How to Research: Primary vs. Secondary Sources

Primary sources are original materials. They are from the time period involved and have not been filtered through interpretation or evaluation. 

Examples:

• Artifacts (e.g. coins, plant specimens, fossils, furniture, tools, clothing, all from the time under study);
• Audio recordings (e.g. radio programs);
• Internet communication on email, twitter, social media, etc.;
• Interviews (e.g., oral histories, telephone, e-mail);
• Journal articles published in peer-reviewed publications;
• Letters;
• Newspaper articles written at the time;
• Original Documents (i.e. birth certificate, will, marriage license, trial transcript);
• Proceedings of Meetings, conferences and symposia;
• Records of organizations, government agencies (e.g. annual report, treaty, constitution, government document);
• Survey Research (e.g., market surveys, public opinion polls);
• Video recordings (e.g. television programs);

From: "Primary, Secondary and Tertiary Sources." University of Maryland, University Libraries. 1 March 2013. Web. 3 October, 2013.

Secondary sources are accounts written "after the fact" and with the benefit of hindsight (greater understanding of the incident).  They are normally interpretions and evaluations of primary sources. Secondary sources are not evidence, since they provide commentary on and discussion of the evidence. 

• Bibliographies
• Biographical works
• Reference books, including dictionaries, encyclopedias, and atlases
• Articles from magazines, journals, and newspapers after the event
• Literature reviews and review articles (e.g., movie reviews, book reviews)
• History books and other popular or scholarly books
• Works of criticism and interpretation
• Commentaries and treatises
• Textbooks
• Indexes and abstracts

From: "Primary, Secondary and Tertiary Sources." University of Maryland, University Libraries. 1 March 2013. Web. 3 October, 2013.