[ManD1]

My grandparents just bought a new computer. They know how to turn it on, compose an e-mail, surf the Internet, open documents and files, etc. However they are security illiterate. Their system doesn't have any firewall and I'm willing to install one. I know a lot of good firewalls, but all of them are paid and quite expensive. Grandparents don't want to spend few extra bucks on firewall. So what free firewall can I install? And overall is there any free firewall at all?

[Jim]

Why don't you try ZoneAlarm? This freeware product is one of the best firewalls I know. A lot of security experts recommend using it. You can download ZoneAlarm from here.

[clix]

There is another free one - Kerio Personal Firewall 2.15. Unfortunately, all further releases are paid. There is also an open-soruce clone of KPF 2.15 called Ghost Personal Firewall. You can download it here.

[Jim]

I also found this list of free firewalls. You may find it useful.