CREDIT CARD SECURITY CODES
The Credit Card Security Code is a security feature for credit or debit card transactions, providing increased protection against credit card fraud. As a security safeguard, you will be asked to provide the credit card security code during the setup of a quick checkout profile and for all other credit card transactions.
Credit Card Security Codes: Location on Your Card
MasterCard, Visa, and Discover credit and debit cards have a three-digit code, called the "CVC2" (card validation code), "CVV2" (card verification value), and "CID" (card identification number), respectively. It is not embossed like the card number, and is always the final group of numbers printed on the back signature panel of the card.
American Express cards have a four-digit code printed on the front side of the card above the number, referred to as the CID (or Unique Card Code). It is printed flat, not embossed like the card number.