There are a number of companies that provide software solutions to virus, Trojan, and internet worm attacks. It can be really confusing when you compare three different software packages from five different companies trying to find the one that is right for you. With that in mind, there are several very important things that you need to consider when choosing antivirus software:

1) How often/fast are the virus definitions updated. You want the answer to be "As soon as a new threat is found".

2) Are the virus definitions updated automatically by the software? You want the answer to be "YES".

3) Can you configure the software to check for updates every time you go online? You want the answer to be "YES".

4) Is the software "smart" so that it can find viruses it doesn't even know about yet? You want the answer to be "YES".

5) Can it scan incoming and outgoing email automatically? You want the answer to be "YES".

6) Can you configure it once to perform automatic scans of your entire computer on a regular schedule? You want the answer to be "YES".

7) Does it provide a way to 'clean out' any viruses etc. that are found? You want the answer to be "YES".

8) Are upgrades to the software package performed automatically, regularly, and at no cost? You want the answer to be "YES".

There are a few major players in the field that you should know about in order to make an informed decision about which antivirus software solution to buy and use. There are Norton Antivirus, Trend Micro's PC-cillin, and McAfee Antivirus. Sophos and Grisoft's AVG are also very god choices. All of the top antivirus solutions will provide each of the eight points above (and more).

There are quite a few smaller players on the market as well. In many cases they are quite good. However, most of the smaller players in this market don't have the resources (yet) to keep up with constantly changing virus threats. For now I would recommend staying away from them. Not because they are poor products, but simply because they aren't able to consistently provide each of the eight requirements above.

The first few days after a new virus appears are often when it can do the most damage. The sooner you get an update the better. The big 3 will provide automatic updates to new threats usually within days of a new virus being found. Sophos and AVG are similar. Smaller players may take several days to provide updates, which are often not automatic.

This should be enough basic information to help you on your way to choosing a good antivirus software. If you'd like to learn more first, there is plenty to read at http://www.antivirus-report.com/antivirus-software.html