An easy to use firewall to keep programs on the internet from accessing your computer without permission and to keep any program on your computer from accessing the internet without permission.
I discovered a Matrix infection when ZoneAlarm alerted me to the fact that a new program was trying to access the internet. I checked it out and found my Virus detection database was out-dated and I'd let in a virus. A virus that was trying to talk to his friends and cause more damage. ZoneAlarm stopped the virus and as a result alerted me to the exist of the virus.
I've also detected a couple of programs with embedded Spyware. After installing the programs they tried to phone home with information about my computer. ZoneAlarm alerted me to this and I was able to eliminate the Spyware using the OptOut Utility from Gibson Research Corporation. That was fun.
I've also had the pleasure of watching ZoneAlarm stop portscanning hackers from accessing my computer effective making my computer invisible to the internet. Another good thing.
Normally I wouldn't encourage newbies to get involved in firewalls and the like -- too complicated with uncertain results. However, with ZoneAlarm I'd say go ahead give it a go. The download is free for personal or non-profit use. And with the new tests ZoneAlarm has been shown to be king of the mountain when it comes to keeping track of who and what your computer talks to.
When an application on your computer tries to access the Internet, ZoneAlarm makes sure it
has your permission first. This ensures that a rogue program will
not sneak your important data out onto the Internet. Here you can see a sample window. ZoneAlarm is asking
permission for this program to access the internet. You'll notice you can give permission on a one time
only basis or on a permanent basis.