Firewalls are hardware devices or software programs, or combinations of both, used to filter and stop information sent and received via the Internet. They are used as a means of keeping networks secure.
Although there is a law of diminishing returns (the more secure the firewall makes the network, the harder it is for normal users to access the Internet and use the machine normally), Tabard IT recommends you always install and properly configure a firewall before connecting to the internet.
For home users, there are free firewalls available. Windows XP Service Pack 2 comes with a firewall built in. ZoneAlarm is a good, free firewall for all versions of Windows. Also, if you use a broadband router, this acts as a firewall.
For business users, there are hardware and software products available, ranging from around £50 (ie a router) right up to several thousands of pounds (for example Watchguard Firebox firewalls), depending upon how important security is for you.
If in doubt, please contact us.