Primary Sources are immediate, first-hand accounts of a topic, from people who had a direct connection with it. Primary sources can include:
Secondary Sources are one step removed from primary sources, though they often quote or otherwise use primary sources. They can cover the same topic, but add a layer of interpretation and analysis. Secondary sources can include:
When is a Primary Source a Secondary Source?
Whether something is a primary or secondary source often depends upon the topic and its use.
A biology textbook would be considered a secondary source if in the field of biology, since it describes and interprets the science but makes no original contribution to it.
On the other hand, if the topic is science education and the history of textbooks, textbooks could be used a primary sources to look at how they have changed over time.
Examples of Primary and Secondary Sources
*Content borrowed from The University of Massachusetts Boston Healy Library's Primary Sources: A Research Guide.