Categorizing Sources

In order to determine which information sources best meet your research needs, it is necessary to understand the kind of information generally offered by different categories of sources.

One such category is "primary" vs. "secondary" sources.

When you make distinctions between primary and secondary sources, you are relating the information itself to the context in which it was created. Noting the relationship between creation and context helps us understand the “big picture” in which information operates, and helps us figure out which information we can depend on.

Primary Sources

Primary information sources are firsthand materials in their original form. Examples include:

Eyewitness reports (photographs, interviews)
Memoirs, diaries, oral histories, correspondence
Literary work (novels, plays, poems)
Artwork
Testimony (such as Congressional hearings)
Documentary films
Data, statistics, census reports
Social Media: Tweets, texts, status updates, original blogs

Primary sources often enable the researcher to experience the flavor of the original event or information, rather than relying upon someone else’s interpretation.

Eyewitness photograph: Protesters speak on the steps of San Francisco City Hall for a "Families Belong Together" rally.

Secondary Sources

Secondary sources are created after an event occurred and offer a review or an analysis of the event; they provide an interpretation of the primary source or data without offering new data. Examples of secondary sources would be:

Biographies, nonfiction books
Editorials
Literary criticism and reviews
Periodicals (such as scholarly journals, magazines, or newspapers)
Retweets

Secondary sources can provide valuable interpretation or historical context, provided the sources are trustworthy.

Nonfiction book analyzing the consequences of the construction of physical and virtual walls.

Tertiary Sources

Tertiary sources are compilations of information coming from secondary and primary sources; these can be lists or collections, and are generally reference material that can help you find, or direct you to, secondary and primary sources. Examples of tertiary sources include:

Encyclopedias, dictionaries
Indexes
Databases, catalogs
Most textbooks

wikipedia-screenshot-family-separation-e1609669319846.png

Wikipedia, an online encyclopedia, is an example of a reference source (tertiary).

Citations and Attributions

Content adapted from Library 10 by Cabrillo College Library, licensed under CC BY 4.0

Text: Categorizing Sources adapted from "Primary, Secondary & Tertiary Sources". by Teaching & Learning, Ohio State University Libraries. licensed under CC BY 4.0.

Photograph: "Families Belong Together SF march." by Pax Ahimsa Gethen. is licensed under CC BY-SA 4.0

Book cover: "World of Walls: The Structure, Roles and Effectiveness of Separation Barriers." by Said Saddiki. is licensed under CC BY 4.0.