Do you employ a serial comma — the final comma in a sentence such as “I bought one apple, two bananas, and three oranges”?
If your work for or with a business or organization involves publishing content in print or online, that decision has been made (or should have been made) for you in a style guide, a manual to be followed in production of all the content published by that business or organization. If you determine a business or organization’s style, or you self-publish in print or online, the decision is up to you.
In most journalistic print and online publications and in much other online content, the serial comma is omitted. (This omission is also common in British English.) However, in most books and in many other publications published in the United States, it is required.
I strongly favor the serial comma. Why?
In a sentence such as “I bought one apple, two bananas and three oranges,” no ambiguity exists. But in “I ordered ham and eggs, toast and jam and pie and ice cream,” the cavalcade of conjunctions gets confusing, and in contexts in which it’s not as clear which list items might be distinct and which might be linked, the absence of the final comma might require readers to reread the sentence to establish the organization. So, the solution in this case is to use a serial comma when confusion could arise.
That means that no-serial-comma publications will print or post “I bought one apple, two bananas and three oranges” but “I ordered ham and eggs, toast and jam, and pie and ice cream.” The resulting obvious question is why not, for the sake of consistency, just insert a serial comma in all cases?
Another complication is illustrated in this well-known hypothetical statement: “I dedicate this book to my parents, Ayn Rand and God.” Without the serial comma, the statement could be read as acknowledging four entities: two parents, an author, and a deity. But it could also refer to two parents, one of whom is an author and other of whom is a deity. Again, the presence of the serial comma eliminates the ambiguity.
This issue may seem trivial, but the English language is constructed of myriad trivialities that combine into an imperfect system but one that has supported the world’s predominant language. (Yes, twice as many people speak Mandarin as English, but my reference point is global significance.)
Commas are an abundant resource, and you can pull any ordinary one out of your comma bucket to serve as a serial comma.