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Research Guides

Primary Sources vs Secondary Sources


Primary Source Secondary Source
DEFINITION:  A document that fully describes original research written by those that conducted that original research.   DEFINITION:  A document that contains commentary, interpretation, and/or analysis of original research. 
EX:  Academic journal article where researchers describe their own research and experimentation regarding enzymes in bovine liver. European Journal of Biochemistry EX:  Popular magazine blog post that comments on multiple studies regarding the impact of sleep on regulating emotions. Psychology Today

Helpful Slide


Primary Source Secondary Source

DEFINITION:  a document, image, or artifact created during the time-period under investigation. (Also called a direct source.)

DEFINITION:  A document created after the time-period under investigation that interprets, analyzes, or summarizes a primary source(s).
EX:  the "I Have a Dream" speech by Martin Luther King Jr,  EX:  an academic journal article analyzing King's speech.

Tertiary Sources

These are sources that summarize, list, or organize ideas.  Tertiary sources do not analyze or interpret primary sources.  A tertiary source is the furthest removed from a primary source.

Examples include:  Wikipedia, encyclopedias (may be secondary), textbooks (may be secondary), dictionaries, guidebooks, manuals.  


Note:  If any source is analyzing a primary source, it is secondary, not tertiary.

Examples of Primary and Secondary Sources (Science & Humanities)

Primary Sources Secondary Sources
  • Academic journal article of original research
  • Conference Papers
  • Correspondence
  • Dissertations
  • Diaries
  • Interviews
  • Lab Notebooks
  • Notes
  • Patents
  • Proceedings
  • Studies or Surveys
  • Technical Reports
  • Theses
  • Newspaper/magazine articles written soon after event (not historical accounts)
  • Popular magazine articles 
  • Academic journal article
  • Criticism and Interpretation
  • Dictionaries (may be tertiary)
  • Encyclopedias (may be tertiary)
  • Government Policy
  • Public Opinion
  • Reviews
  • Social Policy

adapted from University at Albany Library

Recommended Sites for Finding Primary Sources on US History

  • African American History Primary Sources:  A LibGuide from the University of Washington listing primary sources on African American History.
  • American Women:  Library of Congress research guide focused on Women's History.  Click "keyword" to get to the keyword search page.
  • Chronicling America:  A joint project of the Library of Congress and the National Endowment for the Humanities.  Currently, you can search and view pages from the newspapers of around 30 states. The ultimate goal of this project is to have every state and U.S. territory represented in this digital archive.  Coverage is 1836 to 1922 but varies by title.
  • Documenting the American South: A site from the University of North Carolina at Chapel Hill covering Southern history, literature and culture from the colonial period through the first decades of the twentieth century, this site provides access to an outstanding collection of materials including first person and slave narratives.
  • The Library of Congress's Digital Collections:  Digitized documents and artifacts on American history and culture from the collections of the Library of Congress. 
  • The Making of America (Cornell) and the Making of America (Michigan):   Full-text access to primary sources in American social history from the antebellum period through reconstruction. This includes digitized books and long runs of journals. A collaboration between Cornell University and the University of Michigan, each site provides access to the other. 
  • Digital Public Library Primary Source Sets:  Sets of primary sources organized by subject or time period.
  • Library of Congress Primary Source Sets:  Sets of primary sources organized by subject.
  • Valley of the Shadow:  A collaboration between the Virginia Center for Digital History and the University of Virginia Library, explores life during the American Civil War era in two towns, one Southern and one Northern.
  • Veterans' Oral History Project:  A collection of US veterans' interviews and images