Primary, Secondary and Tertiary sources

There are three types of sources that you will need to consider when evaluating where a resources originates from. You will need to determine if the source of the information is from a primary, secondary, or tertiary resource.

Primary Source: This type of information comes from the original materials or research. They are from the time period involved and have not been filtered through interpretation or evaluation. Primary sources are original materials on which other research is based. They are usually the first formal appearance of results in physical, print or electronic format. They present original thinking, report a discovery, or share new information.

Secondary Source: This type of information is harder to define than primary sources. Generally, they are accounts written after the fact with the benefit of hindsight. They are interpretations and evaluations of primary sources. Secondary sources are not evidence, but rather commentary on and discussion of evidence. However, what some define as a secondary source, others define as a tertiary source. Context is everything.

Tertiary Source: This type of information consists of a distillation and collection of primary and secondary sources. This is a compellation of knowledge gathered from many sources and then written by someone else.

The following chart displays the general type of information and resources you would use for each of these sources

Primary
Artifacts (e.g. coins, plant specimens, fossils, furniture, tools, clothing, all from the time under study); Audio recordings (e.g. radio programs) Diaries; Internet communications on email, listservs; 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); Patents; Photographs Proceedings of Meetings, conferences and symposia; Records of organizations, government agencies (e.g. annual report, treaty, constitution, government document); Speeches; Survey Research (e.g., market surveys, public opinion polls); Video recordings (e.g. television programs); Works of art, architecture, literature, and music (e.g., paintings, sculptures, musical scores, buildings, novels, poems). Web site
Secondary
Bibliographies (also considered tertiary); Biographical works; Commentaries, criticisms; Dictionaries, Encyclopedias (also considered tertiary); Histories; Journal articles (depending on the disciple can be primary); Magazine and newspaper articles (this distinction varies by discipline); Monographs, other than fiction and autobiography; Textbooks (also considered tertiary); Web site (also considered primary)
Tertiary
Almanacs; Bibliographies (also considered secondary); Chronologies; Dictionaries and Encyclopedias (also considered secondary); Directories; Fact books; Guidebooks; Indexes, abstracts, bibliographies used to locate primary and secondary sources; Manuals; Textbooks (also be secondary)

Examples of sources from Library Catalogs

Primary	diaries world war
Secondary	biography world war
Tertiary	encyclopedia world war