Cash back credit cards are those that provide a percentage of the amount spent back to the consumer. Usually this percentage may vary from 2% to 5% depending on the credit card issuer. The cash back amount can be either credited to the card or can be offered as a check payment. The percentage of cash back may vary internally as well and may be different for grocery purchases compared to other purchases. Cash back credit cards are good for those people who spend a substantial amount on shopping and regularly use the card for gasoline or grocery purchases.