Use the right firewall for your version of Windows

A firewall helps protect your computer from hackers who might try to delete information, crash your computer, or even steal your passwords or credit card numbers. Depending on which operating system you have on your computer, you might already have a firewall and it might already be turned on for you.
A firewall is included in most Windows operating systems. To turn on or check your firewall settings, click the link that corresponds to the operating system you use.
For more information, see Beyond the Basics: Firewalls.