Tag Archives: Virus

FAQ: What is a Virus

A virus is a self replicating program that can destroy or cause damage to data stored on a computer system.

A virus program must be executed in order to infect a computer system. Viruses can attach themselves to other programs in order to ensure that this happens. Viruses are spread through file downloads or infected storage media such as floppy disks.

Common symptoms of virus infection:

  • Displaying unwanted messages
  • Unusual visual or sound effects
  • Loss of data from a storage medium
  • Computers restarting unexpectedly
  • Unwanted generation of e-mails

Description of utility programs – virus checker

A virus checker or Anti-Virus Software will scan files and check for traces of a virus and is then able to remove the virus.

Anti-virus software works in two modes: stand-alone and memory resident. In stand-alone mode the software works like any other program. You start it and point it at a file, directory or disk to check the files for viruses.

In memory-resident mode the anti-virus software stays running on your system at all times. Whenever a file is used the software will check it for viruses. As well as checking files, most anti-virus software will also check e-mails and web pages.

Computer Software – Malware

Today was all about malware, we covered the following section of the arrangements document using the Scholar notes and these PowerPoints.

  • Classification of viruses by type of file infected:
    • file virus
    • boot sector virus
    • macro virus
  • Description of the following virus code actions:
    • replication
    • camouflage
    • watching
    • delivery
  • Distinction between
    • a virus
    • a worm
    • a trojan horse
  • Description of anti-virus software detection techniques:
    • use of checksum
    • searching for virus signature
    • heuristic detection
    • memory resident monitoring

You can find the revision note here and there are links at the side of the page.