This document defines and provides examples of different types of reference books, including encyclopedias, dictionaries, thesauruses, atlases, and almanacs. An encyclopedia contains articles on a wide range of subjects arranged alphabetically. A dictionary provides definitions, meanings, and pronunciations of words. A thesaurus includes synonyms, related words, and antonyms. An atlas is a collection of maps. And an almanac contains calendars, astronomical data, and other yearly facts.

1. Reference Books Research Materials