Primary sources are evidence of events, people, history, or objects created by participants or observers at the time or during the time period that these events occurred, people lived, or objects were created. Some primary sources are created "after the fact" and recorded as memoirs, narratives, and oral histories. Whether written at the time or recorded later, primary sources are considered to be direct or first-hand evidence of historical facts.
Some examples of primary sources are:
Primary sources are the basis of most historical research. Their accessibility and preservation are critical to historical research.
Secondary sources draw upon primary sources in order to create additional knowledge. Secondary sources may analyze, critique, evaluate, expand, interpret, and synthesize information from primary sources, often referring to specific aspects of the primary source. Contrary to primary sources, secondary sources are created at a time or during a time period after the event has occurred, and without direct observation or first-hand knowledge of any kind.
Some examples of secondary sources are:
Historical research often incorporates the use of secondary sources in combination with primary sources to synthesize information and create additional historical knowledge. This is essentially what occurs when students conduct research and write a term paper for a history course.