Chicago Citation Style was created by the University of Chicago in 1906. Chicago-style source citations come in two varieties- 1. Notes and Bibliography and 2. Author-date.
The Notes and Bibliography style is preferred by many in humanities disciplines. Citations are provided in footnotes or endnotes and are usually accompanied by a bibliography.
The Author-Date style (sometimes called "Reference List" style): sources are cited using parenthetical in-text citation and full details are provided in a reference or works cited list.