Bank card is a credit payment tool issued by commercial banks, postal savings institutions and other financial institutions to the society, which has all or part of the functions of consumer credit, transfer settlement and cash deposit and withdrawal. Bank cards include credit cards and debit cards. Because all kinds of bank cards are made of plastic, they are also used for deposit and withdrawal and transfer payment, so they are also called "plastic money". The size of bank cards is generally 85.60× 53.98 mm (3.370× 2.125 inch), and there are also mini cards and irregular shapes that are 43% smaller than ordinary cards.