You should write your name on the credit card and have your signature recognized when making purchases. For credit cards without passwords, it is the only identifier. So it's best to sign them all, so that you have an extra layer of security if they are stolen or picked up.

Specific reasons

There are 2 security measures on the back of the credit card. The first is a CVV code consisting of 3 digits, and the second is a handwritten signature. Generally speaking, when you use a credit card to pay online, you need to fill in the CVV code; when using a credit card for offline purchases, merchants often need to ask for a signature on the back of the credit card;

The reason why a signature is required is also for security reasons. ; Because shopping through offline channels requires a signature on the bill details. The formal process is that the salesperson will compare the signature on the credit card with the signature on the bill. If the handwriting is obviously different, it may indicate that the credit card is not my credit card. .