HARDWARE AND SYSTEM

• Hardware


  The physical components of a computer
• System Technology Basics


  The fundamental elements that make the functioning of electronic equipment smooth and faster
• Basic elements of a computer system

  • Hardware
  • Software
  • Programs
  • Data
  • Connectivity
• Basic components of a computer system

  • Input
  • Output
  • CPU (Central Processing Unit)
• Components of a computer system

  1. Take input

  2. Store data

  3. Process data

  4. Output information

  5. Control the workflow
• Input devices


  Devices that allow the user to feed data to the computer
• Keyboard


  An input device that takes letters or characters from the user, processes it, and then shows the output on the monitor screen
• Types of keys on a computer keyboard

  • Alphanumeric keys
  • Punctuation keys
  • Navigation keys
  • Function keys
  • Control keys
  • Special keys
  • Toggle keys
• Mouse


  A handheld hardware input device that controls a cursor in a GUI (graphical user interface) for pointing, moving, and selecting text, icons, files, and folders on your computer
• Numeric keypad


  Used for navigation when the keyboard is off
• Scroll


  Used to scroll through a page, not widely used on keyboards
• Output Devices


  Devices that transform the output from the computer into a form understandable by the users
• Output Devices

  • Monitor
  • Speaker
  • Printer
• Monitor


  • Television-like screens that provide the user interface in the form of displaying text, numbers and images
  • Can be monochrome or coloured
• Speaker


  • Can produce verbal output (sound)
• Types of Printers

  • Character printer
  • Line printer
  • Page printer
• Dot Matrix Printer


  • Prints one character at a time
  • Produce dotted-output because of the pins on the print head
  • Speed is measured by CpS (Character per second) 50-600cps
  • Produces a lot of noise
  • Uses ribbon as an ink
• Inkjet Printer


  • Non-impact printer
  • Quiet when working
  • Gives better quality
  • Available in black/white and in color
• Graphic Plotter


  • Used for large format media
  • Graphs, maps, billboards, tarpaulin
• Line Printers


  • Drum printer
• Drum Printer


  • Uses powder as an ink
  • Available color: Grayscale
• Page Printers


  • Laser printer
  • Magnetic Printer
• Laser Printer


  • High-end printer
  • More expensive than inkjet printers
  • Available color: Grayscale
• Magnetic Printer


  • Drum coated with magnetic material that capture the image of the page to be printed
  • Use thermal papers
• Central Processing Unit (CPU)


  The brain of the computer that executes all types of data processing functions, saves data/intermediate results/instructions, and controls the operation of all parts of the computer
• CPU


  • Has 3 components: Memory/Storage Unit, Control Unit, ALU (Arithmetic Logic Unit)
• Memory/Storage Unit


  Stores instructions, data, and intermediate results, and passes data to other parts of the computer when required
• Primary Memory


  • RAM (Random Access Memory) - Volatile, temporary holding area for data, application program instructions and operating system
• Secondary Memory

  • Magnetic disk - Direct access, made of rigid materials or symmetric plastic material
  • Magnetic tape - Serial access storage medium, can store large volume of data at low cost
  • Optical Storage - Information is written to or write from an optical disk or tape using laser beam
  • Solid state storage - Sometimes called flash memory, erasable, re-writable
• Control Unit


  Manages the operations of all parts of the computer but does not carry out any calculations or comparisons or actual data processing operations
• ALU (Arithmetic Logic Unit)


  Consists of Arithmetic Section to execute arithmetic operations, and Logic Section to execute logic operations