Anti-Virus

What is Anti-Virus?

"Anti-virus" is protective software designed to defend your computer against malicious software.

Malicious software, or "malware" includes: viruses, Trojans, keyloggers, Backdoors,hijackers, dialers, and other code that vandalizes or steals your computer contents. In order to be an effective defense, your anti-virus software needs to run in the background at all times, and should be kept updated so it recognizes new versions of malicious software.

Once these viruses have been identified, your anti-virus program will then either neutralize (often by putting in "Quarantine") or delete the virus so that it cannot harm your computer.

Identification methods

There are several methods which anti virus software can use to identify malware.

Signature based detection is the most common method. To identify viruses and other malware, anti virus software compares the contents of a file to a dictionary of virus signatures. Because viruses can embed themselves in existing files, the entire file is searched, not just as a whole, but also in pieces.

Heuristic-based detection, like malicious activity detection, can be used to identify unknown viruses.

File emulation is another heuristic approach. File emulation involves executing a program in a virtual environment and logging what actions the program performs. Depending on the actions logged, the anti virus software can determine if the program is malicious or not and then carry out the appropriate disinfection actions.