When your professor uses the term, primary source, it can mean something different depending on the discipline, but it usually refers to a source created in a direct manner. Below, I'll define a primary sources in a few ways so that you get a well rounded idea of how the term is used.
Why would I use these sources in my research?
Primary sources offer a first-hand or eyewitness account of a situation that is unfiltered by interpretation.
How should I use them in my research?
To analyze primary sources, ask yourself these questions:
Secondary sources are interpretations and evaluations of primary sources. They are analyses of primary sources written by scholars and experts in a field after the time period or event has occurred.
Why would I use them?
Secondary sources have the benefit of hindsight. The author is able to contextualize the primary source in a way that takes into account other viewpoints and events that happened at the same time or afterwards.
Where are some examples?
How should I use them in my research?
Secondary sources are useful when you need an expert’s or scholar’s interpretation of a topic. This individual has spent her career researching primary documents and interpreting, analyzing and contextualizing them.

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