CTX Research Guides: Primary and Secondary Sources: Primary and Secondary Sources

Defining primary vs. secondary sources

A primary source is a document created during the time period of your research subject, about your research subject. These documents are directly connected with the events or people being researched. A secondary source is a document created at a later time period, often much later than the time period of the event being researched, by someone who did not experience said event. These documents have no direct personal connection with the events or people being researched, but they may benefit from being able to put the event “in context” or perspective.

Chart listing examples of primary and secondary sources.

You may notice that the list of examples for primary sources is longer than for secondary. Don’t let that fool you. While there may be more types of primary sources, secondary sources are the majority of documents you will come across in everyday life.

Primary Sources Secondary Sources

Data and Original Research	Encyclopedias
Diaries and Journals	Chronologies
Speeches and Interviews	Biographies
Letters and Memos	Monographs (a specialized book or article)
Autobiographies and Memoirs	Most journal articles (unless written at the time of the event)
Books or articles or news stories written at the time of the event	Most published books (unless written at the time of the event)
Government Documents from that period	Abstracts of articles
Census Statistics	Paraphrased quotations
Organizational Records from that period	Dictionaries
Documentaries that rely on primary source materials	Textbooks
Photographs	Webpages
Art (from the time period)
Maps (from the time period)
Internet communications (including listservs and emails)
Any of the above reprinted in the original format and language