A VoIP system works by taking your analogue voice signals, converting them into digital signals, then sending them as data over your broadband line.

It’s a very useful way of making calls – for a start, once it’s set up it’s a lot cheaper than using normal phone lines. It means that, depending on your setup, you may not have to pay for your phone calls based on distance, which country you’re calling, or how much time you spend chatting.