The Card Identification Number
A four digit, non-embossed number printed above your account number on the face of your card. This number is recorded as an additional security precaution.
CID, CVV2: A Three-Digit Number
An important new security feature for card-not-present transactions that appears on the back of most cards. This feature provides a cryptographic check of the information embossed on the card.
The three-digit number is printed on the signature panel on the back of the cards immediately following the card’s account number.