More information on the binding spine
The binding is often flexible, making the book easy to open and read. The thickness of the binding usually indicates the size of the book: the more pages, the wider the spine. The spine often contains information such as the title of the book, the name of the author and sometimes the publisher's logo. This information makes it easy to identify the book when it is on a shelf with the spine facing out.
In addition, the binding can also be a wire-o ring binder, which can also hold the pages together. Although this is a very different form of binding, the wire-o spiral is still the “spine” of the book.