CVV is the credit card security code that people often say. The security code is printed on the card face of the credit card, usually the last three digits of the signature column on the back of the credit card. Some CVV codes are four digits, and different types of credit card security codes are printed in different locations. This CVV is equivalent to a credit card ID card. Credit card holders can use their credit card security codes for consumer transactions. When people make transactions through the Internet or telephone, they can use the credit card number, expiration date and security code to make payment transactions.

1, CVV password verification means that commercial banks add the verification code of self-defined algorithm to the bank card number coding rules and magnetic stripe data format they use, and the related bank cards are also called CVN bank cards. CVV information is stored in the track of magnetic stripe bank card. According to the information such as card number, track main account number and logo code of issuing bank, it is encrypted by special encryption algorithm defined by each bank, and every step is encrypted by CVKA technology to get verification code. Because the encryption algorithms of different banks are different, some fake cards illegally made by using the obtained bank card information can be identified and cannot be used when the issuing bank decrypts them.

2. How to protect the credit card security code? After all, the security code has its unique function, which is generally needed when activating credit cards, binding credit card payment and online consumption, and printed on cards for the convenience of cardholders. So it's best not to erase it. You can put a small piece of paper on it to cover it so as not to be known by you. In addition, when spending outside, don't let the credit card leave your own realization, try to hold the card in person and don't give it to strangers to avoid the risk of information being stolen.

3. After understanding the meaning of CVV, what are the precautions when using CVV?

(1) Don't write credit card information on the computer;

(2) Don't give others a credit card easily;

(3) After the credit card is lost, immediately call the bank customer service phone to report the loss;

(4) Credit card is a payment and settlement tool based on credit system. So please take the monthly statement seriously and confirm the consumption. If you find some abnormal consumption, you can refuse to pay if you provide evidence.

(5) If you think it is dangerous to inform the credit card number, expiration date and other information, it is recommended that you pay through online payment, because the credit card information will be input into the bank's online banking, and all information will not be saved in the hands of merchants.