Debt

A debt generally refers to money owed by one party, the borrower or debtor, to a second party, the lender or creditor. The borrower or debtor may be a sovereign state or country, local government, company, or an individual. The lender or creditor may be a bank, credit card company, payday loan provider, or an individual. Debt is generally subject to contractual terms regarding the amount and timing of repayments of principal and interest. The term can also be used metaphorically to cover moral obligations and other interactions not based on economic value. For example, in Western cultures, a person who has been helped by a second person is sometimes said to owe a "debt of gratitude" to the second person.

Interest is the fee charged by the creditor to the debtor. Interest is generally calculated as a percentage of the principal sum per year, which percentage is known as an interest rate, and is generally paid periodically at intervals, such as monthly or semi-annually.

Many conventions on how interest is calculated exist – see day count convention for some – while a standard convention is the annual percentage rate (APR), widely used and required by regulation in the United States and United Kingdom, though there are different forms of APR.

Interest rates may be fixed or floating. In floating-rate structures, the rate of interest that the borrower pays during each time period is tied to a benchmark such as LIBOR or, in the case of inflation-indexed bonds, inflation.

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