If you hang out with editors and armchair grammarians, you soon learn that the serial comma is a contested issue.

You will hear some defend to the death their right not to use it, while others insist that every time it’s omitted the English language teeters closer to the brink of collapse.

If you hang out with editors and armchair grammarians or count them among your Facebook friends, it’s best to keep Sturgis’s Law #16 in mind. In the annotation of Sturgis’s Laws I haven’t got there yet , but here’s a sneak preview:

The amount of discussion devoted to an issue is inversely proportional to the issue’s importance and to the preparation required to say anything meaningful about it.

So what exactly is this little mite that inspires such passion?

The serial comma is also called the Oxford comma, but I prefer “serial,” and not just because I live on the left side of the Atlantic. The serial comma, after all, is about how one punctuates series of three or more items, specifically about whether one should use a comma before the conjunction that precedes the last element.

This sentence is widely circulated by serial-comma fans to prove their point: “I’d like to thank my parents, Ayn Rand and God.” You’ve probably seen it, or one very like it.

Without the serial comma, “Ayn Rand and God” could be an appositive phrase. Is the writer really saying that Ayn Rand and God are his/her parents? Ha ha ha.

As an argument for the serial comma, however, this example is less than persuasive. Take any sentence out of context and myriad misreadings become possible. The Associated Press style guide, widely used by newspapers and businesses across the U.S., generally doesn’t recommend the serial comma unless confusion might result from its absence. The sky hasn’t fallen in yet, and besides, if one fears confusion might result from “my parents, Ayn Rand and God,” one is free to insert a comma after “Rand.”

That said, I’m a serial-comma fan. This has as much to do with habit as anything else. I don’t recall anyone making a big deal about serial commas when I was in school, but when I was an apprentice editor in the very late 1970s, “Chicago style” — currently codified in The Chicago Manual of Style, 16th edition — was drummed into my head. Chicago recommends the serial comma, as do most U.S. publishers.

As a result, I’m used to it. I notice when it’s not there. Here’s a sentence chosen at random from my novel in progress. The speaker is referring to Moshup, the giant of Wampanoag legend.

“He caught whales one-handed, cooked them up here, and shared the meat with the resident Wampanoags.”

To my eye and ear, the comma after “here” makes clear that there are three elements here, not two. If that comma isn’t there, my eye slides to the end of the sentence without registering the slight break that separates the third element from the second. A reader who doesn’t expect a comma there probably isn’t going to miss it.

Sometimes, however, I want my eye to slide to the end of a phrase. The U.S. flag is often called “the Red, White and Blue.” We say it almost as if it’s one word: “the RedWhiteandBlue.” With a comma after “White” I visualize three distinct colors, not a single flag. If I wrote “The flag is red, white, and blue,” would I use the serial comma? Yes, I would. (I just did.)

The serial comma is rarely used, by the way, when the conjunction “and” is represented by an ampersand: “The flag is red, white & blue.” Ampersands are rarely used in formal or even informal writing, so this comes up more often in display type, like advertisements, posters, and headlines. Why is this? Damned if I know, but the big ampersand dwarfs the tiny comma so I don’t blame the comma for wanting outta there.

But it’s more than habit and long experience that makes me a serial-comma fan. Because I generally use it, I can use its omission to shape the meaning of a phrase. Here’s a simple example:

Gathered in the foyer were colleagues, writers, and editors she’d known for years.

“Colleagues, writers, and editors” are three distinct groups, right? Now remove the commas after “writers”:

Gathered in the foyer were colleagues, writers and editors she’d known for years.

“Writers and editors” is now in apposition to “colleagues.” In other words, the writers and editors are her colleagues.

To a non-serial-comma user the second sentence could go either way: two groups or three? The astute non-serial-comma user might insert a serial comma here if three groups were meant, realizing that this is an instance where the serial comma serves a purpose. With any luck the non-serial-comma-using copyeditor would realize as much and not delete it.

So I use the serial comma regularly because if I do, its omission becomes a tool in my toolkit. Even if I only use it a few times a month, I like knowing it’s there.