Computer anti-virus software

An anti-virus is a computer software program that is used to identify harmful computer viruses, worms, spyware, Trojans and d malicious software (malware), prevent computer infection by these threats and to remove found threats   from the computer by scanning all the files in the computer hard disk. Also  a good computer antivirus program helps to protect the computer  from  keyloggers which track each and every computer keystroke so as to steal account information and passwords, phishing scams(programs appearing as legitimate sites but are attempting to gather user’s sensitive information), email-borne threats, and  rootkits(take computers control without users knowledge)  .

Description of how anti-virus software works

The program uses two techniques to attain its objectives:

First one is by using virus dictionary to inspect all the files in the computer hard disk for viruses which are known. The anti-virus author identifies a dictionary containing known viruses which is used to examine a file and when a code inside the file matches any virus code in the dictionary, the program deletes the file, repairs the file by removing the virus only or quarantines it making the other programs unable to access the file. For this approach to be successful the user must download online updated entries of the virus dictionary periodically either daily or weekly. These updates come from the anti-virus authors who update their dictionaries using use new viruses s identified from new infected files.

Using dictionary-based anti-virus program allows immediate detection of viruses as the files are examined as computer either opens, closes or creates the files and also when they are e-mailed. One can also schedule the software to scan the files at regular intervals.

The second approach is the suspicious approach which checks the behavior of all programs and alerts the user when a suspicious behavior occurs for instance, when data is tried to be written on an executable program by one or more programs. The suspicious approach unlike the dictionary approach thus offers protection against very new viruses that are not known and not existing in the virus dictionaries.

Installation of antivirus.

This is typically a very simple and quick exercise as it contains simple setup procedure and it is user friendly even to beginners.

 Updates for the antivirus.

As new viruses are identified regularly, antivirus softwares mostly   have automatic updates built into them by the software authors. Since many consumers search for programs having free updates for a certain period before they are required to purchase a subscription or a new version it is of paramount importance to include this feature in ones program.