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Political Science 194H (Carey, Spring 2025)

Senior Honors Thesis Seminar

Source Types Comparison

The primary sources are where original research is reported. That information, over time, makes its way into secondary sources, while the tertiary sources are the resources used to search primary/secondary sources.

Primary, Secondary and Tertiary Sources

Primary sources provide first-hand observations or direct evidence concerning a topic under investigation. They are created by witnesses or recorders at or near the time of the event. They have not been filtered through further interpretation or evaluation. 

Primary sources may include

  • Original Documents: diaries, speeches, letters, interview transcripts, news footage, autobiographies, reports, census records, data from an experiment
  • Creative Works: poetry, plays, novels, music scores, films, paintings
  • Objects: clothing, buildings, tools, furniture

Secondary sources are works that analyze, assess or interpret a historical event, era or phenomenon.  They may use primary sources to to write a review, critique or interpretation often well after the event.

Secondary sources may include

  • journal articles, editorial articles, literacy criticism, book reviews, biographies, textbooks

Tertiary Sources are those used to identify and locate primary and secondary sources.

Tertiary sources may include

  • Reference Works: encyclopedias, abstracts
  • Lists or Collections: bibliographies, finding aids
  • Search Tools: library database or catalog, indexes

Primary, Secondary, and Tertiary Sources

Beyond definitions of primary, secondary and tertiary source types, this video provides useful examples of what would be primary, secondary and tertiary sources for research questions in different disciplines. See 1:48.

(2:33) Suffolk County Community College (SCCC) Library