A letter of intent is needed when you want to apply for something. You need them to know that you are interesting and formally want to apply for it. The letter of intent is the way you do it. You begin the letter by listing their address. You then state the program or thing you wish to apply for. You then list all of your relevant personal information such as your name, address, phone number, email address and anything else which is pertinent to your application. There may also be some sort of application form you need to fill out and complete which you submit along with the letter. A letter of intent is like a contract but it isn't binding. Rather the point of the letter of intent to clarify things and make sure both parties are on the same page. It also provides a useful backup if things go sour and collapse. Those commonly using letters of intents are people applying to colleges. The letter of intent indicates that the student wants to attend that college. Every school or college has its own requirements as far as letters of intent go so its best to check these out before writing yours.