‘A synopsis is a brief summary that gives readers an idea of what a composition is about’, says LiteraryTerms.net. It provides an overview of the storyline, main points and other defining factors. I like to see a synopsis for all nonfiction works that includes the intended readers’ interest base and the book type (self-help advice, tips, how to manual, part-memoir, etc).
Authors often need to provide a lengthy synopsis when proposing a book or other work to potential publishers or editors, particularly in the traditional publishing path. Editors also use the synopsis to assess what type of work this is, what kind of reader, what gap in the marketplace it might fit into, and what are the book’s aims and overriding voice.