Primary source is a term use in a number of disciplines. In historiography, it is a document, recording or other source of information that was created at roughly the time being studied, by an authoritative source, usually one with direct personal knowledge of the events being described. Similar (but not identical) definitions are used in library science, and other areas of scholarship. A primary source could be a first-handed source from the past including diaries or artifacts. Primary sources have been described as those sources closest to the origin of the information or idea under study. Primary sources have been said to provide researchers with "direct, unmediated information about the object of study." They may contain original research or new information not previously published elsewhere. They have been distinguished from secondary sources, which often cite, comment on, or build upon primary sources. They serve as an original source of information or new ideas about the topic. Primary and secondary, however, are relative terms, and any given source may be classified as primary or secondary, depending on how it is used.