Firewall Security Guide

How do I choose a firewall?
A firewall works by examining information coming from and going to the Internet. It identifies and ignores information that comes from a dangerous location or seems suspicious. If you set up your firewall properly, hackers searching for vulnerable computers can't detect your computer.
There are three basic types of firewalls available today. The first step in choosing a firewall is to determine which one is best for you. Your options include:
Software firewalls
Hardware routers
Wireless routers
To get started, answer these questions and record your answers:
1.How many computers will be using the firewall?
2.What operating system are you using? (This might be a version of Microsoft Windows®, Apple Macintosh, or Linux.)
3.That's it. You are now ready to start thinking about what type of firewall you would like to use. There are several options, each with its own pros and cons.
Understanding Windows Firewall
Windows Firewall, previously known as Internet Connection Firewall or ICF, is a protective boundary that monitors and restricts information that travels between your computer and a network or the Internet. This provides a line of defense against someone who might try to access your computer from outside the Windows Firewall without your permission

How Windows Firewall Works
When someone on the Internet or on a network tries to connect to your computer, we call that attempt an "unsolicited request." When your computer gets an unsolicited request, Windows Firewall blocks the connection. If you run a program such as an instant messaging program or a multiplayer network game that needs to receive information from the Internet or a network, the firewall asks if you want to block or unblock (allow) the connection

What Windows Firewall Does and Does Not Do
It does
It does not
Help block computer viruses and worms from reaching your computer.
Detect or disable computer viruses and worms if they are already on your computer. For that reason, you should also install antivirus software and keep it updated to help prevent viruses, worms, and other security threats from damaging your computer or using your computer to spread viruses to others. For more information, see
Ask for your permission to block or unblock certain connection requests.
Stop you from opening e-mail with dangerous attachments. Don't open e-mail attachments from senders that you don't know. Even if you know and trust the source of the e-mail you should still be cautious. If someone you know sends you an e-mail attachment, look at the subject line carefully before opening it. If the subject line is gibberish or does not make any sense to you, check with the sender before opening it.
Create a record (a security log), if you want one, that records successful and unsuccessful attempts to connect to your computer. This can be useful as a troubleshooting tool.
Block spam or unsolicited e-mail from appearing in your inbox. However, some e-mail programs can help you do this.