Debit cards work over the same worldwide networks (MasterCard, Visa, etc.) used to process credit card payments. You can use your card two ways:

 

    • With a personal identification number (PIN) to withdraw cash from an ATM or to request "cash back” at stores when making a purchase
    • With your signature or PIN to pay for goods, meals, gas and services.                               

While debit cards look similar to credit cards, they work differently. You can't use them to charge a purchase and pay it back over time, as you can with a credit card. For your debit card to work, you must have enough money in your checking account to cover transactions unless you have overdraft protection.