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ENGL 101 English Composition I: Primary/Secondary Sources

Primary, Secondary & Tertiary Sources

As you conduct research, you will consult different sources of information. An instructor may request primary, secondary, or tertiary sources. What does that mean?

Primary sources

Primary sources are original materials. 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.

Note: The definition of a primary source may vary depending upon the discipline or context.

Examples include:

  • 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 sources

Secondary sources are less easily defined 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.

Note: The definition of a secondary source may vary depending upon the discipline or context.

Examples include:

  • 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 sources

Tertiary sources consist of information which is a distillation and collection of primary and secondary sources.

  • 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 considered secondary).

Comparison across the disciplines

SUBJECT PRIMARY SECONDARY TERTIARY
Art and Architecture Painting by Manet Article critiquing art piece ArtStor database
Chemistry/Life Sciences Einstein's diary Monograph on Einstein's life Dictionary on Theory of Relativity
Engineering/Physical Sciences Patent NTIS database Manual on using invention
Humanities Letters by Martin Luther King Web site on King's writings Encyclopedia on Civil Rights Movement
Social Sciences Notes taken by clinical psychologist Magazine article about the psychological condition Textbook on clinical psychology
Performing Arts Movie filmed in 1942 Biography of the director Guide to the movie

Primary vs. Secondary Sources

Primary, Secondary, & Tertiary Sources

Simplified Summary

Primary Sources

A primary source is a document or physical object which was written or created during the time under study. These sources were present during an experience or time period and offer an inside view of a particular event. They may also present original thinking, new discoveries or new information collected at the time of an event.

Types of primary sources:

  • Original documents (including excerpts and translations): diaries, speeches, manuscripts, letters, interviews, technical reports, empirical studies (research based on scientific and experimental results), news film footage, autobiographies, official records, ancient literature, magazine and newspaper articles, public opinion polls, medical charts.
  • Creative works: poetry, drama, novels, printed music, sound recordings, art.
  • Relics or artifacts: pottery, furniture, clothing, buildings. 

Examples of primary sources:

  • Diary of Anne Frank
  • The Constitution of Canada
  • Newspaper article from the time an event occurred
  • A journal article reporting new research or findings
  • Weavings and pottery
  • Plato's Republic 

Secondary Sources

A secondary source interprets and analyzes primary sources. These sources are one or more steps removed from the event. Secondary sources may have pictures, quotes or graphics of primary sources in them.

Types of secondary sources:

  • Publications: Textbooks, magazine articles, histories, criticisms, commentaries, encyclopedias

Examples of secondary sources:

  • A journal/magazine article which interprets or reviews previous findings
  • A history textbook
  • A book about the effects of WWII

Tertiary Sources

A tertiary source is a compilation or digest of primary and secondary sources.

Types of tertiary sources:

  • Dictionaries
  • Encyclopedias
  • Bibliographies
  • Databases
  • Guidebooks
  • Almanacs