A diary is a record (originally in handwritten format) with discrete entries arranged by date reporting on what has happened over the course of a day or other period. A personal diary may include a persons experiences, and/or thoughts or feelings, including comment on current events outside the writers direct experience. Someone who keeps a diary is known as a diarist. Diaries undertaken for institutional purposes play a role in many aspects of human civilization, including government records, business ledgers and military records.