the system of credit cards is a type of retail transaction settlement and credit system, named after the small plastic card issued to users of the system. the main different of credit cards from a dedit cards in which, during every transaction, the money from the users's account is removed. But in case of credit card, issuer lends money to the consumer (or the user). It is also different from a charge card, that require 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.
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