Bookbinding is the process of physically assembling a book from an ordered stack of paper sheets that are folded together into sections or sometimes left as a stack of individual sheets. The stack is then bound together along one edge by either sewing with thread through the folds or by a layer of flexible adhesive. For protection, the bound stack is either wrapped in a flexible cover or attached to stiff boards. Finally, an attractive cover is adhered to the outside surface and identifying information printed on the spine.
There are several different methods of binding books, each with its own advantages and disadvantages. Sewn bindings are generally more durable than glued bindings but require more time and effort to create. Glued bindings can be quicker and easier to produce but may not hold up as well over time. Comb binders use plastic combs to hold pages together, while wire binders use metal wires looped through holes punched along the spine. Loose leaf rings allow pages to be added or removed easily, while twin loops create two loops of wire along the spine for extra durability.