A credit card is a system of payment named after the small plastic card issued to users of the system. In the case of credit cards, the issuer lends money to the consumer (or the user) to be paid later to the merchant. It is different from a charge card (although this name is sometimes used to describe credit cards), which requires the balance to be paid in full each month. In contrast, a credit card allows the consumer to 'revolve' their balance, at the cost of having interest charged. Most credit cards are the same shape and size, as specified by the ISO 7810 standard. The most common credit card size, known as ID-1, is 85.60 × 53.98 mm.

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How Credit Cards Works