The materials, evidence, or data used in your research are known as sources. As foundations of your research, these sources of information are typically classified into two broad categories— primary and secondary.

Primary Sources

A primary source provides direct or firsthand evidence about an event, object, person or work of art. Characteristically, primary sources are contemporary to the events and people described and show minimal or no mediation between the document/artifact and its creator. As to the format, primary source materials can be written and non-written, the latter including sound, picture, and artifact. Examples of primary sources include:

  • personal correspondence and diaries
  • works of art and literature
  • speeches and oral histories
  • audio and video recordings
  • photographs and posters
  • newspaper ads and stories
  • laws and legislative hearings
  • census or demographic records
  • plant and animal specimens
  • coins and tools

Secondary Sources

A secondary source, in contrast, lacks the immediacy of a primary record. As materials produced sometime after an event happened, they contain information that has been interpreted, commented, analyzed or processed in such a way that it no longer conveys the freshness of the original. History textbooks, dictionaries, encyclopedias, interpretive journal articles, and book reviews are all examples of secondary sources. Secondary sources are often based on primary sources.

Primary and Secondary Sources Compared

An example from the printed press serves to further distinguish primary from secondary sources. In writing a narrative of the political turmoil surrounding the 2000 U.S. presidential election, a researcher will likely tap newspaper reports of that time for factual information on the events. The researcher will use these reports as primary sources because they offer direct or firsthand evidence of the events, as they first took place. A column in the Op/Ed section of a newspaper commenting on the election, however, is less likely to serve these purposes. In this case, a columnist’s analysis of the election controversy is considered to be a secondary source, primarily because it is not a close factual account or recording of the events.
Bear in mind, however, that primary and secondary sources are not fixed categories. The use of evidence as a primary or secondary source hinges on the type of research you are conducting. If the researcher of the 2000 presidential election were interested in people’s perceptions of the political and legal electoral controversy, the Op/Ed columns will likely be good primary sources for surveying public opinion of these landmark events.

The chart below illustrates possible uses of primary and secondary sources by discipline:

Discipline Primary Source Secondary Source
Archaeology farming tools treatise on innovative analysis of neolithic artifacts
Art sketch book conference proceedings on French Impressionist
History Emancipation Proclamation (1863) book on the anti-slavery struggle
Journalism interview biography of publisher Katherine Meyer Graham
Law legislative hearing law review article on anti-terrorism legislation
Literature novel literary criticism on The Name of the Rose
Music score of an opera biography of composer Georges Bizet
Political Science public opinion poll newspaper article on campaign finance reform
Rhetoric speech editorial comment on Martin Luther King’s “I Have a Dream” speech
Sociology voter registry Ph.D. dissertation on Hispanic voting patterns

Primary Source Searching in IUCAT

Use the IU online library catalog (IUCAT) to look for primary source materials.
Employ the Library of Congress subject heading subdivisions below to retrieve primary materials from IUCAT. These subdivisions indicate the form in which the material is organized and presented.

Subject Heading Subdivisions
Anecdotes diaries pictorial works
Archives documentary films portraits
Biography exhibitions public opinion
caricatures and cartoons interviews songs and music
case studies manuscripts sources
Catalogs maps speeches
comic books, strips notebooks, sketchbooks statistics
correspondence personal narratives statues
description and travel photography  

Primary Source Search Examples

Use the subject subdivisions to build search statements that may include names, events or topics. Below is a select sample of library catalog searches. Enter these terms and search for as Subject in IUCAT. You may also wish to try search for a ALL Fields which will give you a larger but less focused result. Use the AND operator (or the + sign) to combine ideas; for example, novelists and correspondence. AND will find your search words in any section of the subject headings and will increase the likelihood that you will find relevant material.

To search for document collections

feminism AND history AND sources
Roosevelt Franklin AND archives
Vietnam AND foreign relations AND sources

To search for oratory and speeches

American AND speeches
Douglass Frederick AND speeches
statesmen AND speeches

To search for interviews, personal accounts, and letters

novelists AND correspondence
rap musicians AND interviews
working class women AND diaries

To search for pictorial works

inscriptions AND Greece AND catalogs
documentary photography AND Salgado Sebastião AND exhibitions
painting AND Australian aboriginal AND exhibitions

To search for commercial and advertising art

advertising AND catalogs
advertising AND collectibles AND catalogs
commercial art AND catalogs

To search for film and documentaries

biographical films AND Mahatma Gandhi
documentary films AND race relations
documentary films AND sports