Scope: As you conduct research, you will consult different sources of information. A professor may request primary, secondary, or tertiary sources. What does that mean? This guide explains these terms and gives examples for each category. Contact a subject specialist librarian in User Education Services for more information.
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.
the compact fluorescent light bulb would be a secondary source.
popular media, the magazine article could be considered a primary source.
Primary sources are original materials. They are from the time period involved and have not been filtered through interpretation or evaluation. Primary sources are original materials on which other research is based.
They are usually the first formal appearance of results in physical, print or electronic format.
They present original thinking, report a discovery, or share new information.
Note: The definition of a primary source may vary depending upon the discipline or context.
- Artifacts (e.g. coins, plant specimens, fossils, furniture, tools, clothing, all from the time under study)
- Audio recordings (e.g. radio programs)
- Internet communications on email, listservs
- Interviews (e.g., oral histories, telephone, e-mail)
- Journal articles published in peer-reviewed publications
- Newspaper articles written at the time
- Original Documents (i.e. birth certificate, will, marriage license, trial transcript)
- Proceedings of Meetings, conferences and symposia
- Records of organizations, government agencies (e.g. annual report, treaty, constitution, government document)
- Survey Research (e.g., market surveys, public opinion polls)
- Video recordings (e.g. television programs)
- Works of art, architecture, literature, and music (e.g., paintings, sculptures, musical scores, buildings, novels, poems)
- Web sites
Secondary sources are less easily defined than primary sources. Generally, they are accounts written
after the fact with the benefit of hindsight. They are interpretations and evaluations of primary sources.
Secondary sources are not evidence, but rather commentary on and discussion of evidence.
However, what some define as a secondary source, others define as a tertiary source. Context is everything.
Note: The definition of a secondary source may vary depending upon the discipline or context.
- Bibliographies (also considered tertiary)
- Biographical works
- Commentaries, criticisms
- Dictionaries, Encyclopedias (also considered tertiary)
- Journal articles (depending on the disciple can be primary)
- Magazine and newspaper articles (this distinction varies by discipline)
- Monographs, other than fiction and autobiography
- Textbooks (also considered tertiary)
- Web site (also considered primary)
Tertiary sources consist of information which is a distillation and collection of primary and secondary sources.
- Bibliographies (also considered secondary)
- Dictionaries and Encyclopedias (also considered secondary)
- Fact books
- Indexes, abstracts, bibliographies used to locate primary and secondary sources
- Textbooks (also be secondary)