ANTI-VIRUS SOFTWARE- HOW IT WORKS.

An Anti-virus software is a set of instructions designed to run on a computer in order to scan/detect, clean, heal, remove or quarantine computer viruses and any other suspicious software programs. When an Anti-virus program detects any infection from known viruses, it removes, deletes, repairs or quarantines the infected files.

Examination of files for viruses is achieved through an internal virus dictionary. Any suspicious program on your computer might also be an indication of infection which your Anti-virus program will treat as unwanted. The first thing your Anti-virus program does when you command it to run on your computer is that it examines the files and compares the results with those in the virus definition database or dictionary. What your Anti-virus program is doing is just to check for known virues through the dictionary. If the code in the scanned files matches any in the dictionary, it deletes, repairs or quarantines the files. Quarantine is like a chest where the infected files are kept pending further action from the user. This is done in order to isolate the infected files from the healthy ones. This action further controls the spread of the virus from infecting more. Though this sounds cool there is a challenge from more cunning Virus programs which disguise themselves in a way that they match the code in the virus dictionary.

The suspicious program monitoring is achieved through monitoring of how your computer programs run or behave. When a program attempts to modify the normal procedure of the excutable programs, the Anti-virus will send a signal to warn the user of an impending danger.

For you to keep your computer running effectively, constant update of your anti-virus software is needed. This also checks and updates the virus definition database you currently have with the latest ones.

Reference:

1. http://www.technet.microsoft.com