The security code of UnionPay standard card organized by UnionPay, debit card at the bottom of the card and credit card at the back of the card are all three digits, which can identify whether there is a bank card transaction.

The main purpose and safety reminder of credit card security code;

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. Therefore, everyone must take good care of their credit cards, and don't let them leave their sight when spending, so as to avoid others remembering your credit card account number and security code.