Primary Source: An authoritative document relating to a subject, which is used in the preparation of a later work, such as an original record or a contemporary document. In the humanities, a primary source is the document being analyzed; in the sciences it is a journal article reporting the results of original research. Primary sources are also called original sources or source material.
Secondary Source: A publication that digests, analyzes, evaluates, and/or interprets the information in primary sources.
Tertiary Source: A source that compiles, analyzes, and/or digests secondary sources.
Timing of Publication
Tends to come first in the publication cycle.
Tends to come second in the publication cycle.
Tends to come last in the publication cycle.
Formats – depends in part on the type of analysis being done and the subject discipline
Newspapers, weekly and monthly magazines, letters, diaries. For scientists, scholarly journal articles.
Scholarly journal articles and books that build upon the primary sources.
Reference books (encyclopedias, for example) or text books.
Example: Historian (studying the Vietnam War)
Newspaper articles, weekly news magazines, monthly magazines, recordings of TV news broadcasts, diaries, letters, and diplomatic records.
Scholarly journal articles and books analyzing the war, which probable footnote the primary sources.
Encyclopedias and other reference books and text books that include information about the Vietnam War.
Example: Literary Critic (studying the literature of the Vietnam War)
Novels, poems, plays, diaries, correspondence.
Scholarly journal articles and books analyzing the literature. Biographies of the authors who wrote the primary sources.
Encyclopedias and other reference books and text books that include information about the literature or the authors.
Example: Psychologist (studying the effects of PTSD)
Article in a scholarly journal that reports original research and its methodology, as well as notes taken by a clinical psychologist.
Scholarly journal articles or books that synthesize the results of original research.
Encyclopedias and other reference books and text books that include information about PTSD.