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Information Literacy: Primary Sources

This guide will explain how information is classified.

Primary, Secondary, or Tertiary?

Another way to categorize information is whether it is primary, secondary or tertiary. In many classes you will be asked to use primary sources for assignments.


A Primary source of information is first-person, original information.


  • a journal or diary
  • original research
  • interview
  • letter
  • speech
  • original work of art
  • government document
  • research article from a variety of databases and web sites


A Secondary source of information is material that has been taken from primary sources and then synthesized.


  • college textbook
  • biography
  • criticism
  • historical study
  • journal or magazine article that reviews original works


A Tertiary source of information consists of secondary sources, such as books and articles that have been gathered together in an index or database.


  • Cuesta Library Search, which gathers the books, videos, and more available in the library
  • online database, which indexes articles from numerous journals
  • encyclopedia
  • bibliography
  • dictionary
  • almanac