Has My PC Got a Virus ?

What is a virus? The term broadly describes any program that tries to hide a malicious function or spread copies of itself on to as many computers as possible.

Believe it or not most viruses are benign, displaying a message or picture at a specific time. There are some malignant viruses that can cause damage to your files and programs. Most viruses in circulation fall into six key classifications:

1. Worm - a self contained program that can spread functional copies of itself to other computer systems.

2. File Infector - attaches itself to ordinary program files, it usually ends in exe or com.

3. Trojan Horse - Noramlly a non-replicating program, designed to perform malicious damage, such as destroying all word processing documents.

4. Boot Sector Infectors - These attach themselves to the boot sector of a disk, either on your hard drive or on any floppy disk that you insert into your floppy drive.

5. Master Boot Record Infectors - Infect the master boot program preventing it from starting in the usual way, for example constantly restarting.

6. Multi-partite viruses - this can infect both the master boot records, or files and disk boot sectors.

How does your PC pick up a virus? They don't just occur, they are introduced to your PC by an outside party and can be avoided if you take appropriate precautions.

Downloading files from the internet or receiving e-mail can put you at risk of virus infection. Contrary to popular opinion it's not generally possible to contract a virus by simply reading an e-mail message. The damage is done by executing files that are attached to your message without first checking for viruses. This could also occur by importing information from floppy disk files that were created on an infected PC.

How do I know if I have a virus? Generally, some of the symptoms might be a discrepancy in the amount of memory you have, running out of hard drive space unexpectedly, programs running or loading slowly, unidentified files appearing, and unexpected crashes or failure to load. These symptoms could also be due to a number of common technical problems, don't automatically assume that you have a virus the moment anything looks out of the ordinary or slows down.

The best way to ensure protection from viruses is to install a specialised piece of software often referred to as anti-virus software or a virus checker. This continually scans for possible problems and alerts you before they can inflict any damage.

Source: http://goo.gl/8oyFM