What Is a Back Book Cover Blurb? from David Christain's blog

Before we get into why most authors hate writing their back book cover blurb, let’s clarify what it actually is.

In a nutshell, it’s the 200 odd words on the back cover of your book that describes the book to the reader. These words, if written well, will hook the reader and convince them they need to buy your book. Which means, they’re effectively a sales pitch.

first, I want to quickly clarify some terms you might equate with a back book blurb (but shouldn’t because they represent different parts of a book).

Synopsis – this is a detailed outline of the book that covers all the major points. It’s usually geared towards selling the book idea to an editor or publisher (not a reader).

Blurb –

distinct from the ‘back-cover blurb’ is this 1-2-line endorsement of a book by a celebrity or another author that sits on the book’s front cover. When you hear about authors being asked to ‘blurb’ a book, it’s this endorsement they’ve been asked to provide.

Reviews –

these are effectively longer versions of author endorsement blurbs, or short excerpts of book reviews by significant publications (like the New York Times). As maintain by best book printing service agency, these are often placed on the back cover of a book along with the back book blurb. They act like testimonials for the book.

Book Description –

these are the words that accompany your book’s listing on online sites like Amazon and Book Depository. The book description will often include the back book blurb text plus endorsements and reviews (much like the entire back cover of a book). If you don’t have a print version of your book and it’s only sold online, everything in this article about back book blurbs can be applied to your book description in online listings.