Introduction to Archival Research: Types of primary sources

A primary source can be anything that gives direct evidence of a topic or event. 

In contrast, a secondary source may use primary evidence to analyze, interpret, explain, or comment on that topic or event. 

Importantly, whether a source is considered primary or secondary depends on the way you engage with it. For example: 

• History textbooks are secondary sources if you use them to study an historical period. However, if you use a collection of history textbooks to study the ways the American Civil War has been taught in schools in different periods over time, they would be primary sources, providing direct evidence of the way the Civil War is presented in different educational resources.

Often, when we think of primary sources, we think of things created for the explicit purpose of documenting a fact or event for posterity. These can include: 

• diaries and personal letters
• autobiographies
• interviews and oral histories
• written reports 
• court records and transcripts
• official documentation, like birth certificates, legal contracts, and affidavits

However, primary sources also include documents and materials created in the regular course of our lives and work that can now be used as direct evidence of the who, what, where, when, and why of the things we did. These unexpected sources of evidence can include: 

• creative work, including music, art, creative writing, and poetry
• financial ledgers and business memos
• original research data
• advertisements, posters, and catalogs
• event programs
• technical manuals
• maps and architectural drawings 
• educational materials
• media and social media
• objects, clothing, and other artifacts

Image credits: Material from Emma Fairhurst papers and George Nace papers, University of Colorado Boulder Libraries