In the U.S., it's easy accumulate many different cards that you store in your wallet (purse). They are all used for various different purposes. Many wallets have transparent storage pockets. Most of the cards are made of plastic or laminated.

Credit cards allow you to make purchases or get cash advances, which you have to pay off later. 
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Debit cards are similar to credit cards, but the money is immediately deducted from your checking account.
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ATM cards allow you to withdraw money from your bank account from an Automated Teller Machine. Many times, an ATM card and a debit card are combined into one card.
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Many gas stations, grocery stores, pharmacies, etc., issue a card that will give you discounts at the time of purchase. These cards are primarily designed for customer loyalty and give customers incentives to visit a particular store rather than their competitors.

When you go to the doctor, hospital, or pharmacy, you will be asked for proof of insurance. You may have one or several cards to do this with, depending on your insurance types. Typically, you will have a health insurance card, a pharmacy card, and a dental insurance card. Some cards may combine several items into one, such as health + pharmacy. These cards will typically have your name, group number, ID number, effective date, and the claims filing information of the insurance company, such as name, address, and phone number.

Even though technically not a card, it is of the same size as other cards that go in your wallet. In addition to it's declaration of your ability to drive a car legally, it is the single most widely used photo ID document.
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For no charge, you can become a member of the local library, the city, town, or county you live in. You must show proof of your residency, such as a driver's license, to become a member. The library will issue a membership card, which allows you to check out books and use library facility.

Many prepaid calling cards are available to make long distance and international calls.
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There are several wholesale clubs around the United States that let you purchase items in large quantities, which will save you money. They charge an annual membership fee to let you enter into their store. They give each member a membership card. Prominent wholesale clubs are Costco, Sam's Club, and BJ'S Wholesale Club.

Many video rental libraries issue cards, as well. It will contain details about the issuer and typically your name and account number.

Many other organizations, such as health clubs, may issue membership cards.