Why We Use MLA APA and Chicago Citation Styles and Not Just One
Research papers typically include citations at the end and even in the body of the text--and there is not just one way to include this information. MLA, APA and Chicago are the three primary styles used in academia, and your choice of which one to use for citation listings will vary depending on the academic discipline. Clarify with your professor how she wants you to cite your references and follow the appropriate style guide to ensure you appropriately document your research.
Humanities disciplines commonly use MLA Style, which includes both in-text citations and a "works cited" list at the end of the paper. With in-text citations, the author offers some information about the source immediately after the quotation and includes a complete listing in the works cited list. The humanities tend to focus on comparing and contrasting the works of different authors and how their writings influence one another; therefore, MLA citations emphasize the author's name and the page number of the quotation in the original text, helping scholars to locate the information easily for further review.
Like MLA, APA Style uses in-text citations as well as a listing at the end, called simply "references." You'll find APA primarily in the social sciences, which favor APA's emphasis on the year that a source was published. Although the author's name is also important in APA, the year tells readers how current the information is and how the research has evolved over time.
Chicago Style permits writers to use either footnotes at the bottom of pages or in-text citations. It also allows writers to focus on either the page number or the year of publication in citations, depending on the intended purpose of the quotation or research. Historical research benefits from Chicago Style's use of footnotes, enabling writers to avoid lengthy parenthetical information that could distract from the evidence at hand. Instead, readers can focus on the text and consult the footnotes if they want to seek out further information. Chicago Style also calls for a listing of citations at the end, known as a bibliography.
In all three styles, writers can use discursive endnotes to convey additional information about a piece of evidence. These notes will be typically a sentence or two of information that supports the evidence but is not part of the paper's main argument. Some Chicago Style papers will mix discursive endnotes with those that include only bibliographical information.
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