This document discusses six common types of reference materials: dictionaries, thesaurus, encyclopedia, atlas, almanac, and periodicals. It provides examples of how each reference material is used to look up different types of information, such as word definitions, synonyms and antonyms, biographical facts, maps and locations, current statistics, and more. The document also includes examples of how to determine which reference material would be best to use to find a specific fact or piece of information quickly.