With Apple Pay, instead of using your actual debit and credit card numbers when you add your card, a unique Device Account Number is assigned, encrypted and securely stored. And when you make a purchase, the Device Account Number alongside a transaction-specific dynamic security code is used to process your payment. Your actual debit and credit card numbers are never shared by Apple with merchants or transmitted with payment. In addition, paying with Apple Pay is private as the cashier never sees your name, card numbers or security code.