Primary sources-- These come first in the publication cycle: objects, original documents or materials containing firsthand information about a topic. They are often one-of-a-kind or rare. When searching Library databases for these materials use the words "sources" or "documents" in combination with your topic. (i.e. slavery and sources).
autobiography / diaries / personal narrative / correspondence
description and travel / pictorial works / interview / news
fiction / poetry / short stories
Secondary sources-- tend to come second in the publication cycle and are about an event or primary source. Secondary sources describe, interpret, analyze, evaluate, explain, comment on, or develop theories related to the primary source. They are written after the fact, with hindsight.
scholarly periodicals and books / Articles in scholarly publications / social policy / law & legislation / criticism and interpretation / teaching & study
Tertiary sources-- tend to come last in the publication cycle. Generally called "reference." These works list, compile, digest or index primary or secondary sources. They can be a good place to look up facts or get a general overview of a subject.
bibliography / dictionaries / encyclopedias / guidebooks / handbooks, manuals, etc. / DSM5 & International Statistical Classification of Diseases
