BOOK originated from the old word 'Bōc'. The Saxon and Germanic tribes of medieval Europe engraved lune characters on the boards of beech trees, which were then recorded as 'boke'. It was later derived as 'buch' in German, 'boek' in Dutch, and 'book' in English. Over the years, books have been transformed into bundles of information recorded by the appearance of papyrus, parchment, and paper, but it is undeniable that books began in those days when trees were the source of life and the universe.
There is life in the book. That's why you have to bear in mind that a small mistake can hurt many trees when you make a book. Therefore, a book designer needs to understand the structure of a book and to communicate through correct terms. The poster focused on the hardcover version because this type of book is the origin of most modern books and have for a variety of terms.