What is a CVV2 security code?
The Card Verification Value 2 (CVV2) security code, is part of a verification process developed by many credit card companies to reduce unauthorized use. It requires a card holder to enter the security code at checkout to verify that the card is on hand.

Where is my credit card's security code located?
For Most Credit Cards:
The security code is the three-digit code on the back of the card following your credit card number.