With the advent of the Internet, some original research is being shared via list serves, electronic journals, databases of scholarship, etc. In the humanities, primary sources also take the form of philosophical treatises, paintings, poems, cinema, literature, programs on electronic mass media, photographs, songs, and multimedia presentations. In history-related disciplines, primary sources are usually those that are written, recorded, photographed, or filmed within, or close to, an event. They often take the form of correspondence, diaries, personal journals, autobiographies, census records, newspaper articles, memos, and blueprints. Secondary Sources Secondary sources are those in which an original work is explained, analyzed, critiqued, summarized, interpreted, put into a context, or somehow restructured.
Secondary sources can include many of the forms taken by primary sources.
Tertiary Sources Tertiary sources are the finding tools that provide access to primary and secondary sources. These tools are frequently located in or accessed via libraries and research centers. For example, a television news program could be the object of critical analysis, in which case it would be a primary source. In another situation, the Presidential speech could also be a secondary source if the content of the President's communication were a summation of a bill passed by Congress.