The mortgage term is the period used to calculate the mortgage payment, which varies on FRMs from 10 years to 40 years. See Selecting the Term on a Mortgage. Virtually all ARMs have terms of 30 years.

Monthly Payment Calculator: Fixed Rate Mortgages.
For borrowers who want to explore how the term together with the interest rate affect the mortgage payment.

Mortgage Term Calculator: Investing in a Shorter Term.
For borrowers with sufficient income to afford the higher monthly payment on a shorter term FRM who may want to know whether the higher payment is a good investment.

Mortgage Term Calculator: Investing the Cash Flow Savings on a Longer-Term Mortgage
For borrowers with sufficient income to afford the higher monthly payment on a shorter term FRM who want to know the rate of return they must earn on the cash flow savings from a longer term to make the longer term pay.