A citation (or reference) is bibliographic data (title, author, etc.) about a document organized in an academically preferred or standardized format (citation style). The bibliographic data of the source (document) is collected for referential or evidential purposes.
Modern software programs can cite or arrange bibliographic data via automated processes, removing the need to do so by direct input. A software program that generates or organizes bibliographic data according to preferred citation style is called a citation reference manager.
Citation Style is determined by the type or subject of a paper, journal or publication preference, workplace or institutional standards, etc. For example: in the biomedical sciences, the APA and Vancouver styles are preferred. In the Humanities, the MLA style is preferred.
Citation Styles focus on in-text citations and reference and bibliography lists. They may also focus on manuscript formatting and structuring, over all. This will include guidelines such as presenting evidence, statistics, charts, etc.
APA is an acronym for the American Psychological Association.
APA Style originated in 1929. Its rules and guidelines--designed for clarity of identifying information and ease of access to information--are cataloged in Publication Manual of the American Psychological Association, a frequently updated guidebook used by students, professionals and editors alike.
Preferred by the Humanities, there are two types of references used in The Chicago Style Guide: Notes and Bibliography AND Author-Date.
1. Zadie Smith, Swing Time (New York: Penguin Press, 2016), 315–16.
2. Brian Grazer and Charles Fishman, A Curious Mind: The Secret to a Bigger Life (New York: Simon & Schuster, 2015), 12.
EXAMPLE: Book Citation (in bibliographic list according to alphabetical order)
For more on the Chicago Style: https://www.chicagomanualofstyle.org/tools_citationguide.html
The Council of Science Editors (CSE), formerly known as the Council of Biology Editors (CBE), use in-text citations in the name-year format. The bibliography lists the sources alphabetically at the end of the research paper.
Here is an example of the name-year format:
(McMillan et al., 2008).
The Modern Language Association (MLA) is the most common formatting style. It is preferred standard for the Humanities and social sciences.
In-text citation follows the author-page format.
Burke, Kenneth. Language as Symbolic Action: Essays on Life, Literature, and Method. University of California Press, 1966. (Book with single author)
Nordhaus, William D. "After Kyoto: Alternative Mechanisms to Control Global Warming." American Economics Review, vol. 96, no. 2, 2006, pp. 31-34. (Journal)
The Vancouver Style is formally known as Recommendations for the Conduct, Reporting, Editing and Publication of Scholarly Work in Medical Journals (ICMJE Recommendations). It was developed in Vancouver in 1978 by editors of medical journals and well over 1,000 medical journals (including ICMJE members BMJ, CMAJ, JAMA & NEJM) use this style.