Books are classified by a [[hierarchy]]. The two most general categories of this hierarchy are [[fiction]] - meaning an invented or feigned narrative
, an imaginative form of narrative - and [[non-fiction]] - a composition that its authors believe to be truthful.
Books can also be classified by media, such as audio or print. For example, some books are available in audio versions. An example of this is [[Talking Books]], available through the free Talking Books Program through the [[Library of Congress]].