If your computer is not running a virus protection software package, not only are you susceptible to an attack, you are also likely to enable the spread of the virus through your machine.

Furthermore, even if you have installed the software, but haven't updated the software on a regular basis, you are just as vulnerable as not having it at all.

So, let's start at the beginning. It is important to understand that a virus is nothing more than a software program similar to Microsoft Word or any other program installed on your computer. The virus is programmed to cause some kind of harm to your computer when it runs.

Generally what happens is, some person or group develops the virus with some malicious intent in mind. And, since their motive is to cause as much harm as possible, they write their program in a way to operate on as many computers as possible. In other words, they attack weaknesses in the Microsoft Windows operating system, usually those running Outlook or Outlook Express for e-mail.

Odds are, you are running that combination on your computer because Microsoft has such an overwhelming market share on the personal computer industry.

So the next thing the virus developers do is send out their program through e-mail to as many addresses as they can find. Once the message arrives, many e-mail programs will try to run or install the program automatically ˜ a handy feature Microsoft built in for you that is easily taken advantage of.

If not, the developers use other tricks or inviting wording that makes us want to click on it. And, once we do, we unleash the virus on our own.

Now that the virus is installed and done the damage on your machine, it goes into phase two, which is to spread itself on to more computers, using your computer in the process. One popular method is to send itself to everyone in your address book, thus attacking all your friends and colleagues.

That leaves you with an infected computer, and many upset friends who now also have infected computers. At that point, you most likely need to call in a professional and have your computer disinfected or wiped completely clean, depending on the extent of the damage.

This leads me back to importance of prevention and hopefully explains why it is so important for everyone to have up-to-date virus protection running on their personal computers.

Fortunately this is easy to do with today's software packages, because they are aware of these problems and the newest versions all have update capabilities built right in.

There are two popular software packages to consider for your computer. Both are approximately $50 and have very similar features.

The first is Symantec's Norton AntiVirus 2004 (http://www.symantec.com). This package automatically removes viruses, worms and Trojan horses.

Their LiveUpdate downloads new virus protection updates automatically to protect against the latest threats. And, Worm Blocking and Script Blocking can detect new threats even before virus protection updates are created for them.

The second option is McAfee's VirusScan (http://www.mcafee.com). VirusScan automatically checks for virus updates and software updates (included free with your one-year coverage), so your protection is always current.

After you have installed one of these two packages it is OK to feel a little more confident in your system's security, but it is important to always be smart about the files coming into your e-mail. Any time you see an attachment, be very cautious and never open it unless you are absolutely sure that it is a legitimate file you are expecting from a reliable source.