The document introduces books as a topic that will be discussed. It states that books have leaves but are not trees and can be good friends though they are not alive. The document then divides literature into fiction and non-fiction genres. It lists several fiction genres like poetry, detective stories, short stories, and fairy tales. It also lists several non-fiction genres like encyclopedias, atlases, reference books, reports, and dictionaries. Finally, it provides a short description of detective stories as involving criminals that are caught by clever detectives.