Interest (finance) — cost of borrowing and reward for lending
Interest is the payment made for use of money over time. This article explains definitions, types (simple, compound, nominal, real), key components, historical context, common uses, and important distinctions.
Definition
Interest is the compensation paid by a borrower to a lender for the use of money over time. It is usually expressed as a rate — a percentage of the outstanding principal — and reflects the time value of money, inflation expectations, and credit risk. In everyday language interest can refer both to the rate itself and to the dollar amount charged or earned.
For a concise description, interest is the cost of borrowing money or the payment received for lending it: see cost and borrowing money.
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Types and characteristics
Key components that determine interest include the principal (the original sum), the interest rate, the term (length of time), and the compounding frequency. Important distinctions:
- Simple interest: calculated only on the principal.
- Compound interest: calculated on principal plus accumulated interest; frequency (annual, monthly, daily) affects growth.
- Nominal vs real: nominal rates do not adjust for inflation; real rates subtract expected inflation to reflect purchasing-power change.
- APR vs APY: annual percentage rate commonly quotes borrowing cost without compounding; annual percentage yield (APY) reflects compound earnings.
These features determine how much a borrower pays or a lender earns and affect comparisons among loans, savings accounts, and investments.
History and development
Practices resembling interest date back to ancient civilizations where grain or coin lending occurred. Many cultures and religions historically restricted or condemned excessive interest (usury), which shaped early banking and legal frameworks. Over centuries, as commerce and finance evolved, formal banking, bond markets, and central banking institutions developed tools to set benchmark interest rates that influence economies.
In modern finance, interest rates are a central policy tool: central banks adjust policy rates to influence inflation, employment, and growth. Market interest rates also reflect creditworthiness, liquidity conditions, and term structure (short- vs long-term rates).
Uses, examples and notable distinctions
Interest appears in mortgages, personal loans, credit cards, government and corporate bonds, and savings accounts. Borrowers pay interest as part of repayment; savers receive interest as income. Distinctions to note include interest versus fees (fees are fixed charges unrelated to outstanding balance) and interest versus capital gains (interest is periodic income; capital gains come from asset price changes). Excessive interest charged beyond legal or ethical norms is often labeled usury and may be regulated.
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AlegsaOnline.com Interest (finance) — cost of borrowing and reward for lending Leandro Alegsa
URL: https://en.alegsaonline.com/art/47587