Antivirus Software

Antivirus software
Antivirus software (sometimes spelled Anti-Virus or anti-virus with the hyphen) are computer programs that attempt to identify, neutralize or eliminate malicious software. The term "antivirus" is used because the earliest examples were designed exclusively to combat computer viruses; however most modern antivirus software is now designed to combat a wide range of threats, including worms, phishing attacks, rootkits, Trojans, often described collectively as malware.

Virus scanners
Antivirus scanning software, or a virus scanner, is a program which examines all files in specified locations, the contents of memory, the operating system, the registry, unexpected program behavior, and anywhere else relevant with the intention of identifying and removing any malware.

Typically two different approaches are used to identify malware, often in combination, although with an emphasis on the virus dictionary approach.

* examining (scanning) files, etc., for known viruses matching signatures in a virus dictionary, and
* identifying suspicious behavior from any computer program which might indicate infection. This approach is called heuristic analysis, and may include data captures, port monitoring and other methods.

Network firewalls prevent unknown programs and Internet processes from having access to the system protected; they are not antivirus systems as such, and make no attempt to identify or remove anything, but protect against infection, and limit the activity of any malicious software which is present by blocking incoming requests on certain TCP/IP ports.