1. Teachers Discovering Computers Integrating Technology in a Changing World 8th Edition Chapter Four Hardware for Educators

2. Chapter Objectives Describe the system unit Define the term bit and describe how a series of bits are used to represent data Identify the major components of the system unit and explain their functions Explain how the CPU uses the four steps of a machine cycle to process data Describe the four types of input as well as input devices and pointing devices List the characteristics of a keyboard and identify various types of keyboards 2

3. Chapter Objectives Differentiate among the four types of output Identify different types of output devices Explain differences among various types of printers Differentiate between storage and memory Identify types of storage media and devices Differentiate between CDs, DVDs, and BDs 3

4. The System Unit System unit – Boxlike case that houses the electronic components a computer uses to process data 4

5. Data Representation Analog vs. Digital Digital – Two states (1) on (0) off 5

6. Data Representation Binary number system Combination of ones and zeroes represent characters 6

7. Data Representation ASCII – American Standard Code for Information Interchange – Converting a keyboard stroke into a byte 7

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9. The Components of the System Unit The Motherboard – Contains many of the electronic components – Chip A small piece of semiconducting material usually no bigger than one-half-inch square and is made up of many layers of circuits and microscopic components that carry electronic signals 9

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11. The Components of the System Unit CPU – Interprets and carries out the basic instructions that operate a computer – Microprocessor manages most of a computer’s operations 11

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13. The Components of the System Unit The Control Unit – A component of the CPU that directs and coordinates most of the operations in the computer Fetch - get the next instruction from memory Decode - translate the instruction Execute - carry out the command Store the result - write the result to memory Machine cycle 13

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15. The Components of the System Unit The Arithmetic/Logic Unit – Performs the execution part of the machine cycle – Arithmetic (addition, subtraction, multiplication, division) – Comparison (greater than, equal to, less than) – Logical (AND, OR, NOT) 15

16. The Components of the System Unit The System Clock – Synchronizes all computer operations – Each tick is called a clock cycle – Faster clock means more instructions the CPU can execute each second – Speed measured in gigahertz (GHz) 16

17. The Components of the System Unit Memory – Used to store data and instructions The operating system and other system software Application software Data being processed by application programs – Bytes are stored at specific locations or addresses 17

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19. The Components of the System Unit Memory – Size of memory is measured by the number of bytes available – Volatile memory – contents are lost when the computer is turned off – Nonvolatile memory – contents are not lost when the computer is turned off 19

20. The Components of the System Unit Random Access Memory (RAM) – The memory chips in the system unit – When the computer starts, certain operating system files are loaded from a storage device into RAM – Synchronous Dynamic RAM (SDRAM) – Dual Inline Memory Module (DIMM) 20

21. The Components of the System Unit Random Access Memory (RAM) – RAM Chips Smaller in size than processor chips Commonly hold up to 4 gigabytes of memory 21

22. The Components of the System Unit Random Access Memory (RAM) – Configuring RAM The more RAM, the more programs and files a computer can work on at once Software usually tells you how much RAM is required For an application to perform optimally, you usually need more than the minimum specifications 22

23. The Components of the System Unit Read-Only Memory (ROM) – Cannot be modified – Contents not lost when the computer is turned off Flash Memory – Type of nonvolatile memory that can be erased electronically and rewritten on 23

24. The Components of the System Unit Expansion Slots and Expansion Cards – Expansion slot A socket on the motherboard that can hold an expansion card Add new devices or capabilities to the computer – Expansion card Circuit board that enhances functions of a system component and/or provides connections to peripherals – Plug and Play 24

25. The Components of the System Unit Removable Memory Devices – Flash memory cards – USB flash drives – PC Cards – ExpressCard modules 25

26. The Components of the System Unit Ports and Connectors – Port Point of attachment to the system unit Usually on the back and front of the system unit – Connectors Used to plug into ports – Male connectors – Female connectors 26

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28. The Components of the System Unit Ports and Connectors – USB – USB 2.0 – USB 3.0 – FireWire – Bluetooth 28

29. What is Input? Any data or instructions you enter into the memory of a computer – Data – unprocessed items – Programs - series of instructions that tells the computer how to perform a task – Commands - an instruction given to a computer program – User responses - responses to questions or messages from the software 29

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31. What are Input Devices? Any hardware component that allows you to enter data, programs, commands, and user responses into a computer 31

32. What are Input Devices? The Keyboard – Typing area – Numeric keypad – Toggle keys – Status lights – Arrow keys - arrow control keys – Function keys – Specialized buttons 32

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34. What are Input Devices? Pointing Devices – An input device that allows you to control a pointer on the screen Block arrow I-beam Pointing hand 34

35. What are Input Devices? Pointing Devices – Mouse One or two button mouse Scroll wheel Moving the mouse pointer Clicking Dragging Double-clicking Optical mouse Wireless mouse 35

36. What are Input Devices? Touchpad and Pointing Stick – Touchpad – small, flat, rectangular pointing device that is sensitive to pressure and motion – Pointing Stick – pressure- sensitive pointing device shaped like a pencil eraser 36

37. What are Input Devices? Pointing Devices – Trackball Like a mouse, but the ball mechanism is on top Requires frequent cleaning Good when you have limited desk space 37

38. What are Input Devices? Pointing Devices – Joystick Uses the movement of a vertical lever Often used with games – Wheel Steering-wheel type input device Used to simulate driving a car or other vehicle 38

39. What are Input Devices? Pointing Devices – Touch and multi-touch screens Monitor has a touch sensitive panel Used to issue simple commands or choose from a list of options Some models of desktop and notebook computers, all tablet computers, and many mobile devices have touch screens Kiosks 39

40. What are Input Devices? Optical Scanners – Captures an entire page of text or images such as photographs or artwork electronically – Converts the text or image on the original document into digital data that can be stored on a storage medium and processed by the computer 40

41. What are Input Devices? Pen Input – Users write, draw, and tap on a flat surface to enter input – Stylus – small metal or plastic device that looks like a tiny ink pen but uses pressure instead of ink – Digital pen – slightly larger than a stylus and provides more functionality 41

42. What are Input Devices? Digital Cameras – Allows you to take pictures and store the photographed images digitally – Download, or transfer, pictures to your computer 42

43. What are Input Devices? Audio and Video Input – Audio input Entering speech, music, or sound effects Sound card Speech Recognition – Computer’s capability of distinguishing spoken words 43

44. What are Input Devices? Audio and Video Input – Video input Capturing a full-motion recording onto a computer and storing the video on a computer’s storage medium 44

45. What are Input Devices? 45

46. What is Output? Text Graphics Audio Video 46

47. What are Output Devices? Any computer component capable of conveying information to the user Commonly used output devices – Display devices – Printers – Data projectors – Facsimile machines – Multifunction devices – Interactive whiteboards – Speakers, headphones, and earphones 47

48. What are Output Devices? Display Devices – Screen housed in a plastic or metal case – Variety of sizes – Cathode ray tube (CRT) – Pixels – Flat-panel displays LCD (liquid crystal display) monitors LCD screens Plasma monitors 48

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50. What are Output Devices? Plasma Monitors – Some can measure more than 150 inches wide – Uses gas plasma technology, which sandwiches a layer of gas between two glass plates 50

51. What are Output Devices? Monitor Quality – Resolution (sharpness and clarity) Expressed as number of columns and rows – 1600 x 1200 51

52. What are Output Devices? Televisions – iPad users can stream their music, photos, and videos wirelessly to a display device using AppleTV and AirPlay – With game consoles, such as Microsoft’s Xbox 360, Nintendo’s Wii, and Sony’s PlayStation 3, the output device often is a television 52

53. What are Output Devices? Printers – An output device that produces text and graphics on a physical medium such as paper or transparency film – Hard copy (printout) – Portrait orientation vs. landscape orientation – Printing requirements vary 53

54. What are Output Devices? 54

55. What are Output Devices? Nonimpact Printers – Do not strike paper – Much quieter – Ink-jet printers Spray tiny drops of ink onto the paper Both black-and-white and color – Photo printers Produce photo lab quality pictures Many use ink-jet technology 55

56. What are Output Devices? Nonimpact Printers – Laser printers High-speed, high-quality nonimpact printer Very high quality resolution 56

57. What are Output Devices? Data Projectors – Allows an audience to view output – LCD projectors – Digital light processing (DLP) projector 57

58. What are Output Devices? Facsimile (Fax) Machine – Used to transmit and receive an image of a document over a telephone line – Stand-alone – Fax modem 58

59. What are Output Devices? Multifunction Devices – Can print, scan, copy and fax – Less space – Lower cost than separate units 59

60. What are Output Devices? Interactive whiteboards – Touch-sensitive device, resembling a dry-erase board – A presenter controls the computer program used to display the image by: Clicking a remote control Touching the whiteboard Drawing on or erasing the whiteboard Writing on a special tablet 60

61. What are Output Devices? Speakers, Headphones, and Earphones – Voice output – Audio output device – Internal speaker 61

62. What is Storage? The media on which data, instructions, and information are kept The devices that record and retrieve data, instructions, and information Similar to a filing cabinet 62

63. Storage Media and Devices Storage medium – Also called secondary storage – Physical material Storage device – Mechanism used to record and retrieve these items to and from a storage medium – Capacity measured in megabytes or gigabytes 63

64. Storage Media and Devices Magnetic Disk – Uses magnetic patterns to store data, instructions, and information on the disk’s surface – Formatting is the process of preparing a disk for reading and writing by organizing the disk into storage locations called tracks and sectors 64

65. Storage Media and Devices Hard Disks – Provide large storage capacity – Sizes range from 320 GB to 1.5 TB – Consists of several inflexible, circular disks, called platters – Magnetic storage device – Formatting 65

66. Storage Media and Devices Miniature and Portable Hard Disks – Miniature hard disks are found in consumer electronics and have greater storage capacities than flash memory – External hard disks connect to a USB or FireWire port by a cable 66

67. Storage Media and Devices Solid State Drives – A storage device that typically uses flash memory to store data, instructions, and information and contains no moving parts – Range in size – Used in all types of computers 67

68. Storage Media and Devices Optical discs – Type of storage medium that consists of a flat, round, portable disc made of metal, plastic, and lacquer that is written to and read from using a laser 68

69. Storage Media and Devices CDs and DVDs – Optical storage media – Used to distribute software – Laser reads pits on the surface – Used on multimedia computers – Several types 69

70. Storage Media and Devices Care of Optical Discs – Can last up to 100 years if properly cared for – Never bend a disc – Avoid extreme temperatures and humidity – Keep away from contaminants – Do not stack or touch discs – Use a protective case (jewel box or disc storage case) 70

71. Storage Media and Devices CD-ROM – Compact disc read-only memory – Can contain text, graphics, video, as well as sound – Can hold up to 1 GB – Used to distribute software 71

72. Storage Media and Devices CD-R and CD-RW – Compact disc-recordable Can write on each part of the disc only one time Cannot be erased – Compact disc-rewriteable Can write on multiple times Erasable disc 72

73. Storage Media and Devices DVD and BD – Digital video disc read-only memory (DVD-ROM) Can store from 4.7 GB to 17 GB High quality DVD-ROM drives – BD (Blu-ray Disc) has storage capacities of 100GB, with expectations of exceeding 200 GB 73

74. Storage Media and Devices Miniature Mobile Storage Media 74

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76. Storage Media and Devices USB Flash Drive – Storage device that plugs into a USB port on a computer or mobile device Smart Card – Similar in size to a credit card – Stores data on a thin microprocessor embedded in the card Cloud Storage – Rapidly growing Internet service that provides storage to computer users – Apple’s iCloud 76

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