Credit Card

What it is:

A credit card is a plastic card issued by a financial institution that allows its user to borrow pre-approved funds at the point of sale in order to complete a purchase.

How it works/Example:

Credit cards have a maximum amount -- or credit limit -- the user can borrow during a given period. The credit limit is pre-determined by the card issuer based on the cardholder's credit rating and credit history. 

When an individual uses a credit card to make a purchase, he or she is authorizing the credit card issuer to pay the merchant on their behalf. Merchants are required by law to verify that the individual using the card is its rightful owner by obtaining proper identification via a Personal Identification Number (PIN), and/or a driver's license or state-issued ID card. 

Merchants generally prefer payment by credit card because they are immediately paid by the card issuer – despite the fee the merchant must pay to the card processing company for each transaction.

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Credit card issuers require the cardholder to pay his or her balance in full, usually on a monthly basis. If the user does not pay the balance in full, the issuer adds interest to the balance, and this interest compounds for as long as the balance is outstanding. 

As with credit limits, the cardholder's credit rating and credit history can influence the interest rate on the card. In some cases, the issuer can raise the interest rate. There is no federal limit on the interest rates credit card issuers can charge, although many states impose different caps. Many card issuers offer "teaser rates" that start out very low and increase over time. 

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Issuers use several methods to calculate interest, and it is important for the cardholder to read and understand the issuer's disclosure statement in order to avoid unpleasant surprises. Many credit cards also charge an annual fee, late payment fees, fees for going over the credit limit, cash-advance fees and foreign-currency conversion fees.

Why it Matters:

Credit card interest rates are higher than personal loans or lines of credit. Many credit cardholders underestimate the time and money it takes to pay off outstanding balances -- especially when interest rates are high and minimum payments are low. 

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It is important that cardholders not only use credit cards in moderation, but also take preventative action against identity thieves in order to protect their privacy and identity.

Credit cards allow cardholders to avoid carrying cash, earn frequent-flier miles, or accumulate other "rewards" that can be used almost anywhere around the world. With many credit card types, the cardholder can also get cash advances through ATMs. 

Best execution refers to the imperative that a broker, market maker, or other agent acting on behalf of an investor is obligated to execute the investor's order in a way that is most advantageous to the investor rather than the agent.