A study of cultural history could include fictional sources such as novels or plays.In a broader sense primary sources also include artifacts like photographs, newsreels, coins, paintings or buildings created at the time.The National Archives and Records Administration also has digital collections in Digital Vaults.
Primary sources are distinguished from secondary sources, which cite, comment on, or build upon primary sources.
Generally, accounts written after the fact with the benefit (and possible distortions) of hindsight are secondary.
Both digitized and not digitized materials can be found through catalogs such as World Cat, the Library of Congress catalog, the National Archives catalog, and so on.
History as an academic discipline is based on primary sources, as evaluated by the community of scholars, who report their findings in books, articles and papers.
Digital copies of various classes of documents at the National Archives (including wills) are available from Documents Online.
Most of the available documents relate to England and Wales.
In scientific literature, a primary source is the original publication of a scientist's new data, results and theories.
In political history, primary sources are documents such as official reports, speeches, pamphlets, posters, or letters by participants, official election returns and eyewitness accounts.
For example, a memoir would be considered a primary source in research concerning its author or about his or her friends characterized within it, but the same memoir would be a secondary source if it were used to examine the culture in which its author lived.
"Primary" and "secondary" should be understood as relative terms, with sources categorized according to specific historical contexts and what is being studied.