When determining whether or not to use a source for your paper, knowing the quality of the source is essential. The quality of a source is based on the type of source: Primary, Secondary, and Tertiary.
Confederate States of America Certificate. A 9000 dollar Confederate bond made out to Saua Towner. This is number 197. Engraved by Hoyer and Ludwig, 1862. Delaware Heritage Collection, Courtesy of the Milford Museum.
A Primary source is an original document, art, or object that was created during the time under study. These sources are considered the most reliable, as they are directly from the time being referenced, and thus contain first-hand accounts that are not modified by interpretation. These sources are useful for evidence within an essay, due to their reliability.
Examples of Primary sources are diary entries, letters, interviews, scientific reports, archeological artifacts, and photographs.
Delaware Historical Society newsletter Making history
A Secondary source is a document, art, or object that is one step removed from a Primary source, and usually references one. These sources are considered less reliable, as they are not from the time being studied and instead interpret Primary sources. However, they can be incredibly useful for the analysis and interpretation of topics as a way to view the event in different contexts.
Examples of Secondary sources are scholarly articles, histories, criticisms, reviews, and biographies.
A Tertiary source is an index of Primary and Secondary sources that organizes but does not interpret the sources. These sources, although fairly reliable, are not the best to specifically reference in an essay due to their lack of specialized knowledge. Instead, these sources are useful for behind-the-scenes work on essays, and for finding Primary and Secondary sources.
Examples of Tertiary sources are almanacs, bibliographies, manuals, textbooks (can be secondary), and encyclopedias.