Credit cards are issued to cardholders by banks or credit card companies according to the credit and financial resources of users. Cardholders don't need to pay cash when using credit cards, they will make repayment on the bill date. Credit card is generally a special carrier plastic card with consumer credit, which is 85.60mm long, 53.98mm wide and 1mm thick. It is issued by banks to individuals and units, so that they can shop, spend and deposit and withdraw cash from banks. The form is a card with the name, expiration date, number and cardholder's name printed on the front, and a magnetic stripe and signature on the back.