Many people have heard the phrase “Oxford Comma” and have no idea what it means. Even some of those who do know aren’t sure why anyone would care.
When you’re writing in a programming language, you use the conventions of that language to communicate what you want the program to accomplish. When you use one character (;) instead of another (:), it makes a difference in the command. Or if you leave out the character altogether, it makes the command totally different. You have to make certain that the command you’re writing is exactly what you want the computer to do. Otherwise, the computer will do something you didn’t intend, which is not a good thing.
It is the same with punctuation when you’re writing in English. While a person might be able to understand what you meant, they may not understand because of what is implied. It makes it easier all around when the punctuation is correct. A popular example is the difference between these two statements:
“Let’s eat Grandma!”
“Let’s eat, Grandma!”
This is why commas (and punctuation, in general) matter. You’re hungry no matter which sentence you use, but what is on the menu differs greatly.
The Oxford Comma is no different. It’s a way to make your sentences easier to understand. The definition of the Oxford Comma is that it is the last comma in a list—not a bulleted list, but a list that is written into a sentence.
Here’s an example of a sentence without the Oxford Comma:
“We had pumpkin, apple and lemon meringue pies.” (How many pies were there?)
And here’s the same sentence, with the Oxford Comma:
“We had pumpkin, apple, and lemon meringue pies.” (Oh – there were three pies!)
These sentences mostly make sense either way. The Oxford Comma doesn’t matter as much, because the topics are not life-altering in importance. However, the following is an example in which the Oxford Comma does matter:
“We invited the drag queens, JFK, and Stalin.” (3 groups – big, fun party!)
“We invited the drag queens, JFK and Stalin.” (only 2 people – small, scary party!)
In this case, the sentence with the Oxford Comma is much more preferable than the one without it. We’re not talking about pies here – we’re talking about people and ideas that matter.
There’s an argument among English scholars as to whether or not that comma is necessary to help with the communication. Many people don’t care about commas, and therefore think it’s a silly argument. However, unless you really mean to have JFK and Stalin dress in drag, it is a rather important part of the sentence.
Some companies have a standard regarding the Oxford Comma. When the company does not have a standard, then the department / project makes the standard. Whatever the decision, whenever you write something that the customer might see, it’s best to remember the standard that was set and stick to it. Don’t mix and match the commas; it has the potential to look unprofessional. Some customers may not notice details like punctuation. Other customers will notice those details. The ones who do notice the punctuation of a document might not say anything to you. Instead, they might take their business elsewhere.
Now you are familiar with the Oxford Comma, and can make an informed decision about whether or not to use it.