"CVV", is short for Card Verification Value. It is the most basic security check websites do to make sure the Credit Card (CC) is valid or "correct".
On most cards, MasterCard and Visa and Discover the CVV is printed on the back of the card.
It is a 3-digit value. Like shown:
However, on American Express cards the CVV is printed on the front of the card.
It is a 4-digit value. Like shown:
I hope that clears any questions you might have had and don't be afraid to ask questions like these because if you never ask, then you will never know.
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