What is the Oxford Comma & Should You Use It?

Let's start with a disclaimer - I am an Oxford comma user. I love it, need it, insist that my students use it. Please feel all the Oxford comma support emanating from this corner of the internet.

Recently, I started wondering why so many consider this absolutely crucial punctuation mark optional. Why is there no steadfast rule demanding we all use it?

Let's find out where it came from, why some people don't use it, and whether you should.

What Is The Oxford Comma?

The Oxford comma is the last comma in any sentence that lists three or more things. It typically comes before the conjunction, which is a connecting word in a sentence, such as and, but, or if.

My favorite things about the beach are the sun, sand, and water.

The Oxford comma comes right after sand.

What Is The Serial Comma?

The serial comma is another name for the Oxford comma. You can use either. People also sometimes refer to it as the Harvard comma, but that's less common.

Most people call it the Oxford comma because Oxford University Press workers have recommended its use since the early twentieth century. Peter Sutcliffe coined the term in his 1978 book, The Oxford University Press: An Informal History.

Where Did The Oxford Comma Come From?

The Oxford comma appears to have originated in Italian writing during the 1500s. Since then, it's been used sporadically throughout the writing world.

In 1905, Horace Hart's Rules for Compositors and Readers listed the Oxford comma as a grammatical necessity. The Oxford University Press used this book as a style guide, ensuring its followers would continue to use the Oxford comma in their work.

Why Is The Oxford Comma Optional?

The Oxford comma is considered optional because not all style guides recommend it. Depending on which you follow, you may or may not use the punctuation mark in your sentence.

Typically, academics and technical writers use the Oxford comma, while journalists may not.

Which Style Guides Recommend The Oxford Comma?

The following style guides require writers to use the Oxford comma:

Oxford University Press and Harvard University Press
Modern Language Association (MLA)
American Psychological Association (APA)
The Chicago Manual of Style (aka Turabian)
Strunk & White's Manual of Style
The US Government Printing Office Style Manual
Institute of Electrical and Electronics Engineers (IEEE)
Modern Humanities Research Association (MHRA)

Which Style Guides Do Not Recommend the Oxford Comma?

The following style guides do not require writers to use the Oxford comma:

Associated Press (AP)
Cambridge University Press
The Economist
The Guardian
New York Times
The Times

Should You Use the Oxford Comma?

Well, like I said in the intro to this post, I very much think you should! Why? One word: clarity.

The Oxford comma provides clarity in your writing.

That being said, if you are bound to a style guide that asks you not to use it, you should listen or risk the wrath of your editors.

How Does The Oxford Comma Provide Clarity?

The Oxford comma clarifies meaning for the reader. The easiest way to explain this is with an example.

The most important influences in my life are my children, William Shakespeare and Ernest Hemingway.

The most important influences in my life are my children, William Shakespeare, and Ernest Hemingway.

In the first version, without the Oxford comma, it reads as though William Shakespeare and Ernest Hemingway are the writer's children.

In the second version, with the Oxford comma, it is clear that William Shakespeare and Ernest Hemingway are important influences in the writer's life. They are listed alongside their children, not as their children.

See why it's important?

Understanding the role of the Oxford comma in providing clarity helps us understand why it is required in academic or technical writing. Such misunderstandings can undermine the value of a research piece or other work that relies on reader comprehension of complicated topics.

The Takeaway

Some style guides require the Oxford comma while others do not, and you should follow whichever you are formally bound to. However, when writing outside of a style guide, the Oxford comma provides clarity to your readers.

Use it, please! :)

Links to Learn More About the Oxford Comma

Want to learn more? Here are the links I read through for this feature:

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