CVV2 is a credit card security code, which is a set of 3 or 4 digits on the credit card. Its generation method is that the bank extracts the account number, validity period and service code of the card, arranges them and then calculates them through a series of complicated algorithms. After this set of numbers is generated, only the issuing bank and the holder of the bank card know what this number is.
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The credit card security code is equivalent to the credit card ID card, and we can use this code for consumer transactions. You don't need a password to shop on overseas websites. As long as the buyer provides the account number and security code, the transaction can be completed. In China, there are also merchants signing contracts with banks, but you don't need a credit card password, you only need a security code to complete the telephone transfer.
The credit card security code, like the CVV code, is the card verification value obtained by the same algorithm, except that when the card is generated, the CVV code is written into the magnetic stripe and the credit card security code is written on the card.
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