The Chicago Manual of Style has two systems, Notes and Bibliography and Author-Date.
Notes and Bibliography uses footnotes, and is most frequently used in the humanities and the arts. Author-Date is mostly used in the social sciences. Both systems use the same citation format, but only Notes and Bibliography uses footnotes.
Notes and Bibliography is commonly used in humanities and history, and is the only current citation style that fully accommodates and provides rules for footnotes/endnotes. Consider using the Notes and Bibliography system for any paper where footnotes/endnotes are required or if you need to document:
Notes and Bibliography also allows authors to maintain a flow within main body of a text while at the same time providing convenient locations for:
Chicago Author-Date style is a parenthetical style like APA, and is commonly used in anthropology, politics, economics, and other social science disciplines.
Official quick guides for basic citation questions, including both parenthetical and footnote citations: