Highest Rated: Free Zone Alarm Firewall, Comodo Personal Firewall
A firewall prevents unsolicited communication to and from your computer. Sometimes a virus, spyware, worm, or a trojan (a virus that allows other people to control your computer) might automatically install on your Windows XP or Vista computer. A firewall will detect these malicious programs installation and prevent them from communicating to the hacker who might want to control your PC. Free Zone Alarm is probably the easiest most established firewall software to use. Another great firewall is Comodo Free personal firewall. The company is fairly new in the firewall software scene. However, the software has won PC Magazine’s editor choice. I have seen the software recommended all over the web. I would definitely also give it a look.