The 15 or 16-digit credit card number on the front or back of your card helps authenticate every purchase you make, whether you’re buying something in-person or online. Not only that ...

Credit cards add additional protection with an extra security number ... front of the card. Unlike Visa, Mastercard, and Discover, which have their three-digit security codes printed on the back ...

Credit card numbers are used to identify the card network ... your card will also have a three- or four-digit number either on the front or back. This number can be called the CVV, CVC, CVC2 ...