You should be able to…

  • Explain the need for the following functions of an operating system: user interface, memory management, peripheral management, multi-tasking and security
  • Describe the purpose and use of common utility programs for computer security (antivirus, spyware protection and firewalls), disk organisation (formatting, file transfer, and defragmentation), and system maintenance (system information and diagnosis, system cleanup tools, automatic updating)
Antivirus
-Scans the computer periodically to check if any software has been installed which contains code that may harm the computer
-Removes/quarantines these programs / notifies the user
-Prevents these programs from being installed
-Protects the computer by preventing important files (eg the boot sector or operating system) from being changed
Disk defragmenter
-Moves (parts of) of files around so that all parts of a file are stored together (allowing files to be accessed more quickly)
-Free space is collected together (allowing large files to be saved easily)
System information
displays important data about the current state of the computer e.g. temperature, free memory, network speed, % processor used
Diagnosis
attempts to detect/resolve items that are not working correctly e.g. missing drivers, network connection
System cleanup
-Searches for and deletes files/programs which are no longer used eg deletes temporary files installation files
-Deletes settings / registry values which are no longer used
Automatic update
-Checks on the (software manufacturer’s site on the) Internet for newer versions of programs which are installed
-If found it downloads and installs the software updated software
  • Discuss the relative merits of custom written, off the shelf, open source and proprietary software
Custom written
Software is made especially for a specific user
Off The Shelf
-Off the shelf software is available for anyone to acquire and use/ is commercially available
-Tried and tested / less likely to contain bugs
-Costs less than custom-written
-Developer not available to make adjustments necessary
-May contain features not needed by the user
-May not contain features which are needed by the user
Open Source
-The source code is distributed with the software
-The customer can modify the source code
-The customer can redistribute the source code (with the same licence/restrictions)
Proprietary Software
-Source code not made available/ Only compiled code is published
-Licence restricts the copying/modifying/distribution of the software

TOPIC OVERVIEW (Test your Knowledge (1) (2) (3))