You do this by using a personal identification number (PIN).

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The victim's card is apparently kept by the machine and the thief steps in and offers to help but asks the person to type in their Personal Identification Number (PIN).

BBC: Cash machine - generic

The industry hopes that the introduction in 2003 of chip cards and the personal identification number (Pin) payment system in the UK will lead to a significant reduction in most types of card fraud.

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If you have a "reasonable" expectation of victimization because your information was breached or you already have been victimized, ask the IRS for an identity protection personal identification number, or IP PIN.

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Proving more secure, chip-and-pin cards are embedded with microchips and require cardholders to input a personal identification number rather than signing receipts.

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