CVV/CVC code is a set of check codes printed on your credit card, usually 3 or 4 digits. It is a universal security code, which is used to verify the authenticity of credit cards and prevent them from being stolen or cheated. According to different types of cards, CVV codes are printed on the front or back of the cards. ?

The use of credit cards can be divided into "on-card transactions" and "off-line transactions". In the former, the cardholder swipes the card at POS terminals such as shopping malls and supermarkets, signs the authorization, and then completes the transaction.

Offline transactions are common when cardholders book hotels, air tickets or pay online. The merchant also provides the credit card account number and the last three codes through the POS system to complete the transaction.

At present, many domestic airlines and booking websites do not need to enter a password for credit card payment business, and only need to provide the website with information such as card number, expiration date and verification code to successfully pay. Therefore, credit card numbers and other related information are particularly important, and these information can be easily obtained by people you know.

At the same time, the reporter learned that at present, all booking websites cannot verify whether the booking person is the cardholder himself. In this way, it is possible to be used by the "willing people" around you and eat a dumb loss.