1. Management Information Systems, Sixth Edition
Chapter 4:
Business Hardware

2. Objectives
List major hardware components of computers and explain their functions
Classify computers into major categories, and identify their strengths and weaknesses
Identify and evaluate key criteria for deciding what computers or related devices to purchase
Discuss the possible health hazards of computer use
Management Information Systems, Sixth Edition

3. Computer Hardware Components
Hardware: physical components of computers and related electronic devices
Consider software before hardware
Computer must handle four operations:
Accept data
Store data and instructions
Process data
Output data and/or information
Management Information Systems, Sixth Edition

4. Computer Hardware Components (continued)
In general, every computer has the following components:
Input devices
Central processing unit (CPU)
Internal memory
Storage
Output devices
Input devices: receive signals from outside of computer and transfer them into the computer
Management Information Systems, Sixth Edition

5. Computer Hardware Components (continued)
Management Information Systems, Sixth Edition

6. Computer Hardware Components (continued)
Central processing unit (CPU)
Accepts instructions and data
Decodes and executes instructions
Stores results (output) in memory
Internal (or primary) memory: stores data and instructions before and after CPU processes them
RAM: random access memory
ROM: read-only memory
Management Information Systems, Sixth Edition

7. Computer Hardware Components (continued)
Motherboard: circuit board containing the CPU and primary memory
Storage: magnetic disks, magnetic tapes, optical discs, DVDs, and flash memory
Allows permanent storage
Output devices: deliver information from the computer to the user
Monitors and printers are the most common output devices
Audio devices also deliver output
Management Information Systems, Sixth Edition

8. Computer Hardware Components (continued)
Bit: Binary digit
0 or 1
Byte: a standard group of eight bits
Most characters can be represented by a single byte
Computer memory and storage capacity are measured in megabytes (MB), gigabytes (GB), and terabytes (TB)
Management Information Systems, Sixth Edition

9. Computer Hardware Components (continued)
Management Information Systems, Sixth Edition

10. Classification of Computers
Computers vary in size and power
Classified by power
Power is determined mainly by processing speed and memory size
More powerful computers are more expensive
Management Information Systems, Sixth Edition

11. Supercomputers
Supercomputers: most powerful computers at any given time
Largest in physical size and most expensive
Designed for complex arithmetic calculations
Generally impractical for business purposes
Parallel processing: multiple processors running simultaneously
Also known as multiprocessing
Management Information Systems, Sixth Edition

12. Mainframe Computers
Mainframe computers: store large amounts of data and business transactions
Less expensive and less powerful than supercomputers
Often used by banks, universities, and insurance companies as a central computer
40-50% of world’s business data resides on mainframes
Use multiple processors
Management Information Systems, Sixth Edition

13. Midrange Computers
Midrange computers: often act as servers within organizations or through the Internet
Smaller and less powerful than mainframes
Serve hundreds of users that connect from personal computers
Use multiple processors
Management Information Systems, Sixth Edition

14. Microcomputers
Microcomputers: personal computers, notebook computers, and handhelds
Workstation: more powerful microcomputer used for CAD, CAM, and scientific applications
Power of microcomputers doubles about every two years
Management Information Systems, Sixth Edition

15. Computers on the Go: Notebook, Handheld, and Tablet Computers
Notebook (or laptop) computer: compact personal computer powered by rechargeable battery
New models include wireless technology
Personal digital assistant (PDA): handheld computer
Stylus: pen-like device used to enter data through a touch screen
Tablet computer: PC in the form of a thick writing tablet that recognizes handwriting
Management Information Systems, Sixth Edition

16. Converging Technologies
Technology convergence: building several technologies into a single piece of hardware
Prominent in handheld units
Commonly merged technologies include:
Cell phones
Television
Digital cameras
Digital sound recorder
MP3 players
Management Information Systems, Sixth Edition

17. A Peek Inside the Computer
Professionals must know about computer components to understand their power and capabilities
They use this knowledge to make good decisions in purchasing or recommending a computer
Management Information Systems, Sixth Edition

18. The Central Processing Unit
CPU has two units to store and process data
Control unit and arithmetic logic unit
CPU is a silicon chip with multiple circuits
Also known as microprocessor
Multicore processors: processors that combine two or more CPUs or “cores” on a single chip
Multithreading: processing more than one program, or several parts of a program, at the same time
Management Information Systems, Sixth Edition

19. The Central Processing Unit (continued)
Management Information Systems, Sixth Edition

20. The Central Processing Unit (continued)
Microprocessors are embedded with transistors
Transistor: a semiconductor that can represent binary code’s two states
CPU machine cycle:
Time period during which the CPU fetches, decodes, and executes each instruction
CPU clock: special circuitry on the processor that synchronizes all tasks
Clock rate: number of pulses per second
A machine cycle takes several clock pulses
Management Information Systems, Sixth Edition

21. The Central Processing Unit (continued)
Management Information Systems, Sixth Edition

22. The Central Processing Unit (continued)
Data word: maximum number of bits that the control unit can fetch from primary memory in a single machine cycle
Current microcomputers have words of 32 or 64 bits
Arithmetic logic unit: the part of the CPU that performs arithmetic and logical operations
Management Information Systems, Sixth Edition

23. Computer Power
Computer power depends on processing speed and memory capacity
Bus: electronic lines or traces used for communication inside computer
Throughput: number of bits per second that the bus can accommodate
MIPS: millions of instructions per second, a common measure of computer speed
Management Information Systems, Sixth Edition

24. Input Devices Computers must receive input to produce output
Input devices include machines and devices used to enter instructions and data into computer
Common input devices include:
Keyboard
Trackball
Microphone
Scanner
Management Information Systems, Sixth Edition

25. Keyboard
Keyboard: an input device that contains keys that users press to enter data
Includes letters, numbers, punctuation, and function keys
QWERTY: standard keyboard layout
Dvorak: keyboard layout that allows faster typing
Ergonomics: the study of the comfort and safety of humans in the workplace
Ergonomic keyboard: fits the natural position of forearms and prevents injury
Management Information Systems, Sixth Edition

26. Mouse, Trackball, and Trackpad
Mouse: input device that controls an on-screen pointer to facilitate point-and-click approach
Has one to five buttons for clicking, locking, dragging
Trackball: similar to mouse, but user manipulates a ball within the device to indicate movement on the screen
Trackpad: cursor movement is controlled by moving a finger over a touch-sensitive pad
Mice and similar devices can be wireless units
Management Information Systems, Sixth Edition

27. Touch Screen Touch screen: both an input and an output device
Often used for public applications, such as kiosks
Prevalent in handheld devices, GPS devices, and mobile phones
Allows the user to navigate and select by touching the screen
Management Information Systems, Sixth Edition

28. Source Data Input Devices
Source data input devices: copy data directly from sources such as bar codes, credit cards, and checks
Optical mark recognition devices detect positions of marks or characters
Optical character recognition (OCR) devices try to interpret handwritten and printed text
Magnetic-ink character recognition (MICR): detects magnetic ink on checks
Management Information Systems, Sixth Edition

29. Source Data Input Devices (continued)
Magnetic strips on credit cards store encoded data
Bar codes on products and packages store encoded information
Management Information Systems, Sixth Edition

30. Source Data Input Devices (continued)
Management Information Systems, Sixth Edition

31. Imaging Imaging: converts documents into images
Saves paper
More efficient retrieval and filing
Scanned document images can be:
Indexed and linked to relevant records in databases
Easily retrieved
Original paper documents can be destroyed after scanning
Management Information Systems, Sixth Edition

32. Speech Recognition
Speech (or voice) recognition: process of translating human speech into computer-readable data and instructions
Receives input from microphone and processes it with software
Speech-operated computers may increase noise level in offices and add distraction
Management Information Systems, Sixth Edition

33. Output Devices
Output device: a device that delivers results of computer processing
Popular output devices include:
Monitors
Printers
Speakers
In the future, smell output is possible
Management Information Systems, Sixth Edition

34. Monitors
Pixel (picture element): small dots that make up the images on a monitor
Cathode-ray tube: inner side of screen has layer of phosphoric dots that make up the pixels
Electron gun receives instructions from computer and sweeps the pixels
Flat-panel monitor: advantages include lower power use, sharper images, and slim profile
Liquid crystal display (LCD) monitor: uses a liquid crystal filled screen
Management Information Systems, Sixth Edition

35. Monitors (continued) Monitor price depends on:
Size, measured as the diagonal length of the screen
Brightness
Contrast ratio (the higher the better)
Pixel pitch (closeness of the pixels)
Resolution: a measure of picture sharpness
Number of pixels in the width and height of the screen
Management Information Systems, Sixth Edition

36. Printers Nonimpact printer: does not mechanically impact the paper
Laser printer is most common in business
Others include ink-jet and electrothermal printers
Speed is measured in pages per minute (ppm)
Density measured in dots per inch (DPI)
Impact printers: reproduce image by using mechanical impact
Dot-matrix printer: tiny pins strike ink ribbon against paper
Management Information Systems, Sixth Edition

37. Storage Media Data must be stored on nonvolatile medium
Data is retained even when the storage device is not connected to electrical power
Storage devices differ in the technology used to maintain data and physical structure
Evaluate storage devices by comparing:
Cost
Capacity
Access speed
Access mode
Management Information Systems, Sixth Edition

38. Modes of Access
Sequential storage: data is organized one record after another
Must read through all records that are stored prior to the desired record
Direct access: records are organized by physical address on the device
A record can be accessed directly (randomly)
Flash drives: small storage devices that connect via universal serial bus (USB)
Direct access storage media is the only practical way to organize and query databases
Management Information Systems, Sixth Edition

39. Modes of Access (continued)
Management Information Systems, Sixth Edition

40. Magnetic Tapes
Magnetic tapes: similar to tapes used in tape recorders and VCRs, usually as cartridges
Provide lowest cost (bytes per dollar)
Can back up all data
Takes a long time to copy from tape
Tapes are unreliable after long periods of time or usage
Management Information Systems, Sixth Edition

41. Magnetic Disks Magnetic disk: most widely used storage medium
Includes hard disks and floppy disks
Hard disk: stack of several rigid platters installed in the same box that holds the CPU
Stores up to one TB of data
External hard disks connect to computer through USB port
Management Information Systems, Sixth Edition

42. Optical Discs
Optical disc: recorded by treating the disc surface to reflect light in different ways
Two basic categories of optical disk:
Compact discs (CDs)
Digital video discs (DVDs)
Compact discs: available as read-only, recordable, and rewritable
DVDs: store 4.7 GB per side
Optical discs are slower than hard disks
Management Information Systems, Sixth Edition

43. Optical Tape
Optical tape: uses same technology as optical discs to store and retrieve data
Bits are organized sequentially, similar to magnetic tape
Mainly used in digital video camcorders
Management Information Systems, Sixth Edition

44. Flash Memory
Flash memory: rewritable memory chip that holds content without power
Consumes very little power
Does not need a constant power supply
Fast access times
Relatively immune to shock or vibration
Available as memory card and USB drive
Solid state disk: storage media that does not have latency time
Management Information Systems, Sixth Edition

45. DAS, NAS, and SAN
Direct access storage (DAS): disk or array of disks or tapes directly connected to server
Easy to deploy and manage
Does not relieve any of server’s workload
Network-attached storage (NAS): device designed for networked storage
Includes both the storage media and the software to manage it
Offloads processing from the server
Highly scalable
Management Information Systems, Sixth Edition

46. DAS, NAS, and SAN (continued)
Storage area network (SAN): a network fully devoted to storage and transfer of data
Managed separately from the rest of the LAN
May combine DAS and NAS devices
Can transfer larger blocks of data at higher speeds
Expensive and complex to manage
RAID: redundant array of independent disks
Used by DAS, NAS, and SAN
Fault-tolerant: can continue even through disk failures due to redundancy
Management Information Systems, Sixth Edition

47. Business Considerations in Evaluating Storage Media
When purchasing storage devices, managers must consider:
Purpose of data storage
Amount of data to be stored
Required speed of data storage and retrieval
Unit space and portability of the device
Cost
Reliability and life expectancy
Trade-offs
Management Information Systems, Sixth Edition

48. Business Considerations in Evaluating Storage Media (continued)
Management Information Systems, Sixth Edition

49. Considerations in Purchasing Hardware
Companies must consider the following when selecting equipment to purchase:
Power of the equipment (memory size, capacity, speed)
Expansion slots and ports (sockets used to connect computer to external devices)
Monitor type and resolution
Ergonomics
Compatibility with existing hardware, software, and networks
Management Information Systems, Sixth Edition

50. Considerations in Purchasing Hardware (continued)
Considerations (continued):
Hardware footprint (physical size of equipment)
Reliability of vendor
Warranty policy and post-warranty support
Power consumption and noise
Cost
Backward compatibility: the capability to work with older hardware or software
Management Information Systems, Sixth Edition

51. Management Information Systems, Sixth Edition

52. Scalability and Updating Hardware
Scalability: resources can be expanded or upgraded to provide increased power
Not all hardware is scalable
Leasing hardware is a valid option to avoid short useful lifetime of hardware
Management Information Systems, Sixth Edition

53. Summary Understanding hardware is important for purchasing decisions
Computers are classified according to power
All computers have a CPU to process instructions
Clock rate measures the speed of a CPU
Data word: the number of bits the computer can process in a single cycle
Management Information Systems, Sixth Edition

54. Summary (continued)
Computer power: measured by its speed, memory size, and number of processor cores
RAM: volatile memory that forms the largest part of computer’s memory
ROM is nonvolatile; it does not require power
Imaging devices help process text and graphics
When evaluating external storage, consider transfer rate, capacity, portability, and form of data organization supported
Management Information Systems, Sixth Edition

55. Summary (continued) Data is organized sequentially on tapes
Direct access storage devices such as RAM, magnetic disks, and optical discs allow random access
Databases require direct access storage devices
When purchasing hardware, professionals should consider cost, power, scalability, and compatibility
Information technology may pose health risks such as carpal tunnel syndrome
Management Information Systems, Sixth Edition