Primary sources are original accounts or documents around an event.
Secondary sources include some level of interpretation.
What is "primary" depends on the context of your research. The tutorial "Wheel of Sources" provides very helpful information on distinguishing the two in different scenarios. When in doubt, check in with a librarian or instructor.
Tip: If you are reading a secondary source and they mention a primary source of interest... track down that primary source! Maybe it's an image you want to use or the text of a speech or a letter.
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