Primary Sources According to the Library of Congress, a primary source is a first-hand record of an event or topic created by a participant or a witness to that event or topic. Primary sources can be a document, letter, eye-witness account, diary, article, book, recording, statistical data, manuscript, or art object. Primary sources vary by discipline and provide an original source of information about an era or event. Although primary sources can include first-hand accounts that were documented later, such as memoirs or oral histories, primary sources created or written closest to the time of the actual event are considered to be the most useful sources for research purposes.
Use primary sources as evidence to support your research.
According to the Library of Congress, a secondary source is second-hand information written or created after an event. Secondary sources may summarize, interpret, review, or criticize existing events or works. Secondary sources were written or created after an event by people who were not at the original event. Secondary sources can be many formats including books, articles, encyclopedias, textbooks, or a scholar’s interpretation of past events or conditions.
Use secondary sources to analyze, interpret, and support your research.
A tertiary source presents summaries or condensed versions of materials, usually with references back to the primary and/or secondary sources. They can be a good place to look up facts or get a general overview of a subject, but they rarely contain original material.
Use tertiary sources at the start of your research to help find information on a new topic.
| Subjects | Primary | Secondary | Tertiary |
|---|---|---|---|
| Art | Painting | Critical review of painting | Encyclopedia article of artist |
| History | Civil War diary | Book on Civil War battle | List of Civil War battle sites |
| Literature | Novel or poem | Essay about themes in the work | Biography of author |
| Political Science | Geneva Conventrion | Article about prisoners of war | Chronology of treaties |
| Agriculture | Conference paper on tobacco genetics | Review article on the current state of tobacco research | Encyclopedia article on tabacco |
| Chemistry | Chemical patent | Book on chemical reactions | Table of related reactions |
| Physics | Einstein's correspondence | Biography on Einstein | Dictionary of relativity |
Chart created by Virginia Tech Libraries
For more examples of primary sources, check out this guide compiled by Yale University - Types and Formats: Primary Resources
According to the Society of American Archivists, archival silence describes the unintentional or purposeful absence or distortion of documentation of enduring value, resulting in gaps and inabilities to represent the past accurately.
Some basic examples may include:
However, many gaps in historical record are due to broader and more complex issues. Archives only hold historical evidence that was documented, preserved, and collected. Archival material can only be identified and put to use when it's adequately described and made accessible to the researchers who need it.
Recognizing the silences that exist within an archival collection does not mean you cannot use the collection in your research or that you need to fill every gap in the story. Acknowledging the ways our bodies of evidence are limited leads us to more informed conclusions and more accurate understandings of history, while identifying clear areas for future research.
To learn more about Archival Silence, check out this guide created by The University of Colorado - Boulder
