Calculate compound interest with different compounding frequencies.
Compound interest is interest calculated on the initial principal and also on the accumulated interest from previous periods. It makes your money grow faster over time.
More frequent compounding (daily > monthly > quarterly > yearly) results in slightly higher returns because interest earns interest more often.
The Rule of 72 is a quick way to estimate how long it takes for an investment to double. Divide 72 by the annual interest rate to get approximate years.