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PC Security

Security scanners, tools, and safety guidelines for your PC, laptop, or mobile device.

What is a firewall?

What is a firewall?

A firewall is a software program or piece of hardware that helps screen out hackers, viruses, and worms that try to reach your computer over the Internet.

Firewall Diagram

  • If you use a computer at home, the most effective and important first step you can take to help protect your computer is to turn on a firewall.

  • Windows 7, Windows Vista, and Windows XP SP2 or higher have a firewall built-in and turned on by default.

  • If you have more than one computer connected in the home, or if you have a small-office network, it is important to protect every computer. You should have a hardware firewall (such as a router) to protect your network, but you should also use a software firewall on each computer to help prevent the spread of a virus in your network if one of the computers becomes infected.

(If your computer is part of a business, school, or other organizational network, you should follow the policy established by the network administrator.)