Skimming happens when someone copies the magnetic stripe on a credit or debit card by swiping it through a small card reader. This can happen in shops, restaurants or anywhere where you might pay with your card, and it results in your card details being used to make a counterfeit card.

Guard your card and never let it out of your sight when making a transaction, and don't carelessly discard receipts as they carry information about your card that a fraudster could use to buy things over the phone or internet. Check your receipts against your statements carefully, and if you don't recognise a purchase, contact your card issuer immediately.

Sign new cards as soon as they arrive and make sure you cut up your old card as soon as the new one becomes valid. Don't keep your chequebook with your cards, and look after all your personal possessions properly. And report lost or stolen cards to your card issuer immediately, a 24-hour emergency number is usually shown on your statement.

Mark Bowerman of the Association for Payment Clearing Services (APACS), which manages the main networks allowing UK banks and building societies to exchange payments on behalf of customers, explained what to do if your card is stolen: 'If someone else uses your card before you tell your card issuer it has been lost or stolen the most you will have to pay, in theory, is £50. The same applies if you warn them that someone else knows your PIN.

'In practice, the bank or building society will usually refund the full amount lost, but if you the cardholder were negligent, for example, by keeping your PIN with your card, you would have to meet all the losses. If your card is used fraudulently but you still have the card, as with skimming, you will not be liable to pay for any part of the losses.'