While Mortgage Prelude serves as a powerful mortgage calculator that computes such items as your monthly payment, amortization schedules, interest, etc., it is so much more than a common mortgage calculator. One of its most distinguishing features is that it uses the guidelines set forth by the Federal National Mortgage Association (a.k.a. Fannie Mae) in its computations. This is a very important concept because they are the same rules most lending institutions use when evaluating your request for a home loan.Via a very friendly interface, the program will prompt you for important input information such as your income and debt summary, and use the data you provide (along with the information you provide about the price of the home, interest rate, etc.) to actually compute if you have met the Fannie Mae Guidelines -- and it will conveniently do so before you ever have to meet with a loan officer. Mortgage Prelude will make the entire process of obtaining a loan as easy and quick as possible for you.We are confident that this is important because when you obtain a loan, there is a very high chance that your lender will want to have the option of selling your mortgage on what is called the secondary market for mortgages. (In fact, many lenders will sell your loan before you even make your first mortgage payment.) The two largest buyers of loans on the secondary market for mortgages are Fannie Mae and Freddie Mac and, thus, those two entities pretty much set the standards for home loans. What that means is that your lender will very likely want to make sure that the loan they grant you fits the industry standard Fannie Mae Guidelines so that they can sell your loan. Although there are many applicable guidelines, probably the most important are what are called the"Qualifying Ratios"(which are computed and displayed on Mortgage Prelude\'s main screen).