Functions of an Operating System

Functions of an Operating System

1. Manages resources and providing user interface

2. Manages Peripherals e.g. input and output devices

3. Manages printing using spooling

   • Data is stored on hard disc/in memory/stored in a queue
   • Document is printed when printer is free/in correct order

4. Manages backing storage

   • Ensures data is stored and can be retrieved correctly from any disk drive
   • Creates and maintains filing systems
     • FAT
       • File Allocation Table
     • NFTS
   • Organises files in a hierarchical directory structure

5. File Compression

   • The amount of data is reduced and the file is mad smaller
   • Definiton
     • The process of making a file size smaller
   • Used to save disk space

6. Disk defragmentation

   • Fragmented files are split up and stored on different parts of the disk
   • Will slow down access speed
   • Definition
     • the process of files parts being physically rearranged (into the order required for access)
       • Reorganising
       • moving
       • re-ordering

7. Manages Memory (RAM)

   • Ensures that ...
     • programs/data do not corrupt eachother
     • all programs and data including itself is stored in a proper memory location

8. Manages processes

   • Ensures that...
     • different processes can utilise the CPU without interfering and crashing with one another
     • all tasks appear to run simultaneously

9. Manages Security

   • Allows users to..
     • Create and delete user accounts
     • Logon
     • Change passwords

10. Providing a user interface

    • provides a CLI
    • Allows users to have more than one window open
    • provides a GUI
    • provides users with error/help messages
    • allows customisation of interface
    • allows user to switch between tasks
    • allows access to system setting as hardware