A paperback is a type of book. It has a cover of thick paper or thin cardboard. Paperback book covers can bend and be folded. The covers are laminated (have layers), and some of the methods are more durable (lasting) than others. Another name for paperback is soft cover.
Paperback books may be glued or held by sewing. If the pages are held only by adhesive, the book will eventually come apart. The quality of the paper also varies. It is generally less white than bound hardback books because it is less bleached.
Usually, paperback books cost less money than hardback books. In the middle 20th century a "mass market" type of paperback became commonplace, having a standard size, fitting a standard display rack, and glued.