Firewalls are a great way to protect your computer from viruses and hackers. There are different levels of security that can be set, depending whether you are on a private network or the Internet. Typically you can allow more access for a small private computer than when you are connected to the Internet.

Firewalls used for Internet connections should be quite strict and allow minimum access. This is not to say that your online experience will be diminished. You simply want to restrict traffic not only leaving your computer but coming in as well. An Internet firewall should also close ports not being used. Luckily, most firewalls are very easy to configure and you can get yours set up with just a few clicks.

For a personal firewall to work there must be two components in use. One component inspects any data that may arrive and determine if it can be allowed through. The other component uses a policy to determine whether or not certain programs may access the Internet.

The first component is known as the packet filter. A packet is essentially data and the firewall determines if the packet is allowed through based on the policy set. If the packet does not meet the firewall policy it is simply dropped and never makes it to your computer. The second component is known as the application filter. The application filter allows programs to send or receive data through designated ports. The standard port number for the Internet is 80, and so most applications using the Internet will use that specific port.

Since other ports can be used by certain modules of some programs, it is still possible that your computer may become infected by a virus. If your anti-virus software doesnít catch one of these infected modules your entire computer is at risk. Because of this you shouldnít rely solely on your firewall for protection. Always have up to date anti-virus software and take care when engaging in file sharing practices on the Internet.