The Secret is a self-help book written by Rhonda Byrne based on a documentary of the same name. It was released in 2006 and sold millions of copies worldwide.
The format of the book is similar to a book-length multi-level marketing Facebook post. It consists of one to three paragraphs of the author's prose followed by quotations that support the point being made. The book was originally written in 1910 by Wallace D. Waddles, a pioneer in the self-help genre.