CSC (Card Security Code) has various names, depending on the processor. Visa calls it CVV2. MasterCard calls it CVC2, and American Express calls it CID. OnlineNIC uses the term CSC as a consistent name.

The CSC is printed on the back of most cards (usually in the signature field). All or part of the card number appears before the CSC (567 in the example). For American Express, the 4-digit number (1122 in the example) is printed on the front of the card, above and to the right of the embossed account number.