How to Choose a Firewall

Computer firewalls: Everything you need to know

Everyone says you should use a firewall to help protect your computer when you go online. But what exactly is a firewall, and how does it defend your PC? Get answers to these and other questions in our:

• frequently asked questions page on firewalls.
• Learn what a firewall is
• See how to tell if your computer already has one.
• And if you need a firewall, get the pros and cons of each type so you can pick the right one for you.

Microsoft Security Newsletter.