ICT Unit 1

ICT Unit 1

1. Types of computers

   • MainFrame computers
     • extremely large computer
     • used in organisation e.g. banks or government departments
     • Able to do very big jobs which make use of their large memories and fast speed
     • Are large and take up the whole room
     • Expensive to operate and maintain
   • Desktop or PC
     • Monitor, keyboard, mouse and processor and storage
     • Spare parts are often cheap because they are standardised
     • Lack of portability- heavy and must be powered all the time to work
   • Laptop or Notebook
     • All the components are together
     • very portable
   • Tablet
     • like a laptop but smaller
     • the interface is touch screen where as a laptops its not
     • quick to turn on
     • touch screen typing can be difficult
     • Thousand of downloadable applications and for free
     • Cannot make phone calls

2. Hardware and software

   • Hardware
     • Monitor
     • Mouse
     • Speakers
     • Keyboard
     • Printer
     • Memory chips
     • Motherboard
   • Software
     • system software
       • Programs and files that make up the computer's operating system
       • e.g. software to connect with the printer, that controls the way the screen appears
     • Applications software
       • Programs allow users to write letters, solve problems,
       • e.g. word processing, presentation software,spreadsheet

3. Main components of a computer

   • motherboard
     • The main circuit board
     • Holds the crucial electronic components of the system
       • e.g. the CPU and the main memory
   • Main memory
     • Internal memory
     • Central memory
     • Primary memory
   • RAM ( random access memory)
     • the internal memory chip where data is stored temporarily when applications are running
     • can be both read and written to
   • Input and output devices
     • Input device
       • those that are used to put information into a computer
       • e.g. Keyboard, mouse and webcam
     • Output device
       • those that take information from the computer for other uses
       • e.g. monitor, printer and speakers