Without affecting the use of bank cards, it is better to delete them directly or clean them with alcohol, and clean and fill them. The signature on the back of the bank card should be signed by the cardholder himself. Usage: 1, which can prevent others from impersonating you to withdraw money or spend money at the counter. When withdrawing money or spending money at the counter, the waiter will check whether the signature is consistent with the signature on the card. 2. It can prevent your card from being swallowed when you withdraw money from ATM, and you can recognize it as your own card when you go to the bank to get it. It will be more convenient to sign your name on the back of the card.