A firewall is a piece of application software or a hardware device which provides protection to your computer system by screening out hackers, worms and viruses that try to infiltrate your computer system from the Internet with intents of causing damage to your computer system.

A firewall is different from an anti-spyware and antivirus although they all serve the purpose of protecting your computer system. Whether you have a small-office, home network or an enterprise network, activating a firewall software coupled with a firewall capable device will provide your network and all computers connected to it with the security that they need. Activating the firewall application on individual computers is necessary.