There are many, many, different antivirus software packages available, and they all work in a very similar way: there is the software “engine” that scans the PC for viruses, and definitions files which contain data about the viruses themselves. Definitions files are constantly updated by the software companies as new viruses are discovered. By running updated antivirus software, most users should be able to easily avoid computer viruses.
The most common commercial product is the Symantec Antivirus package, which is widely accepted to be one of the best. It provides email and online protection, and is effective against almost any kind of virus the average user would encounter. There are also, however, many antivirus applications that are free for personal use, and for the average user they are completely adequate. Avast anti-virus is one of the most common free applications, and is generally considered to be effective protection against viruses.
Almost all antivirus software will do essentially the same thing, and so for the average user the issue is not so much choosing between antivirus software, but rather making sure that they have something installed and most important keeping the software up to date.
