Primary vs. Secondary Sources — Definition, Differences, and Examples
Primary and secondary sources
Primary and secondary sources include books, articles, websites, speeches, newspapers, etc. Primary source materials are firsthand accounts. Secondary sources summarize, describe, analyze, interpret, synthesize, or evaluate primary sources. Academic and original research projects often use both types of sources.
What is a primary source?
Primary sources are original materials that come directly from an individual who witnessed an event or period. Primary sources provide the most direct evidence and insight into what occurred because people created the original documents, images, or artifacts contemporaneously or soon after the historical event depicted.
Primary sources often take the form of letters, photographs, novels, and patents:
| Field of Study | Types of Sources |
|---|---|
| History | • Diaries/Journals
• Letters • Photographs • Video Footage • Newspaper Articles |
| Art | • Paintings
• Sculptures • Photographs |
| Literature | • Novels
• Poems • Plays • Autobiographies |
| Law | • Affidavits of Petition
• Statutes • Cases |
| Science | • Technical Reports
• Laboratory Notes • Patents |
| Government | • Public Records
• Censuses • Bills/Amendments • Government Documents |
What is a secondary source?
Secondary sources summarize, analyze, or interpret primary sources and are typically written after the period identified in the primary source. Secondary sources often use primary sources to support a specific argument or persuade readers to hold a certain viewpoint.
Secondary sources often take the form of the following:
Encyclopedias
Textbooks
Political Analyses/Commentaries
Editorials
Literature Reviews/Book Reviews
Biographies
Law Reviews
Scholarly Journal Articles/Scholarly Books
Dictionaries
Research Papers/Dissertations
How to identify a primary and secondary source
To determine whether something is a primary or secondary source, consider the following questions:
| Primary Source | Secondary Source |
|---|---|
| The source was written or created by someone directly involved in the events/period. | The source was written by someone not directly involved in the events/period. |
| The source is a firsthand account and provides original information. | The source provides a response, critique, or evaluation of other materials. |
| Words that often indicate a primary source include examined, predicted, experimented, investigated, and explored. | Words that often indicate a secondary source include analysis, synthesis, overview, evaluation, and critique. |
Primary and secondary source examples
The following chart identifies specific primary sources:
| Field of Study | Primary Sources |
|---|---|
| History | • The Autobiography of Benjamin Franklin
• National Archives • Smithsonian Museums |
| Art | • Mona Lisa by Leonardo da Vinci
• The Thinker by Auguste Rodin • V-J Day in Times Square by Alfred Eisenstaedt |
| Literature | • To Kill a Mockingbird by Harper Lee
• "Mending Wall" by Robert Frost • Hamlet by William Shakespeare |
| Law | • Brown v. Board of Education |
| Science | • On the Origin of Species by Charles Darwin
• The Philosophy of Nature by Sir Isaac Newton |
| Government | • The Declaration of Independence
• The Constitution • The Bill of Rights |
The following list identifies specific examples of secondary sources:
Encyclopedia: Encyclopedia Britannica
Social Sciences Textbook: World History: Voices and Perspectives
Literary Criticism: How to Read Literature Like a Professor
Biography: Steve Jobs: The Man Who Thought Different
Legal Commentary: A Practical Guide to Legal Research