Protecting your computer against Viruses & Worms

Published 12/05/2004 16:18   |    Updated 23/04/2008 14:06
Protecting your computer against Viruses & Worms.

Computer Viruses

A computer virus is merely a program that attaches itself to another program or data file in order to spread and reproduce itself without the knowledge of the user.


The effects of these viruses can vary widely depending on what they were designed to do. Some viruses are annoying but cause no significant damage. Others can be quite harmful and can even erase data or corrupt disks.


As viruses are designed to hide their presence in legitimate programs or data files, viruses are usually spread from computer to computer by individuals who are unaware they are doing so. The main methods by which viruses are generally transmitted include:

  • Attachments to email messages.
  • Files downloaded from the Internet.
  • Using infected disks or compact disks (CDs).

Although some viruses are not dangerous (for example some of the more benign viruses may simply pop up harmless, if annoying, slogans). However, sophisticated and damaging viruses are becoming more and more widespread.

Some of the serious effects of a virus can include:

  • Loss of data and files.
  • Decrease in network performance.
  • Confidential data being emailed to someone else, or even



Computer Worms

Worms are independent programs that reproduce by replicating themselves across systems.

Although not strictly speaking a virus, worms can either damage data directly or more commonly degrade system performance by using up too many of your computers resources.


The two main differences between viruses and worms is that a worm operates as a standalone program whereas a virus usually attaches itself to another program. A virus can also spread through any medium whereas a worm operates through networks. Perhaps the most famous example of a worm is the "ILOVEYOU" worm which infected an estimated 10 million computers.


Tips to protect yourself online


NEVER download files or information from people or sites which you aren't sure about. Even if the file comes from a friend, you still must be sure what the file is before opening it. When in doubt, it is recommended that you scan the attachment with a fully updated anti-virus program.


Beware of hidden file extensions! In some operating systems, the filename extensions such as .jpg are not displayed by default. It is recommended that you should configure your operating system to show file extensions.


NEVER use features in your programs that automatically retrieve or preview files. Those features may seem convenient but may make your computer more vulnerable to receiving unwanted software.


Don't be lulled into a false sense of security just because you run anti-virus programs. These alone may not sufficiently protect your system against new viruses and trojans even when fully up to date. Effectively securing your system requires a combination of the recommendations outlined on this Web site.


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