What is a Card Verification Value (2) (CVV2)?
VISA® credit and debit cards have a 3-digit code, called the “CVV2” (card verification value). 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. New North American MASTERCARD® and VISA® cards feature the "CVC2" in a separate panel to the right of the signature strip.  This has been done to prevent overwriting of the numbers by signing the card.
NOTE: This is the second code of the Card Security Code
Electronic Merchant Systems Payment Processing Glossary :
Defining key payment processing and merchant services industry terms to help business owners make better decisions.