Primary or Secondary
Historians use two principal kinds of materials: primary sources and secondary sources.
Primary sources:
Primary sources are materials that serve as original evidence documenting a time period, an event, a work, people, or ideas. Examples include: newspaper articles, government documents, diaries, works of literature, photographs, oral histories, and more.
Secondary sources:
Secondary sources are information sources that provide interpretation, analysis, or commentary based on primary sources in order to provide understanding of a topic. For history, the two most common types of primary sources are scholarly books (monographs) and peer-reviewed articles.
Background information:
Another type of source, sometimes called a tertiary source, is background information. Background information like encyclopedia articles can help you understand the context of a subject, but they are not typically materials to base your research papers on.
