Elvis Picardo is a regular contributor to Investopedia and has 25+ years of experience as a portfolio manager with diverse capital markets experience. Ali Hussain has a background that consists of a ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Daniel Rathburn is an editor at Investopedia ...

Interest rates are the costs of borrowing or returns on investments, expressed as a percentage of the initial amount, usually calculated annually. They are vital for loans, mortgages, and savings ...

Compound interest is a favorable method of compensating lenders and depositors wherein interest is periodically credited to the principal, and subsequent interest is paid on the increasing balance.

Once a principal balance earns interest, that interest becomes a part of the principal and continues to earn more interest—that is the magic of compounding.