A smart card, chip card, or integrated circuit card (ICC), is any pocket-sized card with embedded integrated circuits which can process data. This implies that it can receive input which is processed — by way of the ICC applications — and delivered as an output. There are two broad categories of ICCs. Memory cards contain only non-volatile memory storage components, and perhaps some specific security logic. Microprocessor cards contain volatile memory and microprocessor components. The card is made of plastic, generally PVC, but sometimes ABS. The card may embed a hologram to avoid counterfeiting. Using smart cards is also a form of strong security authentication for single sign-on within large companies and organizations.
A debit card (also known as a bank card or check card) is a plastic card that provides an alternative payment method to cash when making purchases. Functionally, it can be called an electronic cheque, as the funds are withdrawn directly from either the bank account, or from the remaining balance on the card. In some cases, the cards are designed exclusively for use on the Internet, and so there is no physical card.
The use of debit cards has become widespread in many countries and has overtaken the cheque, and in some instances cash transactions by volume. Like credit cards, debit cards are used widely for telephone and Internet purchases, and unlike credit cards the funds are transferred from the bearer's bank account instead of having the bearer to pay back on a later date.
Debit cards can also allow for instant withdrawal of cash, acting as the ATM card for withdrawing cash and as a cheque guarantee card. Merchants can also offer "cashback"/"cashout" facilities to customers, where a customer can withdraw cash along with their purchase.
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