A CVV number is a unique identifier for a credit card. It is used to uniquely identify the cardholder and helps protect the card from being stolen. CVV numbers are typically generated on a personal computer or phone when you first create an account with a credit card company.

It’s an Extra Layer of Protection

The CVV is a three- or four-digit security code on the back or front of your credit card that helps protect you from credit card fraud.

For Mastercard, Visa, and Discover credit cards, the CVV code is three digits, and it’s located on the back of the card near the signature line. On American Express cards, the CVV code is four digits long, and you’ll find it on the front of the card.

Under industry rules laid out by the PCI Security Standards Council, retailers can’t store CVV with your credit card information in a database. That means that if your payment information leaks or gets hacked, you’ll have an extra layer of protection that only exists on the physical card itself.

The use of CVV in verifying purchases is optional, so some vendors can still process payment without it. That means those vendors can also store credit card information without the CVV and process payment anyway. But when retailers ask for it, it’s one more layer of security against online database hacks.

RELATED: How to Stop Identity Thieves from Opening Accounts in Your Name

Other Names for CVV Codes

Credit card security codes go by a number of different names based on various vendors. Here are a few common ones and what they mean.

CVV: Card Verification Value, used with Visa cards. CVV2: Card Verification Value 2, used with Visa cards. CVC: Card Validation Code, used with Mastercard. CVC2: Card Validation Code 2, used with Mastercard. CID: Card Identification Code, used with some American Express and Discover cards. CVD: Card Verification Data, used with some Discover cards. CSC: Card Security Code, used with American Express cards. SPC: Signature Panel Code, a generic term for the security code.

Believe it or not, those aren’t the only three-letter acronyms out there, but we’d covered the most major ones. Whatever the name, CVV codes alll serve the same purpose: they help you shop safer online. Happy shopping!

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