What is the Security code or Card Verification Code (CVC) ?
The card security code is a three-digit number (four-digit on American Express) printed on your credit card. This number is not embossed on the card and hence not printed on receipts - making it difficult for anyone other than the genuine cardholder, to know it and to use it.

You will find this three-digit security code of Mastercard and Visa credit card printed at the top of the signature strip on the reverse of the card.

You will find this four-digit number security code of American Express credit card printed on the front of the card, above the account number