let me give you an answer. At present, there are basically two trading methods for credit cards issued by domestic banks, one is based on signature, and the other is based on signature and password, which means no password is needed. After consumption, the merchant is responsible for confirming whether your signature on the POS slip matches the one on the back of the card. This method is the most widely used in foreign countries. If you use the consumption mode of signature only, and the merchant fails to carefully check the signature as required when the credit card is stolen, you can investigate the responsibility of the merchant according to law. 2 is that many banks now have the function of paying for lost cards, including 24-hour and 48-hour. It means that you are not responsible for the money stolen within 24 hours or 48 hours before you report the loss. In fact, this is the highest requirement for businesses, and they have the greatest responsibility. But now many businesses, especially individual stores and supermarkets, basically don't read your signature. If you have a password, you will pass it. If you don't have a password, you will pass it. Anyway, they just pay attention to the money finally coming to their account, without considering the responsibility they have to bear, but it is not good for them to be irresponsible. If they consume by signature, they can only lose money if they don't verify the signature. (Personally, I think this and many banks and UnionPay are installing POS machines, which is caused by insufficient training for cashier, or no training at all.) But now many 4.5-star hotels and many foreign businesses attach great importance to this, because there are many foreign customers, so if there is no signature on the back of the card in these places, it will not be swiped for you. In China, it is still recommended that you use password and signature. Also, sign your name on the back, no matter which way you spend it, it's good.