Adjustable Rate Mortgages (ARMs) are home loans that have interest rates that can fluctuate over the life of the loan. This means the monthly payment can vary throughout the life of the loan.

ARMs are expressed using two numbers, such as 5/1 or 7/1. The first number indicates the number of years that the initial interest rate is fixed, while the second number indicates the number of years that the rate can adjust after the initial fixed rate period.

For example, with a 5/1 ARM, the initial interest rate will be fixed for the first 5 years of the loan. After these 5 years, the rate can adjust every year.