A credit card is different from a charge card: a charge card requires the balance to be paid in full each month. In contrast, credit cards allow the consumers a continuing balance of debt, subject to interest being charged. A credit card also differs from a cash card, which can be used like currency by the owner of the card. Most credit cards are issued by banks or credit unions, and are the shape and size specified by the ISO/IEC 7810 standard as ID-1. This is defined as 85.60 × 53.98 mm (3.370 × 2.125 in) (33/8 × 21/8 in) in size.
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