Historical sources encompass "every kind of evidence that human beings have left of their past activities — the written word and spoken word, the shape of the landscape and the material artefact, the fine arts as well as photography and film."[1]
While the range of potential historical sources has expanded to include many non-documentary sources, nevertheless "the study of history has nearly always been based squarely on what the historian can read in documents or hear from informants".[2]
Historical sources are usually divided into primary and secondary, though some historians also refer to tertiary sources.
In the study of history as an academic discipline, a "primary source" (also called an "original source") is a first hand account of events by someone who lived through them. "Primary sources were made during the historical period that is being investigated."[3]
Inscholarship, a secondary source[4][5] is a document or recording that relates or discusses information originally presented elsewhere.
A secondary source is one that gives information about a primary source. In a secondary source, the original information is selected, modified and arranged in a suitable format. Secondary sources involve generalization, analysis, interpretation, or evaluation of the original information.
Atertiary source is an index or textual consolidation of already published primary and secondary sources[6] that does not provide additional interpretations or analysis of the sources.[7][8] Some tertiary sources can be used as an aid to find key (seminal) sources, key terms, general common knowledge[9] and established mainstream science on a topic. The exact definition of tertiary varies by academic field.
