The credit card security code, namely cvv2 code, generally consists of 3 or 4 digits and is printed on the signature on the back of the credit card. It is mainly used for security authentication in the transaction process, such as card opening activation, online transaction, telephone transaction, etc. To confirm that the credit card is owned by the cardholder at the time of transaction.
Credit card security code is important information of the cardholder's account, so don't disclose it to others casually, so as to avoid the risk of the account.