What are primary sources?

  • Primary sources provide first-hand testimony or direct evidence concerning a topic under investigation. They present original thinking, report a discovery, or share new information.
  • They are created by witnesses or recorders who experienced the events or conditions being documented. They are from the time period involved and have not been filtered through subsequent interpretation or evaluation.

How do I know what type of source I need?

Talk to your instructor. Determining what is a primary source can be tricky and depends on the topic, subject, and discipline you are researching. The types of information that can be considered primary sources may vary depending on the subject or discipline. Also how you are using the material in your paper or project can effect this determination. For some papers or projects it may be important to view the original object but for others a primary source that has been scanned and is online is acceptable.

History, Humanities, Social Sciences

Primary sources in these disciplines are original records created at the time historical events occurred or well after events in the form of memoirs and oral histories.

Examples include: Letters, manuscripts, diaries, rare books, historical photographs, first-hand accounts or documentary sources on a subject, person, event or issue; newspapers written at the time of an event, song, or film from time period, historical maps, government reports or data, etc.

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Health Sciences, Sciences, Engineering

Primary sources in the sciences are original materials or information on which other research is based. Primary sources are also sets of data, such as health statistics, which have been tabulated, but not interpreted.

Examples include: Journal articles of original research (written by person who did the research), patents, conference papers, dissertations, technical reports, Einstein’s diary

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Context is important

The types of information that can be considered primary sources may vary depending on the subject discipline, and also on how you are using the material. For example:
  • A magazine article reporting on recent studies linking the reduction of energy consumption to the compact fluorescent light bulb would be a secondary source.
  • A research article or study proving this would be a primary source.
  • However, if you were studying how compact fluorescent light bulbs are presented in the popular media, the magazine article could be considered a primary source.
Tip: If you are unsure if a source you have found is primary, talk to your instructor, librarian or archivist.

What are secondary sources?

  • Secondary sources are interpretations and evaluations of primary sources
  • Secondary sources are not evidence, but rather commentary on and discussion of evidence.
  • Books, articles, etc. which use primary sources as the source would be secondary.