Primary sources enable the researcher to get as close as possible to the truth of what actually happened during an historical event or time period. "Primary source" is a term used in a number of disciplines to describe source material that is closest to the person, information, period, or idea being studied. A primary source (also called "original source") is a:
It serves as an original source of information about the topic. Similar definitions are used in library science, and other areas of scholarship. In journalism, a primary source can be a person with direct knowledge of a situation, or a document created by such a person.
Primary sources are distinguished from secondary sources, which cite, comment on, or build upon primary sources, though the distinction is not a sharp one.