Compound interest can help turbocharge your savings and investments, or it can quickly lead to an unruly balance, keeping you stuck in a cycle of debt. Its magic can help you earn more — or owe more.

Interest is the amount of money you must pay to borrow money in addition to the loan's principal. It's also the amount you are paid over time when you deposit money in a savings account or certificate ...

Compound interest is interest that's calculated on both the initial principal of a deposit or loan and on all accumulated interest. It's a tremendous advantage for savers and investors but not so much ...