Hello, the last three digits of the signature column on the back of the credit card are CVV codes, which are the only verification codes randomly generated when making credit cards, and are also equivalent to the ID number of each credit card. It is an important verification code in the case of non-face-to-face payment (such as online shopping and telephone orders).

This verification code is only known to the cardholder. Do not disclose this code to others. The function of this security code is as follows:

(1) credit card security code, which is the security code of credit card in network or telephone transaction;

② It is usually a 3-digit or 4-digit number printed on a credit card, and the printing position of different types of cards will be different;

It is usually used to prove that the payer has a credit card at the time of transaction to prevent credit card fraud.

: 1. What is a credit card?

Credit card, also known as credit card, is a credit certificate issued by commercial banks or credit card companies to eligible consumers. The form is a card with name, expiration date, number and cardholder's name printed on the front, and magnetic stripe and signature strip printed on the back. Consumers with credit cards can shop or spend in specialized commercial service departments, and then the bank will settle accounts with merchants and cardholders. Cardholders can overdraw within a certain amount.

The credit card stipulated in the relevant laws of China (Interpretation of the NPC Standing Committee on the Provisions on Credit Cards in the Criminal Law of People's Republic of China (PRC)) refers to the electronic payment card issued by commercial banks or other financial institutions. It has all or part of the functions of consumption payment, credit loan, transfer settlement, cash deposit and withdrawal, etc. 20 17 12 1, the standard of English translation and writing in the field of public service was formally implemented, and the name of a credit card with English as the credit card standard was designated as a credit card.

Credit card consumption is a non-cash transaction payment method. There is no need to pay cash when spending, and the repayment will be made on the same day.

Credit cards are divided into credit cards and quasi-credit cards. Credit card refers to a credit card in which the cardholder has a certain credit limit and can spend first and then repay; Quasi-credit card refers to a quasi-credit card in which the cardholder deposits a certain amount of reserve fund according to the regulations, and when the balance of the reserve fund account is insufficient to pay, it can be overdrawn within the prescribed credit limit. Credit cards generally refer only to debit cards.