Primary sources are those created at the same or nearly the same time as the occurrence of an event. In the case of oral histories, primary sources can be produced by participants in events. Primary resources include such items as correspondence and letters, diaries, memoirs, interviews, manuscripts, newspapers, government documents, treaties, statistics, speeches, oral histories, and artifacts.
Secondary sources are based on primary sources and interpret or analyze an historical event. Examples of secondary sources are books, journal and magazine articles, or reference works like dictionaries and encyclopedias.
Several good links to more information about primary sources are the following: