Primary sources are the raw materials of history — original documents and objects that were created at the time under study.
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The term "primary sources" covers a wide array of resources that serve as a foundational element of many types of research. The key element that distinguishes a "primary source" from others is its originality, as expressed in the quote above.
Types of primary sources include:
Because they offer a first-hand account of what happened, primary documents offer insight into the past and how events influenced people of the time.