor (output)

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Two Major Categories of SoftwareTwo Major Categories of Software1.1. Application softwareApplication software – enables you to solve – enables you to solve

specific problems or perform specific tasksspecific problems or perform specific tasks

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Two Major Categories of SoftwareTwo Major Categories of Software

2.2. System softwareSystem software – handles tasks specific to – handles tasks specific to technology management and coordinates the technology management and coordinates the interaction of all technology devicesinteraction of all technology devices

• Two main types of system softwareTwo main types of system software– Operating system softwareOperating system software– Utility softwareUtility software

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Types of System SoftwareTypes of System Software

• Operating system softwareOperating system software – controls – controls application software and manages hardware application software and manages hardware devicesdevices

• Utility softwareUtility software – provides additional – provides additional functionality to your operating systemfunctionality to your operating system– Anti-virusAnti-virus– Screen saverScreen saver– Etc.Etc.

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COMPUTER CATEGORIES COMPUTER CATEGORIES (BY SIZE)(BY SIZE)

• Personal digital assistant (PDA) Personal digital assistant (PDA) – small – small handheld computer for personal tasks like handheld computer for personal tasks like appointment scheduling and address book appointment scheduling and address book maintenancemaintenance

• Tablet PC Tablet PC – pen-based computer with the – pen-based computer with the functionality of a notebook or desktop functionality of a notebook or desktop

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COMPUTER CATEGORIES (BY SIZE)COMPUTER CATEGORIES (BY SIZE)

• Notebook computer Notebook computer – small, portable, fully – small, portable, fully functional, battery-powered computerfunctional, battery-powered computer

• Desktop computer Desktop computer – most popular type of – most popular type of personal computer personal computer

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COMPUTER CATEGORIES (BY SIZE)COMPUTER CATEGORIES (BY SIZE)

PDA Notebook

Desktop

Tablet PC

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COMPUTER CATEGORIES (BY SIZE)COMPUTER CATEGORIES (BY SIZE)

• Minicomputer (mid-range computer)Minicomputer (mid-range computer) – meets – meets needs of several people simultaneously in a needs of several people simultaneously in a small or medium-sized businesssmall or medium-sized business

• Mainframe computerMainframe computer – meets needs of – meets needs of hundreds of people in a large businesshundreds of people in a large business

• SupercomputerSupercomputer – fastest, most powerful, and – fastest, most powerful, and most expensive type of computer most expensive type of computer

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COMPUTER CATEGORIES (BY SIZE)COMPUTER CATEGORIES (BY SIZE)

Minicomputers

MainframeSupercomputer

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SOFTWARE – INTELLECTUAL SOFTWARE – INTELLECTUAL INTERFACEINTERFACE

• Personal productivity softwarePersonal productivity software – helps you – helps you perform personal tasksperform personal tasks– Writing memos (word processing)Writing memos (word processing)– Creating graphs (spreadsheet)Creating graphs (spreadsheet)– Creating slide presentations (presentation)Creating slide presentations (presentation)

• Software suiteSoftware suite – several applications bundled – several applications bundled together (usually productivity software) together (usually productivity software)

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Personal Productivity SoftwarePersonal Productivity Software

• Word processingWord processing – helps you create letters, – helps you create letters, memos, and other basic documentsmemos, and other basic documents

• SpreadsheetSpreadsheet – helps you work with numbers, – helps you work with numbers, perform calculations and create graphs perform calculations and create graphs

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Personal Productivity SoftwarePersonal Productivity Software

• PresentationPresentation – helps you create and edit – helps you create and edit information that will appear in slidesinformation that will appear in slides

• Desktop publishingDesktop publishing – – extends word processing extends word processing by including design and formatting techniques by including design and formatting techniques to enhance the appearance of the document to enhance the appearance of the document

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Personal Productivity SoftwarePersonal Productivity Software

• Personal information management (PIM)Personal information management (PIM) – – helps you create and maintain to-do lists, helps you create and maintain to-do lists, appointments, calendars, etc. appointments, calendars, etc.

• Personal financePersonal finance – helps you maintain your – helps you maintain your checkbook and handle other personal finance checkbook and handle other personal finance tasks tasks

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Personal Productivity SoftwarePersonal Productivity Software

• Web authoringWeb authoring – helps you design and – helps you design and develop Web sitesdevelop Web sites

• GraphicsGraphics – helps you create and edit photos – helps you create and edit photos and artand art

• CommunicationsCommunications – helps you communicate – helps you communicate with others with others

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Personal Productivity SoftwarePersonal Productivity Software

• Database management system (DBMS)Database management system (DBMS) – – helps you specify the logical organization for a helps you specify the logical organization for a database; access and use the information database; access and use the information within a database within a database

• The focus of Chapter 3The focus of Chapter 3

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Vertical & Horizontal Market SoftwareVertical & Horizontal Market Software

• Vertical market software – Vertical market software – application application software for a specific industrysoftware for a specific industry– Patient-scheduling softwarePatient-scheduling software– Restaurant management softwareRestaurant management software

• Horizontal market softwareHorizontal market software – application – application software suitable for use in many industriessoftware suitable for use in many industries– Payroll, inventory, and billing Payroll, inventory, and billing

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System SoftwareSystem Software

• Operating system software Operating system software – Microsoft Windows XP HomeMicrosoft Windows XP Home – update of Office– update of Office– Microsoft Windows XP ProMicrosoft Windows XP Pro – update of Office Pro – update of Office Pro– Microsoft Windows Vista – Microsoft Windows Vista – Microsoft’s newest Microsoft’s newest

personal operating systempersonal operating system– Mac OS Mac OS – – Operating system for MacsOperating system for Macs– Linux Linux – powerful open-source operating system – powerful open-source operating system

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MultitaskingMultitasking• MultitaskingMultitasking – working with more than one – working with more than one

application at a timeapplication at a time

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Utility SoftwareUtility Software• Utility Software – Utility Software – adds functionality to adds functionality to

operating system softwareoperating system software– Anti-virus softwareAnti-virus software – detects and removes or – detects and removes or

quarantines computer virusesquarantines computer viruses– Crash-proof softwareCrash-proof software – helps save information if – helps save information if

your system crashesyour system crashes– Uninstaller softwareUninstaller software – removes software from – removes software from

your hard disk your hard disk – Disk optimization software Disk optimization software – organizes – organizes

information on your hard diskinformation on your hard disk– Spam blocker Spam blocker – filters unwanted e-mail– filters unwanted e-mail

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HARDWARE – PHYSICAL HARDWARE – PHYSICAL INTERFACEINTERFACE

• Representation of informationRepresentation of information– Binary digit (bit)Binary digit (bit) – smallest unit of information – smallest unit of information

your computer can processyour computer can process– ByteByte – eight bits or the number of bits it takes to – eight bits or the number of bits it takes to

represent one natural characterrepresent one natural character – ASCII (American Standard Code for Information ASCII (American Standard Code for Information

Interchange)Interchange) – coding system that personal – coding system that personal computers use computers use

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Information RepresentationInformation Representation

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Common Input DevicesCommon Input Devices

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Common Input DevicesCommon Input Devices

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Input Devices – Information & Input Devices – Information & CommandsCommands

• KeyboardsKeyboards – most frequently input devices for – most frequently input devices for notebooks and desktops to enter information notebooks and desktops to enter information and commandsand commands

• StylusStylus – most frequently used input devices for – most frequently used input devices for PDAs and tablet PCs to enter information and PDAs and tablet PCs to enter information and commands commands

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Input Devices – CommandsInput Devices – Commands

• Pointing Device – Pointing Device – used to input commandsused to input commands– MouseMouse – device you use to click on icons and – device you use to click on icons and

buttonsbuttons– TrackballTrackball – similar to a mechanical mouse, but – similar to a mechanical mouse, but

with the ball on top with the ball on top

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Input Devices – CommandsInput Devices – Commands

• Touchpad Touchpad – dark rectangle you use to move – dark rectangle you use to move the cursor with your fingerthe cursor with your finger

• Pointing stick Pointing stick – a little rod, used mostly on – a little rod, used mostly on notebooks notebooks

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Input Devices – Game ControllersInput Devices – Game Controllers

• Game controller – Game controller – used for gaming to control used for gaming to control screen actionscreen action– Gaming wheelGaming wheel – steering wheel and foot pedals for – steering wheel and foot pedals for

virtual driving virtual driving

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Input Devices – Game ControllersInput Devices – Game Controllers

– Joystick Joystick – controls action with a vertical handle – controls action with a vertical handle and programmable buttonsand programmable buttons

– Gamepad Gamepad – device with programmable buttons, – device with programmable buttons, thumb sticks, and a directional pad thumb sticks, and a directional pad

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ScannersScanners

• ScannersScanners – used to convert information that – used to convert information that exists in visible form into electronic formexists in visible form into electronic form– Image scanner Image scanner – captures images, photos, text, – captures images, photos, text,

and artwork and artwork – Bar code scanner Bar code scanner – reads information in the form – reads information in the form

of vertical bars of vertical bars

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ScannersScanners

– Optical mark reader Optical mark reader – detects the presence or – detects the presence or absence of a markabsence of a mark

– Optical character reader Optical character reader – reads characters that – reads characters that appear on paper or sales tag (used in POS appear on paper or sales tag (used in POS systems)systems)

– Biometric scanner Biometric scanner – scans a human physical – scans a human physical attribute, like a fingerprint or iris, for security attribute, like a fingerprint or iris, for security purposes purposes

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Digital CamerasDigital Cameras

• Digital cameraDigital camera – captures still image or video – captures still image or video as a series of 1s and 0sas a series of 1s and 0s– Digital still cameraDigital still camera – digitally captures still – digitally captures still

images in varying resolutionsimages in varying resolutions– Digital video cameraDigital video camera – captures video digitally – captures video digitally– WebcamWebcam – captures digital video for the Web – captures digital video for the Web

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Common Output DevicesCommon Output Devices

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Common Output Devices - MonitorsCommon Output Devices - Monitors

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MonitorsMonitors

• CRTCRT – monitors that look like traditional TV – monitors that look like traditional TV setssets

• Flat-panel display Flat-panel display – thin, lightweight monitors – thin, lightweight monitors that take up much less space than CRTs that take up much less space than CRTs

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MonitorsMonitors

• Two types of flat-panel displaysTwo types of flat-panel displays1.1. Liquid crystal display (LCD) monitorLiquid crystal display (LCD) monitor – sends – sends

electricity through crystallized liquid between electricity through crystallized liquid between layers of glass or plastic layers of glass or plastic

2.2. Gas plasma displayGas plasma display – sends electricity through gas – sends electricity through gas trapped between layers of glass or plastic trapped between layers of glass or plastic

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Monitor ConsiderationsMonitor Considerations

• Viewable image size (VIS)Viewable image size (VIS) – the size of the – the size of the image on a monitorimage on a monitor

• Resolution of a screenResolution of a screen – the number of pixels – the number of pixels it hasit has

• Pixels (picture elements)Pixels (picture elements) – the dots that make – the dots that make up the imageup the image

• Dot pitchDot pitch – the distance between the centers of – the distance between the centers of two like-colored pixels two like-colored pixels

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PrintersPrinters

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PrintersPrinters

• Resolution of a printerResolution of a printer – the number of dots per – the number of dots per square inch (dpi) it producessquare inch (dpi) it produces

• TypesTypes– Inkjet printer Inkjet printer – makes images by forcing ink through – makes images by forcing ink through

nozzlesnozzles– Laser printer Laser printer – forms images using the same – forms images using the same

electrostatic process that photocopiers useelectrostatic process that photocopiers use– Multifunction printer Multifunction printer – scan, copy, and fax, as well as – scan, copy, and fax, as well as

printprint– PlotterPlotter – forms output by moving pen across paper – forms output by moving pen across paper

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Common Storage DevicesCommon Storage Devices

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Capacity of Storage DevicesCapacity of Storage Devices

• Megabyte (MB or M or Meg)Megabyte (MB or M or Meg) – about 1 – about 1 million bytesmillion bytes

• Gigabyte (GB or Gig)Gigabyte (GB or Gig) – about 1 billion bytes – about 1 billion bytes

• Terabyte (TB) Terabyte (TB) – about 1 trillion bytes – about 1 trillion bytes

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Magnetic Storage MediaMagnetic Storage Media

• Hard diskHard disk – magnetic storage with one or – magnetic storage with one or more thin metal platters sealed inside the drive more thin metal platters sealed inside the drive

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Optical Storage MediaOptical Storage Media

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Optical Storage MediaOptical Storage Media

• Optical storage mediaOptical storage media – plastic discs on which – plastic discs on which information is stored, deleted, and changed information is stored, deleted, and changed using laser technologyusing laser technology

• Two typesTwo types– CDsCDs– DVDs DVDs

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CDsCDs

• CD-ROM (compact disc read-only memory)CD-ROM (compact disc read-only memory) – – information cannot be changedinformation cannot be changed

• CD-R (compact disc – recordable)CD-R (compact disc – recordable) – write one – write one time onlytime only

• CD-RW (compact disc – rewritable)CD-RW (compact disc – rewritable) – save, – save, change, and delete files repeatedly change, and delete files repeatedly

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DVDsDVDs

• DVD-ROMDVD-ROM – high capacity; information – high capacity; information cannot be changedcannot be changed

• DVD-R or DVD+R (DVD – recordable)DVD-R or DVD+R (DVD – recordable) – – high capacity; write one time onlyhigh capacity; write one time only

• DVD-RW or DVD+RDVD-RW or DVD+R (depending on (depending on manufacturer) – save, change, delete manufacturer) – save, change, delete repeatedly repeatedly

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Flash Memory Devices & CardsFlash Memory Devices & Cards

• Flash memory device Flash memory device – very small storage – very small storage device that plugs into USB portdevice that plugs into USB port

• Flash memory cardFlash memory card – high capacity storage – high capacity storage laminated inside a small piece of plastic laminated inside a small piece of plastic

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Common Types of Flash MemoryCommon Types of Flash Memory

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Flash Memory CardsFlash Memory Cards

• xD-Picture (xD) cardxD-Picture (xD) card – rectangular; smaller – rectangular; smaller than a penny and about as thick with one than a penny and about as thick with one curved sidecurved side

• Secure Digital (SD) card Secure Digital (SD) card and and MultiMediaCard (MMCMultiMediaCard (MMC) – look the same but ) – look the same but SD has copy protection; are both larger and SD has copy protection; are both larger and thicker than a quarter (but rectangular) thicker than a quarter (but rectangular)

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Flash Memory CardsFlash Memory Cards

• CompactFlash (CF) cardCompactFlash (CF) card – almost square; – almost square; larger than a half-dollarlarger than a half-dollar

• SmartMedia (SM) cardSmartMedia (SM) card – rectangular; longer – rectangular; longer than CFthan CF

• Memory Stick Media cardMemory Stick Media card – elongated card as – elongated card as wide as a penny developed by Sony wide as a penny developed by Sony

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CPU and RAMCPU and RAM

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CPU and RAMCPU and RAM

• CPU and RAM work together to form the CPU and RAM work together to form the brain of your computerbrain of your computer

• CPU speed measured in gigahertz (GHz)CPU speed measured in gigahertz (GHz)– GHzGHz – number of billions of CPU cycles per – number of billions of CPU cycles per

secondsecond– CPU (machine) cycle CPU (machine) cycle – retrieve, decode, and – retrieve, decode, and

execute instruction, then return result to RAM if execute instruction, then return result to RAM if necessary necessary

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CPU ComponentsCPU Components

• Control unitControl unit – directs what happens in the – directs what happens in the CPU and the rest of your computerCPU and the rest of your computer

• Arithmetic logic unit (ALU)Arithmetic logic unit (ALU) – performs – performs arithmetic, comparison, and logic operationsarithmetic, comparison, and logic operations

• CPU cacheCPU cache – CPU memory where instructions – CPU memory where instructions wait until they’re neededwait until they’re needed

• CPU clockCPU clock – beats to keep instructions and – beats to keep instructions and information moving in synchronized fashioninformation moving in synchronized fashion

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System BusSystem Bus

• System busSystem bus – electrical pathways that move – electrical pathways that move information between motherboard information between motherboard components, especially between CPU and components, especially between CPU and RAM RAM

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CPU and Ram at WorkCPU and Ram at Work

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CPU (Machine Cycle)CPU (Machine Cycle)

1.1. RetrieveRetrieve: The control unit sends to RAM for : The control unit sends to RAM for the instructions and information it needsthe instructions and information it needs

2.2. DecodeDecode: CPU gets the instruction out of cache : CPU gets the instruction out of cache and examines it to see what to doand examines it to see what to do

3.3. ExecuteExecute: Does what the instruction says to do: Does what the instruction says to do

4.4. StoreStore: Sends the result of processing to be : Sends the result of processing to be stored in RAM if necessary stored in RAM if necessary

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Notebook CPUs and RAMNotebook CPUs and RAM

• Mobile CPUMobile CPU – type of CPU that changes – type of CPU that changes speed, and therefore power consumption, in speed, and therefore power consumption, in response to fluctuation in useresponse to fluctuation in use

• RAM for notebooks comes in smaller modules RAM for notebooks comes in smaller modules than RAM for desktops than RAM for desktops

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Connectors and PortsConnectors and Ports

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Ports and ConnectorsPorts and Connectors

• PortPort – place on your system unit, monitor, or – place on your system unit, monitor, or keyboard through which information and keyboard through which information and instructions flow to and from computer instructions flow to and from computer

• Connector – something like a cable; can also Connector – something like a cable; can also be wirelessbe wireless

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Ports and ConnectorsPorts and Connectors

• Some ports work with plug-and-play and hot-Some ports work with plug-and-play and hot-swap ports and devicesswap ports and devices– Plug and playPlug and play – operating system feature that – operating system feature that

finds and installs the driver for the devicefinds and installs the driver for the device– Hot swapHot swap – operating system feature that allows – operating system feature that allows

you to plug or unplug a device while the computer you to plug or unplug a device while the computer is running is running

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PortsPorts

• USB (universal serial bus) portUSB (universal serial bus) port – fits small, – fits small, flat, plug-and-play, hot-swap USB connectorsflat, plug-and-play, hot-swap USB connectors

• Firewire port (IEEE1394 or I-Link)Firewire port (IEEE1394 or I-Link) – fits – fits hot-swap, plug-and-play Firewire connectors hot-swap, plug-and-play Firewire connectors

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PortsPorts

• PS/2 portPS/2 port – fits PS/2 connectors (used for – fits PS/2 connectors (used for keyboards and mice)keyboards and mice)

• Parallel portParallel port – fits parallel large flat parallel – fits parallel large flat parallel connectors found on printers connectors found on printers

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Common Ports & ConnectorsCommon Ports & Connectors

Serial Ethernet

USBFirewire

Parallel

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Wireless ConnectionsWireless Connections

• Infrared IR or IrDA (infrared data Infrared IR or IrDA (infrared data association)association) – uses red light to send and – uses red light to send and receive informationreceive information

• BluetoothBluetooth – transmits information as radio – transmits information as radio waves for a distance of 30 feetwaves for a distance of 30 feet

• WiFi (wireless fidelity) or IEEE 802.11a, b, WiFi (wireless fidelity) or IEEE 802.11a, b, or gor g – transmits information as radio waves for – transmits information as radio waves for a distance of up to several miles a distance of up to several miles

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Expansion Cards, Slots, & BusExpansion Cards, Slots, & Bus

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Expansion Cards, Slots, & BusExpansion Cards, Slots, & Bus

• Expansion card (board)Expansion card (board) – circuit board that – circuit board that you insert into the expansion slot and connect you insert into the expansion slot and connect to a peripheral deviceto a peripheral device

• Expansion slotExpansion slot – long skinny socket on the – long skinny socket on the motherboard for expansion cardmotherboard for expansion card

• Expansion busExpansion bus – pathways along which – pathways along which information moves between devices (outside information moves between devices (outside the motherboard) and the CPU the motherboard) and the CPU

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Expansion for NotebooksExpansion for Notebooks

• PC CardPC Card – expansion card for a notebook – expansion card for a notebook

• PC Card slotPC Card slot – opening on side or front of a – opening on side or front of a notebook, into which you plug a PC Card notebook, into which you plug a PC Card

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PC Card for a NotebookPC Card for a Notebook

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CAN YOU…CAN YOU…

1.1. Define IT and its two basic categories: Define IT and its two basic categories: hardware and software.hardware and software.

2.2. Describe the categories of computers based on Describe the categories of computers based on size.size.

3.3. Compare the roles of personal productivity, Compare the roles of personal productivity, vertical market, and horizontal market vertical market, and horizontal market software.software.

McGraw-Hill

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CAN YOU…CAN YOU…

4.4. Describe the roles of operating system Describe the roles of operating system software and utility software as components software and utility software as components of system software.of system software.

5.5. Define the purpose of each of the six major Define the purpose of each of the six major categories of hardware.categories of hardware.

OFFICE C-302D OFFICE C-302D

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Team ProjectTeam Project1.1. Each team select one of the following devices:Each team select one of the following devices:

Hard disksHard disksFlash drivesFlash drivesVideo cardsVideo cardsProcessor chipsProcessor chips

2.2. Do a research of different manufacturers of the Do a research of different manufacturers of the selected device types. Note the different types selected device types. Note the different types available, capacities, speeds, prices, power, available, capacities, speeds, prices, power, capabilities, etc.capabilities, etc.

3.3. Make a presentation of your findings comparing the Make a presentation of your findings comparing the different types (of the selected devices) and make a different types (of the selected devices) and make a recommendation on which model of a manufacturer recommendation on which model of a manufacturer of the device gives you:of the device gives you:

• The most for the money spentThe most for the money spent• The best if money is no object.The best if money is no object.