A Letter of Invitation is one of the documents that first-time-candidates have problems learning how to generate, the reason why it wanted, and best places to submit it. Actually, every little thing related to a Letter of Invitation is pretty simple and easy. There is no need to be a professional of some sort of subject so that you can write down a Letter of Invitation, or even to obtain one.
When composing an invitation letter, the biggest thing the author has to remember, is usually that the letter need to contain some vital facts, of the number as well as the visitor.