A primary source is a document providing direct evidence rather than evidence gleaned from the works of others. For historical research, letters, diaries, and newspaper articles written at the time of the event under question would qualify as primary sources. For writing on literature, the work being studied is the primary source. In the sciences and social sciences, the phrase “primary source” may be used to refer to original research.
Primary sources are invaluable for understanding a particular event because they are evidence of real time history (history in the making), at the moment it occurs. They allow you to draw your own conclusions rather than relying on the analysis of experts.
A secondary source interprets or critiques knowledge based on primary sources. They may put primary sources into a broader context, provide further discussion of unclear points, carefully analyze the importance of primary sources, or discuss a primary source in other useful ways.
Examples include most books and periodical articles, as well as reference sources such as encyclopedia entries. Most of the search strategies these tutorials describe are most useful for finding secondary sources. In some cases, primary sources may be difficult to find. If you need sources for primary research, please consult a librarian for further advice.
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