Primary sources are the evidence of history, original records or objects created by participants or observers at the time historical events occurred or even well after events, as in memoirs and oral histories. Primary sources may include but are not limited to: letters, manuscripts, diaries, journals, newspapers, maps, speeches, interviews, documents produced by government agencies, photographs, audio or video recordings, born-digital items (e.g. emails), research data, and objects or artifacts (such as works of art or ancient roads, buildings, tools, and weapons). These sources serve as the raw materials historians use to interpret and analyze the past.
Reference and User Services Association, a division of the American Library Association (http://www.ala.org/rusa/sections/history/resources/primarysources)