There are many different types of viruses that all perform various negative actions. There are: Resident; Direct Action; Boot Sector; Macro; Polymorphic (worms); Trojans; Adware and so many more. Each one has its own function and personality. For example, some are destructive and will erase your data. Others will corrupt your files, and when transferred to another computer, it will then corrupt that computers files. There are those that steal your information, and others that capture all the keystrokes you type and send them to the issuer of the virus. Some corrupt your web browser and will take you to targeted advertising websites, and others disable your internet completely. There are so many, and each has its own special brand of chaos.
Most antivirus programs are excellent at finding viruses it has logged in its’ definition database, and is fairly good at guessing if a file looks suspicious. A definition database is a list of strings of information that constitutes the makeup of a virus. For instance, lets assume that 1×43#%1AbC is a string that represents a virus. In a very simplified explanation, the antivirus program will look for that string of data when you use a file. If it detects that sequence in the file, it will assume it’s a virus. Let’s say, that today the string 1×43#%AbC represents a virus, but the devious virus programmer has created a new strain of the virus and it looks like this 1×43#%XyZ. Unless you keep the virus definitions up-to-date, you will be lagging behind. You antivirus program will not think that the new string is a virus because it does not recognize the new strain (definition). How can you make you computer safer? Make sure you are getting your updates as soon as they become available. Most antivirus programs have a “Get Updates” button that you can press to check if new definitions are available.
Simply updating your definitions is not good enough. I’ve seen (too many times) systems that are running antivirus programs that are more than two years old. This is a major cause of concern. Even though you may have been doing your definition updates on a daily basis, the antivirus program will not know of any new viruses that have arrived on the scene. Suppose that last year there were 3 viruses called “A”, “B” and “C”. By performing your definition updates, you will be protected from the various strains of those viruses, such as “A-1″, “A-2″ or “A-3″. However, suppose there is a new virus “D” (be very afraid!). Your antivirus will not be able to detect this type of virus or its strains because it does not have the mechanics (or knowhow) to do it, since this virus works completely differently to any existing virus. Therefore, I highly recommend that you update the actual antivirus software when new versions become available, in order to keep up-to-date with new virus types.
Most viruses these days do not come via email. Approximately 3% of viruses are delivered this way. The main source of infection will come from visiting websites that are infected, or by downloading software that contain Trojan viruses. A Trojan virus is a program that hides a virus inside of it. For instance, suppose you downloaded an infected game of solitaire. The installation procedure will install the real game, but at the same time it will also install a virus without your knowledge. Protect yourself by not going to websites that seem suspect, or downloading software unless you know it’s clean! Most infected websites these days generally have viruses that are malware (viruses that tend to damage or disable a computer), or spyware, which is software that self-installs on a computer and then enables it to steal various information from that computer such as passwords, internet use and more.
To avoid this, try to get an antivirus program that not only searches for known viruses, but also protects you when surfing the web. Currently the company AVG has a free (for personal use) antivirus software that also checks websites when you Google them, and determines if there is content on the web page that seems suspect. Most anti-virus programs don’t look for spyware unless they come bundled with anti-spyware programs.
There are many other programs available that can detect if data is being procured from or passed to your computer without your knowledge. Free programs like “ZoneAlarm Free Antivirus + Firewall” is just one of them.
There are great email scanners that let you wipe out any questionable email before they get to your computer. A great one called “MailWasher Pro” from http://www.firetrust.comworks extremely well. It does a fantastic job at getting rid of unwanted or suspect emails.
You can feel a lot safer if you use a combination of an antivirus program like “AVG antivirus”, along with an antispyware app, a cleaver firewall blocker like “ZoneAlarm” and an email scanner like “MailWasher Pro”. You may still get a virus, but with the right setup you will drastically cut down on your chances of infecting your computer.
If you don’t have an antivirus program installed you are just asking for trouble! Stay happy by keeping your computer healthy by updating your antivirus on a regular basis.