Tertiary source
A reference work that collects, organizes, or summarizes information drawn from primary and secondary sources, such as an encyclopedia or index.
Primary source: A source created by a participant, witness, or institution directly involved in the events or subject it documents. Tertiary works often trace their information back to these original records.
Encyclopedia: A reference work presenting organized articles about a broad range of subjects or a specialized field. Encyclopedias are a familiar form of tertiary source that summarizes established knowledge.
Original research: Research that produces new data, observations, or analysis rather than only synthesizing existing work. Unlike tertiary summaries, original research contributes findings to the source record.
Source criticism: The examination of a source's origin, context, reliability, and evidential value. Tracing a tertiary claim to its sources helps assess what the summary leaves out.
Secondary source: A source that analyzes, interprets, or synthesizes primary evidence. Tertiary works commonly condense findings first developed in secondary sources.
Index (publishing): An ordered guide to topics, names, or terms and the locations where they appear in a publication or collection. Indexes point to relevant material without requiring a narrative account of the subject.
Literature review: A structured synthesis and evaluation of existing research on a defined question or topic. Literature reviews analyze a research field in depth, unlike broad reference compilations.
Information literacy: The ability to find, evaluate, interpret, and use information effectively. Using reference works responsibly requires judging their scope and checking their supporting sources.
Bibliography: A systematically arranged list of works cited, consulted, or recommended. Bibliographies make the sources behind a tertiary work easier to identify.
Abstracting and indexing service: A service that summarizes and organizes publications to support searching and discovery. These services turn many separate publications into searchable records and summaries.