Different editing styles in English

Did you know there's often more than one correct way to write the same thing in English? You were taught one way, then you see it written differently somewhere else, and now you're not sure which is right. This happens to native speakers too.

English is full of rules that shift depending on context: capitalization, punctuation, spelling, how you write numbers, how you handle foreign words, how you cite sources. A lot of those choices come down to which style you're following.

Major style guides

Several style guides exist to help writers and editors apply these rules consistently. Four come up most often:

AP style (The Associated Press Stylebook): used by newspapers, magazines, and broadcast writers.

APA style (Publication Manual of the American Psychological Association): used in academic and scholarly writing, healthcare, psychology, and the natural sciences.

Chicago style (The Chicago Manual of Style): used in published books and fiction, academic journals, business, history, and the humanities.

MLA style (MLA Handbook): used in academic writing, literary criticism, and the humanities.

How style guides differ

The differences are in the details, and they're what give each style its character.

APA, Chicago, and MLA all use the Oxford comma (the serial comma), the last comma before "and" in a list. AP drops it. You can see it here:

With Oxford comma: I packed milk, chocolate, and bread.

Without: I packed milk, chocolate and bread.

For titles, Chicago and MLA lowercase short prepositions whatever their length, while AP and APA capitalize any preposition of four letters or more. Take this title:

AP and APA: A Letter With Love

Chicago and MLA: A Letter with Love

To show possession on a name ending in s, AP adds just an apostrophe. APA, MLA, and Chicago add an apostrophe plus another s. Compare:

AP: James' cat

APA, MLA, Chicago: James's cat

Citations differ too. AP cites sources in the text and skips a bibliography. APA uses an author-date format, MLA uses author-page, and Chicago offers two systems: author-date, or notes and bibliography. For instance:

APA: (Schmidt, 2024)

MLA: (Schmidt 47)

Editors don't memorize all of this. They keep the guides to hand and know where to look when a question comes up. Sometimes the guides agree, sometimes they don't.

What's even better is that you're not expected to know every style either. And it's the whole reason editors exist. Depending on what you're writing, a different set of rules applies, and an editor's job is to keep a piece consistent with the one it's meant to follow.