Visa's
Card Verification Value (CVV) (which most cards now have
and MasterCard's Card Validation Code (CVC) were
introduced several years ago as an additional security
measure in the fight against fraud. The 3-digit number
is only printed on the back of your card. It is not
printed on receipts, and is not stored anywhere, so the
only way to know the correct number is to have
possession of the card.