Graduate researchers will engage with various types of information sources throughout the research process. In scholarly writing, information is categorized into one of three main source types: Primary, Secondary, or Tertiary.
Sources are categorized by their "distance" from the original event, data, work, etc.
| Primary Source | Secondary Source | Tertiary Source |
|---|---|---|---|
Definition | Information in its purest form - before it has been analyzed or commented on. | Information that analyzes or interprets primary sources but offers no new evidence. | Information that compiles, summarizes, or condenses primary/secondary sources on a particular topic or group of topics. |
Characteristics | Raw data, original artifacts, first-hand accounts. | Interpretation, analysis, critique, review. | Summary, broad overview, compilation (typically includes only citations) |
Uses | Personal interpretation/analysis, direct evidence, claim confirmation. | Literature review, summary of opinions, support for claims/analysis. | Topic exploration, basic research, fact-finding. |
Examples | Interviews/transcripts, speeches, diaries, birth certificates, scientific research (data), newspaper articles, original literature, artifacts, etc. | Biographies, journal articles, textbooks, commentaries, literary criticism, scientific research (findings/analysis), etc. | Encyclopedias, bibliographies, abstracts, indexes, catalogs, dictionaries, literature reviews, etc. |
Each type of source has its place in academic research. Typically, researchers first interact with a topic through tertiary sources then explore secondary and primary sources as they dig deeper into their research. The appropriateness of each type of source for academic use varies widely by the nature and topic of the research, with each serving a unique function.


