Operating Systems

Operating Systems

1. GUI

   • GRAPHICAL USER INTERFACE
   • Contains graphics and icons- commonly navigated by a computer mouse
   • Easier to use than CLIs and are the usual type of OS
   • PARTS OF A GUI
     • POINTER
       • Symbol that appears on display screen. Move it to select objects and commands. Moved by a mouse of trackball
     • DESKTOP
       • Area on display screen where icons are grouped
     • ICONS
       • Small pictures that represent commands, files or windows
     • MENUS
       • Run commands by selecting a menu choice
     • WINDOWS
       • Divide the screen. In each window a different program can be run
     • D WIMP

2. CLI

   • COMMAND-LINE INTERFACE
   • Require keyboard commands
   • Can be complicated so often shortened using appreviations
   • Typing commands take time and learning them aswell. CLI is less user friendly

3. DIFFERENT OS TYPES

   • MAC OSX
   • Linux
   • Windows
   • UNIX
   • Android
   • IOS

4. What does it do?

   • Transfers data between memory locations of CPU
   • Produces visual display for the monitor
   • Controls peripherals such as printers and input devices
   • Provides an environment where apps can run

5. MULTI TASKING

   • Early computers could only do one task at a time
   • Modern ones can now cope and perform many tasks at a time
   • E.g Listening to radio in one tab and writing a power point in the other

6. MULTI USER

   • Most modern OS allow multiple users to use them
   • A mukti user OS can allow several people to use the same computer without having to reboot it

7. SECURITY

   • Must prevent users from clashing or the wrong user gaining access to another's private files
   • It does this by dividing memory into sections and keeping a log of processes are using each page to prevent conflict
   • Some files are stored centrally and are available to all users