There are several types of mortgage loans, but the most commonly used are fixed-rate and adjustable-rate loans. Fixed-rate loans have the same interest rate for the entire duration of the loan. That means your monthly payment will be the same, even for long-term loans, such as 30-year fixed-rate mortgages. Two benefits to this loan type are stability, and being able to calculate your total interest up front. Adjustable-rate mortgages (ARMs) have interest rates that can change over time. Typically they start out at a lower interest rate than a fixed-rate loan, and hold that rate for a set number of years, before changing interest rates from year to year. For example, if you have a 5/1 ARM, you will have the same interest rate for the first 5 years, and then your interest rate will change from year to year. The main benefit of an adjustable-rate loan is starting off with a lower interest rate.