Professors in history and some humanities professors require footnotes based on "The Chicago Manual of Style." In this style, you will place the reference number in superscript after the sentence that contains the referenced material or quote. For example: A mass of homeless and unemployed men drifted across the American landscape, looking for work or a handout wherever they could find it.3 Material in this sentence was borrowed from Tom Brokaw's book "The Greatest Generation." The footnote would annotate as: 3Tom Brokaw. The Greatest Generation. (New York: Random House, 1998). 4-5.
In most English classes, you will use the Modern Language Association (MLA) guidelines for formatting your paper. Those who use the MLA system of parenthetical documentation have the option of using information footnotes for one of two purposes. The first is to provide material that might interrupt the flow of the paper and yet is important enough to be included. The second reason is to refer the reader to any sources not discussed in the paper. For example, 1 For a complete discussion of the requirements of registering a car in Mexico, see Mexico Guide 9.
When writing in the social sciences, the American Psychological Association (APA) style is normally used to cite sources. According to the Perdue Online Writing Lab, "APA does not recommend the use of footnotes and endnotes, because they are often expensive for publishers to reproduce." If you decide that explanatory notes are necessary to your paper, the APA style permits the use of two types of footnotes: content and copyright. Content Notes provide supplemental information to your readers and is written like the MLA footnote. Copyright notes begin the citation with "Note." For example, Note. From "Title of the article," by J. Smith and R. Jones, 2010, Journal of Medicine, 11, p. 111. Copyright 2010 by Copyright Holder. Reprinted with permission.