Calling cards are those cards you get handed to you on the street sometimes, or see advertised in corner shops. They’re a cheap way to call internationally – much cheaper than a normal landline phone – and they’re getting more and more popular as more people choose to live and work in foreign countries and make friends internationally.

So how do calling cards work? There are two main kinds of cards: free and paid-for. Free cards have a premium rate phone number on that you then call and enter your card number and PIN number. The premium rate phone call pays for a certain number of minutes for you to the country of your choice. Paid-for cards work similarly with the card number and the PIN, except that you buy them in a shop instead of paying with a premium rate call.

The reason your calls can be so much cheaper than usual when you use a calling card is that they are no longer being routed through the normal phone network. Instead, calling card companies are free to construct their own international telephone networks, often using advances in technology to their advantage.

Most modern calling cards actually route calls over the Internet, which means that an international call in fact becomes only a local call at each end, with the Internet acting as a ‘bridge’ between the two phone networks. This means that the calling card companies can make a lot of money for very little work, while also providing a much cheaper service than usual to the customer.

If you want to cut out the middleman, though, you might consider using a voice-over-IP service on your computer, such as Skype. This allows you to make Conference calls for free over the Internet, and at local rate to landline phones all over the world. While you have to have a computer and Internet access and use a headset instead of a phone, the calls are a lot cheaper than even the cheapest calling card.