13 computer hardware
- 1. Orasa T. 13 Computer Hardware
- 2. 13 Learning Objectives • Identify the major types and uses of microcomputer, midrange, and mainframe computer systems. • Outline the major technologies and uses of computer peripherals for input, output, and storage.
- 3. 13 Learning Objectives (continued) • Identify the components and functions of a computer system. • Identify the computer system and peripherals you would acquire or recommend for a business of your choice.
- 4. 13 Section I • Computer Systems: End User and Enterprise Computing
- 5. 13 Types of Computer Systems • All computers are systems of input, processing, output, storage, and control components. • Three basic categories – Mainframe – Midrange computers – Microcomputers
- 6. 13 Types of Computer Systems (continued) • Mainframe – Enterprise systems – Superservers – Transaction processors – Supercomputers
- 7. 13 Types of Computer Systems (continued) • Midrange – Network servers – Minicomputers – Web servers – Multi-user systems
- 8. 13 Types of Computer Systems (continued) • Microcomputers – Personal computers – Network computers – Technical workstations – PDAs – Information appliances
- 9. 13 Microcomputer Systems • The most important category of computers – Desktop – Laptop • Workstation computers • Network servers
- 10. 13 Microcomputer Systems (continued) • Selection criteria – Solid performance at a reasonable price – Operating system ready – Connectivity
- 11. 13 Microcomputer Systems (continued) • Network computers – Designed primarily for use with the Internet and corporate intranets – For specialized or limited computing applications – Lower cost of purchase, upgrades, maintenance, and support
- 12. 13 Microcomputer Systems (continued) • Network computers (continued) – Other benefits • Ease of software distribution and licensing • Computing platform standardization • Reduced end user requirements • Improved manageability
- 13. 13 Microcomputer Systems (continued) • Information appliances – PDAs – Set-top boxes and video-game consoles – Wireless PDAs – Cellular and PCS phones
- 14. 13 Microcomputer Systems (continued) • Computer terminals – Dumb terminals – Intelligent terminals – Network terminals – Transaction terminals
- 15. 13 Midrange Computer Systems • Multi-user systems that can manage networks of PCs and terminals • Less costly to buy, operate, and maintain than mainframes • Popular as network servers • Minicomputers
- 16. 13 Mainframe Computer Systems • Large, fast, powerful • Handle high transaction processing volumes or complex computational problems • Super servers for large client/server networks and high-volume Internet websites • Popular for data mining and warehousing
- 17. 13 Mainframe Computer Systems (continued) • Supercomputers – Extremely powerful systems specifically designed for scientific, engineering, and business applications requiring extremely high speeds for massive numeric computations – Use parallel processing architectures – Process at speeds measured in gigaflops and teraflops
- 18. 13 The Computer System Concept • Computers are organized according to the following system functions: – Input • Keyboards • Touch screens • Pens • Electronic mice • Optical scanners • Convert data into electronic form
- 19. 13 The Computer System Concept (continued) – Processing • Central Processing Unit (CPU) – Two subunits » Arithmetic-Logic Unit (ALU) » Control Unit
- 20. 13 The Computer System Concept (continued) – Output • Video display units • Printers • Audio response units • Convert electronic information into human- intelligible form
- 21. 13 The Computer System Concept (continued) – Storage • Store data and software instructions • May also include cache memory • Primary storage unit (hard drive) • Secondary storage – Magnetic disks – Optical disk drives
- 22. 13 The Computer System Concept (continued) – Control • The registers and other circuits of the control unit interpret software instructions and transmit directions to the other components of the computer system
- 23. 13 The Computer System Concept (continued) • Computer processing speeds – Milliseconds (thousandths of a second) – Microseconds (millionths of a second) – Nanoseconds (billionths of a second) – Picoseconds (trillionths of a second)
- 24. 13 The Computer System Concept (continued) – Clock speeds • Megahertz (MHz) – Millions of cycles per second • Gigahertz (GHz) – Billions of cycles per second
- 25. 13 Section II • Computer Peripherals: Input, Output, and Storage Technologies
- 26. 13 Peripherals • Generic name given to all input, output, and secondary storage devices • Depend on direct connections or telecommunications links to the CPU • All peripherals are online devices
- 27. 13 Input Technologies • Natural user interface – Enter data and commands directly into a computer • Electronic mice and touch pads • Optical scanning, handwriting recognition, voice recognition
- 28. 13 Pointing Devices • Used for entering data and text • Work with your operating system’s graphical user interface (GUI) – Electronic mouse – Trackball – Pointing stick – Touch pad – Touch screen
- 29. 13 Pen-Based Computing • Used in many hand-held computers and PDAs – Digitizer pen – Graphics tablet
- 30. 13 Speech Recognition Systems • Digitize, analyze, and classify your speech and its sound patterns • Allow operators to perform data entry without using their hands to key in data or instructions • Speaker-independent • Voice-messaging computers
- 31. 13 Optical Scanning • Read text or graphics and convert them into digital input • Employ photoelectric devices to scan the characters being read
- 32. 13 Optical Scanning (continued) • Optical character recognition (OCR) – Reads OCR characters & codes • Merchandise tags • Product labels • Sort mail, score tests • Hand-held optical scanning wands – Reads bar coding – Universal Product Code (UPC)
- 33. 13 Other Input Technologies • Magnetic stripe technology – Credit cards • Smart cards – Embedded microprocessor chip • Debit, credit, and other cards • Digital cameras – Still cameras – Digital camcorders
- 34. 13 Other Input Technologies (continued) • Magnetic ink character recognition (MICR) technology – Used by banks to sort and post checks and deposit slips – 14 characters of a standardized design – Reader-sorters • Video • Print • Storage
- 35. 13 Video Output • Video monitors – Cathode ray tube (CRT) – Liquid crystal displays (LCDs)
- 36. 13 Printed Output • Inkjet – Spray ink onto the page one line at a time • Laser – Use an electrostatic process similar to a copier
- 37. 13 Storage Trade-Offs
- 38. 13 Storage Trade-Offs (continued) • Computer storage fundamentals – Information is stored through the presence or absence of electronic or magnetic signals • Binary representation – 1 = ON – 0 = OFF
- 39. 13 Storage Trade-Offs (continued) • Computer storage fundamentals (continued) – Bit • The smallest element of data • May have a value of either one or zero – Byte • Basic grouping of bits • Typically, a byte consists of 8 bits and represents one character of data
- 40. 13 Storage Trade-Offs (continued) • Computer storage fundamentals (continued) – Storage capacities • Kilobytes (KB) – 1,000 bytes • Megabytes (MB) – 1 million bytes
- 41. 13 Storage Trade-Offs (continued) • Computer storage fundamentals (continued) • Gigabytes (GB) – 1 billion bytes • Terabytes (TB) – 1 trillion bytes • Petabyte (PB) – 1 quadrillion bytes
- 42. 13 Storage Trade-Offs (continued) • Direct and sequential access – Terms direct access and random access describe the same concept – An element of data or instructions can be directly stored and retrieved by selecting and using any of the locations on the storage media • Each storage position – Has a unique address – Can be individually accessed in approximately the same time
- 43. 13 Storage Trade-Offs (continued) • Direct and sequential access (continued) – Sequential access • Does not have unique storage addresses • Serial process • Data are recorded one after another in a predetermined sequence. • Locating an individual item requires searching all of the data until the desired item is located
- 44. 13 Storage Trade-Offs (continued)
- 45. 13 Semiconductor Memory • Primary storage of your computer • Advantages – Small size – Great speed – Shock and temperature resistant • Disadvantage – Volatility
- 46. 13 Semiconductor Memory (continued) • Two basic types of semiconductor memory – RAM – random access memory • Volatile memory • Read/write memory • “working” memory
- 47. 13 Semiconductor Memory (continued) – ROM – read only memory • Nonvolatile • Used for permanent storage • Can be read but not erased or overwritten – Variations of ROM • PROM – Programmable read only memory • EPROM – Erasable programmable read only memory
- 48. 13 Magnetic Disk Storage • Most common form of secondary storage • Data is recorded on tracks in the form of tiny magnetized spots • Thousands of bytes recorded on each track
- 49. 13 Magnetic Disk Storage (continued) • Types of Magnetic Disks – Floppy disks – Zip disks – Hard disk drives
- 50. 13 Magnetic Disk Storage (continued) • Redundant arrays of independent disks (RAID) – Provides large capacities with high access speeds – Data are accessed in parallel over multiple paths from many disks – Fault tolerant – Storage area networks (SANs) • Fiber channel LANs that connect many RAID units
- 51. 13 Magnetic Tape Storage • Used as secondary storage • Also used in robotic automated drive assemblies • Lower-cost storage • Archival storage
- 52. 13 Optical Disk Storage • CD-ROM • CD-R • CD-RW • DVD • DVD-ROM • DVD-RAM
- 53. 13 Optical Disk Storage (continued) • Business applications – Image processing – Provide access to reference materials in a convenient, compact form – videos
- 54. 13 Discussion Questions • Do you agree with the statement: “The network is the computer”? • What trends are occurring in the development and use of the major types of computer systems?
- 55. 13 Discussion Questions (continued) • Do you think that network computers (NCs) will replace personal computers (PCs) in business applications? • Are networks of PCs and servers making mainframe computers obsolete?
- 56. 13 Discussion Questions (continued) • What trends are occurring in the development and use of peripheral devices? Why are those trends occurring? • When would you recommend the use of each of the following: – Network computers – NetPCs – Network terminals – Information appliances in business applications
- 57. 13 Discussion Questions (continued) • What processor, memory, magnetic disk storage, and video display capabilities would you require for a personal computer that you would use for business purposes? • What other peripheral devices and capabilities would you want to have for your business PC?
- 58. Real World Case 1 – City of Richmond 13 & Tim Beaty Builders • The Business Value of PDAs • What are the business benefits of PDAs for business applications? • What are the limitations of PDAs for business use?
- 59. 13 References • James A. O'Brien; George M. Marakas. Management Information Systems: Managing Information Technology in the Business Enterprise 6th Ed., Boston: McGraw-Hill/ Irwin,2004