Primary Sources

• The categories of primary, secondary, and tertiary sources are not mutually exclusive. 
• The way one uses or interprets an item determines whether it is a primary or secondary source. 
• A book can be treated as an artifact, documents can consist of visual elements, and visual materials are often considered to be documents.
• Think of primary sources as the raw data for your research and consider this example:  Encyclopedias are usually considered to be classic reference sources.  However, they are primary sources to someone studying encyclopedias.

1) Primary Sources

• Materials that contain direct evidence, first-hand testimony, or an eyewitness account of a topic or event under investigation
• Primary sources provide the raw data for your research
• Examples:  In addition to diaries, correspondence, photographs, and many other types of sources typically considered to be primary sources, you may add just about anything to the list.  The way you interpret or use a source determines whether it is a primary source or not.

2) Secondary Sources

• Use primary data to solve research problems
• Examples:  scholarly books and articles
• Secondary sources can be interpreted as primary sources when the artifactual characteristics of the item are of research value.

3) Tertiary Sources

• Books or articles that synthesize and report on secondary sources for general readers
• Examples:  textbooks, encyclopedia articles, Wikipedia

Solid research requires the use of all three types of sources.  Primary sources will provide the raw data for your research, but you will also need encyclopedias, dictionaries, subject guides and other reference tools to gather background information on your topic and to identify the people, places, dates, organizations, and themes central to your topic. 

Secondary sources such as books, scholarly journals, and newspaper articles synthesize current research and help put your subject in context.  Secondary sources are also important for helping to position your own argument within the scholarly conversation on your topic.  

Use library catalogs, databases, printed reference sources, the web, and the assistance of your subject librarian to identify, locate, and use primary, secondary, and tertiary sources.

Adapted from The Craft of Research by Wayne C. Booth, Gregory G. Colomb, Joseph M. Williams.  Chicago: University of Chicago Press, c2008.

The following list contains examples of the many formats of items that may be considered primary sources.  Thinking of these different categories of materials can help you imagine the various sources that might be available to you in your research.  Note that the same piece of evidence may be a primary source in one investigation and a secondary source in another.  Be creative in thinking about primary sources and adapt your search strategy to find specific formats of materials. 

• Books and monographs
• Correspondence (email, text messages, postcards, letters)
• Dissertations
• Government documents (reports, census data, testimony, laws, treaties)
• Machine readable data files
• Manuscripts and Archives, whether personal or family papers or  organizational records
• Maps, architectural plans, and schematics
• Moving Image Materials
• Music
• Objects and Artifacts
• Printed Ephemera (leaflets, flyers, handbills, etc.)
• Serials, including newspapers, periodicals, magazines, and scholarly  journals
• Broadcast media, including tv and radio
• Sound Recordings
• Visual materials (prints, photographs, posters, artworks)