What Is APR?
APR, or annual percentage rate, is the yearly cost of borrowing money, expressed as a percentage of the balance you carry.
APR includes the interest rate on a loan or credit card, plus certain fees, rolled into one yearly percentage. On a credit card, most of that APR comes from interest. On a mortgage, APR can include origination fees and points, which is why APR is usually higher than the quoted interest rate.
APR is not what you pay each month. It is an annualized rate. To find your actual monthly cost, divide by 12: a 24% APR charges roughly 2% interest per month on your balance.
APR only applies to money you carry forward. Pay your credit card balance in full each month and the APR never touches you, because there is no balance left to charge interest on.