paperback
A book generally defined as a flat back book with
a paper cover that is usually, but not always, of
a heavier stock than that used for the leaves of
the publication itself. Paperback books are often
made up of single leaves secured by a hot-melt
adhesive. They usually have relatively narrow
binding margins, are often printed on paper of
poor to very poor quality (frequently with a high
proportion of mechanical wood pulp), and are
generally cut flush. (123 )