A primary source is an original object or document from a specific time or event under study. Primary sources include historical and legal documents, interviews, eyewitness accounts, results of experiments, survey data, observations, diaries, paintings, works of literature, ancient pieces of pottery unearthed in Iraq, and much more . In the natural and social sciences, primary sources are often empirical studies — research where an experiment was done or a direct observation was made.
A secondary source is anything that’s written about a primary source, such as an essay about a novel, a newspaper article about AIDS research, a history textbook, a movie review, or subsequent thoughts on The Gettysburg Address.
Tertiary sources use primary and secondary courses to construct a narrative and/or theory.
Can a single source ever be both?
Not really, but it can be confusing. For instance, if I am writing a paper about global warming, a newspaper article that discusses new research on the topic issue is a secondary source. But if I am writing a paper about the media’s coverage of global warming, then the newspaper article is a primary source. What you are studying changes your relationship to the material. To further muddy the water, a secondary source may very well INCLUDE primary source materials in the form of pictures, statistics, or quotes, and that MIGHT work for your teacher, but it might not. Likewise, to ensure accuracy, it is a good practice to track down the primary source if you can just to verify it.
This chart, created by librarians at the Indiana University Bloomington, illustrates kinds of primary and secondary sources by discipline:
||treatise on innovative analysis of Neolithic artifacts
||conference proceedings on French Impressionists
||Emancipation Proclamation (1863)
||book on the anti-slavery struggle
||biography of publisher Randolph Hearst
||law review article on anti-terrorism legislation
||literary criticism on Desolation Angels
||score of an opera
||biography of the composer Mozart
||public opinion poll
||newspaper article on campaign finance reform
||editorial comment on Martin Luther King’s “I Have a Dream” speech
||Ph.D. dissertation on Hispanic voting patterns
The librarians at Princeton also offer a good explanation of this potentially tricky concept.