A credit card is a small plastic card issued by a bank, business, or other organization, allowing the holder to make purchases or withdrawals on credit, which is a form of unsecured loan from the issuer. There is a maximum amount of credit that a card can provide, called a credit limit, which should not be surpassed. Exceeding the limit may require the credit card holder to pay a credit limit fee. At the end of the month, the credit card holder can choose to repay the entire amount or leave an unpaid balance that is subject to interest until it is paid off. Note that credit card interest rates tend to be relatively high compared to other common loans such as mortgages, car loans, or student loans, and as such, the balance should ideally be paid off monthly to avoid paying large amounts of interest. Examples of credit card issuers include banks, credit unions, or retailers, and examples of credit card networks include Visa or MasterCard.