The Chicago style (or Chicago Manual of Style, CMOS) is another widely used system for formatting and citing sources in academic and professional writing. It’s published by the University of Chicago Press and is especially common in history, literature, and the arts, though it’s also used in other disciplines.

It offers two main citation systems:

1. Notes and Bibliography (NB) System

* Common in the humanities (history, religion, literature, etc.).
* Uses footnotes or endnotes for citations, plus a bibliography at the end.
* Example:

• In-text (footnote):
• > ¹ John Smith, History of Modern Europe (New York: Academic Press, 2020), 45.
• Bibliography entry:
• > Smith, John. History of Modern Europe. New York: Academic Press, 2020.

2. Author–Date System

* Common in the sciences and social sciences.
* Uses parenthetical in-text citations (like APA), with a reference list at the end.
* Example:

• In-text: (Smith 2020, 45)
• Reference list:
• > Smith, John. 2020. *History of Modern Europe.* New York: Academic Press.

3. Paper Formatting

* Similar to APA: standard letter-size paper, 1-inch margins, readable fonts.
* Title page is often used.
* Footnotes appear at the bottom of the page; endnotes appear at the end of the text before the bibliography.

Key difference from APA:
Chicago gives you the choice of using footnotes/endnotes (with full details) or the author-date citation system, depending on your discipline. APA, by contrast, always uses author-date.