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Library Research E-Textbook - Student Version: Primary vs. Secondary Sources

Introduction & Goals


Primary vs. Secondary Sources: Primary sources are first-hand accounts of an event (such as a historical occurance) or phenomenon (such as a scientific study), while secondary sources interpret and analyze primary sources.


By the end of this module, you will understand what primary and secondary sources are, and the basics of how to locate them.

Video on Primary vs. Secondary Sources

Watch this video to learn how to identify the differences between primary and secondary sources. 

Primary and Secondary Sources

To complement what you learned in the video above, please read through the following information:

When your teachers say "primary source," what do they mean? Usually this term refers to a document or record containing firsthand information or original data on a topic. Primary sources include original manuscripts, articles reporting original research or thought, diaries, memoirs, letters, journals, photographs, drawings, posters, film footage, sheet music, songs, interviews, government documents, public records, eyewitness accounts, newspaper clippings, etc.

By contrast, a secondary source is a document or recording that relates or discusses information originally presented elsewhere. A secondary source contrasts with a primary source, and involves generalization, analysis, synthesis, interpretation, or evaluation of the original information.

There was a time when the only way to use primary sources was to travel all over the country (or the world) visiting museums, historical societies, and libraries with rare materials. Scholars had to obtain research grants and permission to use these collections.

Then came microfilm. Microfilm is a format that involves a photograph being taken of an item, which is then shrunk down and transferred to a plastic film that can be easily stored and reproduced. 

Sometimes the only way to use primary source materials is to travel or to muddle through the microfilm, but more and more often, important materials are being digitized.  Some of these materials are being made available for a fee, but others are out there free of charge. Make sure to search for digital collections that may be relevant to your research.

Some interesting examples of digitized collections are:

100 Milestone Documents, from Our Documents at the National Archives: This collection of 100 milestone documents has been compiled by the National Archives and chronicles the history of the U.S. from 1776 to 1965. Sources include public laws, Supreme Court decisions, inaugural speeches, treaties, constitutional amendments, and other documents that have influenced the course of U.S. history. Both original and transcribed copies are available.

The Avalon Project, from the Yale Law School: This collection, which can be viewed chronologically from the fifteenth century to the twenty-first, includes documents selected for their importance in American legal history. Sources can also be searched by themed “Document Collections”.

Docs Teach, from the National Archives: This collection of over 3,000 primary documents is organized by historical era, from the nation’s founding to the present. Documents, including maps, charts, graphs, audio, and video, have been selected by National Archives Staff, and are photographic reproductions of historical sources.

Many Pasts, from the History Matters project of CUNY Graduate Center and George Mason University: This feature of George Mason University’s History Matters project features prepared and selected primary documents in text, image, and audio about the experiences of ordinary Americans throughout U.S. history. The “full search” feature on the site allows users to choose resources by historical period, topic, type of resource, etc.

Smithsonian Source, from the Smithsonian Institute: This collection of primary sources can be searched by keyword, type, or topic, and includes documents on Westward Expansion, Transportation, Civil Rights, Invention, Colonial America, and Native American history. Each set includes selected and excerpted documents.

Comparing Sources

Print and read the following worksheet outlining what types of documents are primary sources, and what types are secondary sources.


Click here to proceed to the next page of the module, Information Life Cycle & Source Types.