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Primary Sources: Home

What is a Primary Source?

Primary sources are those which were either created during the time period being studied or were created at a later date by a participant in the events being studied (memoirs, for example).  They reflect the individual viewpoint of a participant or observer.  Primary sources enable the researcher to get as close as possible to what actually happened during an historical event or time period.


  • Original documents and records (e.g. governmental records and certificates)
  • Data sets and statistics
  • Original correspondence, including email
  • Empirical studies (research based on scientific and experimental results)
  • Technical reports
  • Dissertations and theses (when based on original research)
  • Learning objects
  • Autobiographies and diaries
  • Original works of art and literature
  • Interviews, surveys and fieldwork documentation
  • Photographs
  • Tests, scales
  • Course materials and syllabi
  • Medical charts
  • Student records (i.e., report cards)

In the sciences, primary sources are original materials that have not been filtered through interpretation or evaluation by a second party.  Examples include conference papers, dissertations, interviews, laboratory notebooks, patents, a study reported in a journal article, a survey reported in a journal article, and technical reports.

What is a Secondary Source?

A secondary source is a work that interprets or analyzes an historical event or phenomenon. It is generally at least one step removed from the event and is often based on primary sources.


  • Bibliographies
  • Biographies and historical accounts
  • Commentaries
  • Dictionaries and encyclopedias
  • Journal articles (sometimes primary)
  • Monographs (other than fiction, poetry, autobiography)
  • Textbooks
  • Works of criticism and interpretation
  • Handbooks
  • Chronologies
  • Almanacs and fact books
  • Directories
  • Review articles and editorials
  • Digests and summaries
  • Data tables and summaries

In the sciences, a secondary source would be a book or an article  that analyzes or comments on the results of original research.

Evaluating Web Sources

When using primary sources from the web, make sure that you have found a trustworthy website.

What If I'm Not Sure About My Source?

Disciplines vary when distinguishing between primary and secondary sources. Definitions that pertain to the Humanities and Social Sciences are quite different from those that apply to the Sciences.

If you're not sure whether something is a primary source, check with your instructor and/or consult a librarian.


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