Start your research process with the types of sources best suited to your information needs. The tips below will help you identify, compare, and find different types of sources.
TIP: Carefully review your instructor's assignment guidelines. Required source types, quantities, credibility levels, publication dates, etc. may be specified. You may also be advised to avoid certain sources. Clarifying expectations on the front end saves time and effort in the long run. When in doubt, consult your instructor.
Primary sources are original documents, objects, or media created during the time of the event being researched, or by an individual(s) who directly experienced an event, made a discovery, or created a new work of art. They are raw materials with a direct relationship to whatever is being studied.
Examples: photographs, speeches, diaries, editorials, letters, interviews, historic artifacts, works of art, musical scores, performances, literary works, survey research, legal documents, proceedings, patents, video or audio recordings of events being studied, etc.
Secondary sources are a step removed from the original source. They may comment or build upon original primary sources.
Examples: second-hand reports on events, research, or works created by someone else at a different time or place; criticisms; reviews; interpretations; citations; etc.
Tertiary sources typically compile and condense a range of primary and/or secondary sources into an easily-digestible format.
Examples: encyclopedias, almanacs, timelines, bibliographies, directories, fact books, etc. (Note: Many of these are also considered secondary sources.)
Across disciplines, contexts, and perspectives, the definition of primary, secondary, and tertiary sources differ. Some scholars consider encyclopedias secondary sources, while others consider them tertiary sources. In today’s environment of digitized content, most would contend an online image of a primary document or transcript is sufficient, while others might argue the original physical copy is essential for primary research. Like many areas of study, distinctions are fuzzy and subject to interpretation. When in doubt, clarify your instructor’s expectations.