Most research papers in the arts and humanities require use of primary and secondary sources for critical analysis and support of ideas. But what is a primary source and what is a secondary source? Figuring this out can be complicated!
What is a Primary Source?
The Reference and User Services Association (RUSA) of the American Library Association offers a historical definition of a primary source, to wit:
"primary sources are original records created at the time historical events occurred or well after events in the form of memoirs and oral histories." [RUSA, "Using Primary Sources on the Web," accessed January 2014 through http://www.ala.org/rusa/sections/history/resources/pubs/usingprimarysources]
Another useful definition is provided by Sylvan Barnet, who describes primary sources as the subject of study, and secondary sources as materials written about the primary sources. [Sylvan Barnet, A Short Guide to Writing About Art (New York: Pearson/Longman, 2005), 240.]
Some Examples of Primary Sources
Ordinarily, a primary source is thought of as being unique, such as, for example:
an object, a letter, a photograph, an art work, a city plan.
an archival collection, such as someone's papers or office records.
The reality is, however, that not all primary sources are unique. Some have been republished or reproduced multiple times. Here are some examples:
a newspaper article that first reported on an event.
a creative or theoretical work, such as, for example, the architect Le Corbusier's book Urbanisme, first published during his lifetime in the 1920s, and translated into English fairly soon thereafter as The City of Tomorrow and Its Planning. Editions of this work, both in the original French and in translation, may constitute a primary source, depending on the context in which they are used.
The context of your research is very important in defining what are primary and secondary materials. If you are writing a critical course paper on Le Corbusier's ideas for city planning, any translation of his book The City of Tomorrow and Its Planning may be used as a primary source. If, however, you are writing about the development of Le Corbusier's planning thoughts and on the dissemination of his ideas, you will likely have to use a particular edition for your research. Given this more specific historic context of your research, early editions in French and other languages may constitute your primary sources, whereas the later editions may not be as relevant to your study, or might be used as secondary resources.
What is a Secondary Source?
Regardless of what "primary" source is appropriate for the context of your research project, your and others' critical analysis of it are secondary sources.
I highly recommend the USC Libraries Primary Source Guide for information on collections of primary resources and recommendations for evaluating primary sources.