Ghostwriter影子写手

Reader question:
Please explain this sentence, particularly ghost-wrote: She was listed as a co-author of the book, which means that she likely ghost-wrote the book.
My comments:
We are talking about her as a ghost writer here.
Ghost writer? Yes, writers who write a book or something for another person, usually a celebrity, for an amount of money in exchange for, in our case, being listed as a co-author even though she alone wrote the book or, in other cases, giving up the by-line altogether.
By-line is the line under the title of a book that states this book is written "By So-and-so".
In memoirs and autobiographies, this so-and-so is usually the hero himself or herself. For example, if someone ghost-writes a memoir for Donald Trump, the by-line will be Trump instead of the person who actually writes the book.
In the case of Trump, it"s kind of easy to understand why he would like to have someone write his personal history for him. If Trump writes his own book, rest assured it"ll be full of adjectives such as "big", "tremendous" and "incredible". In other words, Trump doesn"t have much of a vocabulary and isn"t known for having a way with words, so therefore it"s only logical that he will want someone to ghost-write on his behalf.