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.

This is an excerpt from Dollar Scholar, the Money newsletter where managing editor Julia Glum teaches you the modern money ...

If you have a savings account, you might want to know how much you’ll earn in interest for parking your cash there. Fortunately, calculating interest on a savings account is not as tough as you might ...