The Card Verification Value (CVV), also referred to as CVV2 or CVC, is a security feature on debit cards designed to protect against fraud in card-not-present transactions, such as online purchases.
The CVV is usually a three- or four-digit number. On most cards, it is located on the back near the signature strip. For American Express cards, the CVV is a four-digit number found on the front. In the case of virtual cards, the CVV may also be displayed on the front.