An automated teller machine (ATM), also known as a Cashpoint (which is a trademark of Lloyds TSB), cash machine or sometimes a hole in the wall in British English, is a computerised telecommunications device that provides the clients of a financial institution with access to financial transactions in a public space without the need for a cashier, human clerk or bank teller. ATMs are known by various other names including ATM machine, automated banking machine, and various regional variants derived from trademarks on ATM systems held by particular banks.

Invented by IBM, the first ATM was introduced in December 1972 at Barclays Bank in Enfield, UK. However, there is a plaque on Barclays Bank in Enfield Town, north London stating that the first ATM (in the world) was installed there on the 27th June 1967. On most modern ATMs, the customer is identified by inserting a plastic ATM card with a magnetic stripe or a plastic smart card with a chip, that contains a unique card number and some security information such as an expiration date or CVVC (CVV). Authentication is provided by the customer entering a personal identification number (PIN).

Using an ATM, customers can access their bank accounts in order to make cash withdrawals, credit card cash advances, and check their account balances as well as purchase prepaid cellphone credit. If the currency being withdrawn from the ATM is different from that which the bank account is denominated in (e.g.: Withdrawing Japanese Yen from a bank account containing US Dollars), the money will be converted at a wholesale exchange rate. Thus, ATMs often provide the best possible exchange rate for foreign travelers and are heavily used for this purpose as well.

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