Primary sources are first-hand accounts by participants of a particular event or materials produced at the same historical time period.
If you were examining racism in the 1911 edition of the Encyclopaedia Britannica, the article in the encyclopedia on the "Negro" would be a primary source. However, an article in the American Historical Review analyzing racism in the Britannica would be a secondary source. (Richard Marius, A Short Guide to Writing About History, pp. 14-15.)
Some examples of primary sources include:
Secondary sources interpret or analyze primary sources. Thus, they are a step removed from the event or original text. Examples of secondary sources include:
How you use a source determines whether it is a primary source or secondary source. If you are analyzing a magazine article from the 1940s to talk about what life was like during that time period, it is a primary source. However, if you are citing information from a magazine article written today about the 1940s, then it is a secondary source.
Credit: Jessup Library, Piedmont Virginia Community College