Say you're helping plan a friend's party,

and he sends you a text

asking you to "bring Bob, a DJ and a clown."

You're pretty impressed.

You had no idea Bob was so multitalented.

But when the day arrives,

it turns out that he's not,

and you were supposed to bring three different people.

As you and Bob sit at the silent, clownless party,

it occurs to you that the confusion could've been avoided

simply by using another comma after DJ.

This final comma in a list,

placed directly before the main conjunction,

such as and, or, or nor,

is called the serial comma,

or Oxford comma.

And it has long driven grammar nerds crazy

because even major language institutions

can't agree on whether it should be used.

Ironically, the Oxford comma

is more common in the United States,

where it's recommended by

the MLA, the Chicago Style Manual,

and the US Government Printing Office,

though not by the AP Style Book.

In the UK and other English-speaking countries,

most style guides do not support the comma's use,

with the exception of its namesake,

the Oxford University Press.

Why not use the serial comma?

One of the main arguments

is that the conjunction is usually enough

to denote a separate entity.

And where it's not,

like in your ill-fated invite list,

changing the order of terms will usually do the job.

Journalists also dislike the comma

because it takes up precious space

and can make text look cluttered.

Sometimes, it can even create confusion of its own.

For example,

if your friend had asked for "Bob,

a DJ and a puppy,"

you'd probably figure out

that they're three separate beings.

Puppies are cute,

but they don't make great DJs.

With the comma,

you may think

Bob is the DJ,

and all you need is him and the puppy.

The argument over the Oxford comma

has raised such strong passions over the years

that a sort of truce has been reached.

The common wisdom is that

its use is optional,

and depends on whether it will help

to avoid confusion.

For one thing,

you're supposed to keep your use or avoidance

of the Oxford comma

consistent throughout a whole piece of writing.

So, using it only where necessary

is not an option.

And the very idea

of a grammatical rule being optional

is a bit odd.

Imagine that you hadn't messed up the party planning,

and read the next day that "everyone had a great time -

ninjas, pirates, vikings, old and young."

If the Oxford comma were standard,

you would notice it missing

and conclude that old and young

must describe the awesome guests already listed.

But as things stand,

you will always wonder

whether it means

that a bunch of regular, boring kids and old people

showed up as well.

Ultimately, the serial comma may be useful or annoying,

but your opinion on it,

as for many optional things,

probably has something to do

with whichever style you were raised on.

Your high school teachers favored it?

It's likely you're still using it.

Your first editor hated it?

You probably do, too.

And maybe so much hairsplitting

over a tiny squiggle on a page

is a bit silly.

After all,

there are so many bigger problems

to worry about.

But sometimes, little things can make a big difference.