Types of Sources

Your professor may have asked you to use primary sources for a research paper.  This guide will help you become familiar with the three main types of sources.

Primary Sources

• Original documents with no interpretation, evaluation, or analysis
• Original documents created contemporaneously with the event under discussion
• Reflects the individual viewpoint of a participant or observer.
• Usually found in library or manuscript collections. Many have also been copied onto microfilm, published, reissued, translated, or, in some instances, published digitally on the web.
• The research librarians can assist you in locating primary sources.

Examples of primary sources:

• Books, magazine and newspaper articles published at the time
• Speeches, interviews, letters, memoirs, autobiographies
• Public opinion polls
• Artifacts of all kinds: physical objects, furniture, tools, clothing, etc.
• Photographs, audio recordings, movies and videos

Secondary Sources

• Sources that interpret, evaluate, or analyze a primary source
• At least one step removed from the event.

Examples of secondary sources:

• Articles in scholarly journals that interpret literary or art works, historical events or persons. See "Types of Periodicals."
• Commentaries and annotations accompanying the primary sources in the same volume.  These are often referred to as critical editions.
• Books summarizing, synthesizing, or retelling historical events
• Biographies, critical works, commentaries

Tertiary Sources

• Sources that compile, summarize, digest, or index secondary sources

Examples of tertiary sources:

• Print or online indexing and abstracting resources, such as: Sociological Abstracts, MLA Bibliography, PsychInfo, Expanded Academic Index
• Reference works, such as encyclopedias, dictionaries, atlases, handbooks, chronologies
• Book-length bibliographies