Wednesday, November 21, 2007

Introduction to Computer

What are computers?

  • Problem solving tools that:
    1.Accept data
    2.Process data
    3.Store data
    4.Present results

  • Why is a computer so powerful?
    2.Accuracy (GIGO)

    What is Computing Literacy?
  • Learning how to use computer to benefit your life or work.
  • Required by most occupations.

  • Functions of a Computer
    1.Arithmetic - add, subtract, multiply, divide
    2.Comparisons - greater than, less than, equal
    3.Storage and retrieval

    What Computers Can Do?
    1.Data processing
    3.Design and Development
    4.Data Communication

    What Computers Cannot Do?
    1.Cannot identify a problem to be solved.
    2.Cannot identify and collect data.
    3.Cannot design software.
    4.Cannot identify the output needed to solve a problem.
    5.Cannot interpret and use information to solve a problem.

    Elements of an Information System

  • Equipment associated with computer
    1.System unit
    2.Communication device
    4.Input devices
    5.Output devices

    Keyboard, monitor, speaker

  • Software
    • Set of instructions that a computer understand (program)
    • Types of software
      • Application softwar
      • System software

    Application software
    Programs designed to perform specific tasks for users.
    1.Packaged software
    2.Custom software
    3.Shareware (distributed free for a trial period)
    4.Freeware (copyright)
    5.Public domain software

    System Software
    Interface = Programs that control the operations of the computer and its devices.
    • Operating system
      • Instructions that coordinate activities of hardware devices
      • Instruction to run application software
    • Utility programs
      • Perform a specific task.
      • Uninstaller, anti virus.

    User Interface
  • Controls how data and instructions are entered and how information is presented in the screen.
  • GUI allows interaction between users and software using visual images such as icons or button.

  • Software Development
    1.Computer programmers
    2.System analyst
    3.Programming language

    5 categories of computer users:
    1.Home Users
    2.Mobile Users
    3.Large Business Users
    4.Small Office/Home Office Users
    5.Power Users

    Common Computer Hardware Components - Monitor
  • Output device
  • Also called VDU (visual display unit).

  • Common Computer Hardware Components - Keyboard and Mouse

    Common Computer Hardware Components - System Unit

    Common Computer Hardware Components - Printer
  • Output device

  • Common Computer Hardware Components - Speaker and modem



  • Categories of Computer
  • Personal Computer ( Microcomputer)
  • Handheld Computer
  • Internet Appliance
  • Mid Range Server
  • Mainframe
  • Supercomputers

  • Personal Computer (Microcomputer)
  • 2 most popular series : IBM compatible and Apple Macintosh
  • Portable, small enough to fit on your lap
  • Generally more expensive than a desktop computer

  • Handheld Computer
    • Small computer that fits in your hand
    • Also called a palmtop or pocket computer
    • How do you input data with a handheld computer?
      • Stylus
      • Speech recognition
      • Handwriting recognitionld computer?
    What is a personal digital assistant (PDA)?
  • Provides personal organizer functions
  • 1.Calendar
    2.Appointment book
    3.Address book

    Internet Appliance

    What is an Internet appliance?
  • Computer whose main purpose is to connect to Internet from home.
  • Web TV is one example.

  • Mid Range Server
    • Use in medium-sized organizations
    • Cheaper than mainframe
    • Process faster than microcomputer
    • When it is uneconomical to use mainframes.
    • Organizations that use minicomputer:
      • Airlines
      • Domestic Banks
    • Examples:
      • IBM AS/400
      • NEC Astra


  • Huge computer
  • Can process large volume of data per second
  • Faster than minicomputer
  • More expensive than minicomputer
  • Can do intensive computational task

  • Supercomputer
  • Most powerful computer (very fast)
  • Most expensive
  • Used for running applications requiring complex and sophisticated mathematical calculations and applications.
  • Process several billions of instructions per seconds (bips)
  • Sensitive to temperature, humidity and dust.