One answer to such a problem is the use of a firewall. Unlike its name suggests, a firewall does not surround your computer with flames that threaten to touch anybody getting close, however in principle this idea is not too far from the truth! In this article I will be looking at what a firewall is and what you can expect to get from using one.

So what is a firewall?

A firewall is a term used to describe a device or application that will control and restrict data transfers between a computer system and internet connection. The purpose of having a firewall in place is to not only prevent unauthorised or maliscious data entering your system via your internet connnection, but to also prevent sensitive information from leaving you system

There are basically two types of firewalls, these are hardware firewalls and software firewalls. A hardware firewall is a physical device that is installed between the modem and computer or, in the case of network of computers, it may be linked/incorporated into a broadband router being used to share the internet connection can also act as a firewall device. A software firewall however is a software application that is installed onto the computer system that you wish to protect and this is usually the computer with the modem attached to it.

The difference is demonstrated in the diagram below, as you can see a hardware firewall normally acts as a barrier between a network of computers and an internet connection (although it can be used with a standalone computer) whereas a software firewall is generally installed on a computer system connection to the internet.