Style Guides & Manuals: What Are They?

Perhaps your high school English teacher told you about style guides, but maybe you didn’t even come across them until college when your English Composition instructor informed you, “You must use MLA style or fail this course.” I have said it, and other instructors have insisted on APA or Chicago (Turabian) Style as the style guide that that particular university department dictates. Or, if you are a middle-aged or older person, you were likely told to use the old stand-by The Elements of Style.

Style guides, which become style manuals if they’re lengthy enough, tell writers how to use punctuation, which words to capitalize, how to cite sources, how to format a list, how to quote others’ writing, how to abbreviate certain words, when to italicize or underline words, and more. The style manual giants are the American Psychological Association (APA), the Modern Language Association (MLA), the Associated Press (AP), and The Chicago Manual of Style. And, of course, there’s the little book called The Elements of Style, which is not used much anymore but has withstood the test of time. Institutions that put out great amounts of writing, such as newspapers, magazines, and major websites, often have their own style guide.

Why are there so many? Each has its own reason—its own mission—that it wants to achieve with its published words. Here are the missions of the major ones:

  • Associated Press (AP) StyleBook:  “to be clear and concise and understandable around the globe, no matter what the news is or where it happens.” Often cited as “the bible for journalists,” its ways of using words are aimed at news readers, so they often suggest avoiding punctuation that other style guides insist upon. News writers want to save space, so their purpose is to use as few characters and spaces as possible while still getting the point across. One of the most debated issues is the “Oxford comma,” which I will address later on.
  • Modern Language Association (MLA) Style Manual: Although I couldn’t locate a mission statement for the Manual itself, the MLA’s mission on is to “promot[e] the study and teaching of languages and literatures through its programs, publications, annual conventions, and advocacy work.”  Because it is focused on the scholarly field of English and other languages, it is probably the highest authority in the United States on the use of English. The style manual of choice for most college and university English departments, it focuses on using words in the clearest ways, punctuation that adds clarity, citing research sources, and usage issues. It is predominant in the fields of literature, language, writing studies, screen arts, digital humanities, pedagogy, and library studies.
  • American Psychological Association (APA) Style Rules:  This style guide is available in a few different formats, which can be viewed at My understanding of their mission is that it wants, in its published college papers, books, journal articles, etc., to make prominent who the author is and when the piece was published. As you can imagine, results of research cited from 1954 aren’t going to have as much impact as those completed within the last year, so APA’s source documentation highlights the date.

Here’s a (fictitious) book citation example:

Jones, W. (2017) The Success of the Gottman Method of Marriage Counseling. APA Journal. Iowa: University of Iowa Press.

And within the text of the publication, the citation would be this: (Jones, 2017). In both cases the date stands out.

  • The Chicago Manual of Style: First published in 1906, the manual was initially quite short, is now over 1,000 pages long, and is mainly used by the writing and publishing industries. It is sometimes called the Turabian style because the author of the first edition, published by the University of Chicago Press, was Kate L. Turabian. It is said to have mainly the writer in mind because it contains details about editing, proof-reading, titling, and even spacing that is crucial in the journalism world. It is considered less academic than MLA and APA.

Here are just three examples of some differences in usage:

Oxford Comma

MLA, APA, and Chicago all agree that when a series of items is presented, there should be a comma between all items including the last two because omitting this last one can lead to ambiguity. AP does not agree with this and wants that last one left out for the sake of saving space. Here’s an example:

Without the Oxford comma:  I like cooking my family and my pets.

With it:  I like cooking, my family, and my pets.

It seems to me that most grammarians prefer the Oxford Comma because it reduces ambiguity. To leave it out just for the sake of a little extra space does not make sense to me.


MLA, APA, and Chicago all agree on how to create an ellipsis (3 periods in a row) to indicate deleted material from a quotation, although it’s used in casual writing sometimes to indicate that something more to come is implied rather than spelled out. Here’s an example:

MLA, APA, Chicago: Johnson reports that he “gave no credibility . . . to the methodology.”

AP: Johnson reports that he “gave no credibility … to the methodology.”

As you can see, the academic style guides want “spaced” periods whereas AP wants to save those spaces.

Highlighting titles of other publications

MLA, APA, and Chicago all want titles of minor works—for example, articles, songs, and poem titles—enclosed in quotation marks and major works such as books, newspaper names, movies, and journals all in italics.

AP wants just the major words capitalized and titles of all works enclosed in quotation marks with no italics. Some other style books dictate neither italics nor quotation marks.

To really know any one of these fully, you most likely have to purchase the manual, although Purdue University’s Online Writing Lab (OWL) is a great online source, and others are also available on the Internet.

No doubt, it is easier to learn and retain the rules of just one of these style guides. I always felt sorry for my Comp students who were taking English Composition, Psychology, and History (which prefers Chicago style) all in the same semester. If they were also going into journalism and taking a course within that department, then they also had to use AP, so four different styles all in one semester. Pretty crazy, eh?

One handy manual is Diana Hacker’s A Pocket Style Manual because she details the requirements of three of these four: MLA, APA, and Chicago but not AP. You can likely purchase a used copy online for about three bucks.

Happy writing!

Susan is a retired English professor of 25 years who enjoys all that her home state of Colorado offers. She is an avid road bicyclist, hiker, and viola player with six published books who has really, really—yes really—enjoyed teaching grammar and mechanics to her students.