Last week, my friend Matt Mays alerted me to a Farhad Manjoo piece at Slate.com about whether it was appropriate to put one space or two after a period at the end of a sentence. Farhad was correct: one space is appropriate. So why do lots of people still make two spaces?

Two spaces is a vestige of the typewriter era. As Manjoo pointed out, in traditional typesetting, the characters are proportionally spaced: skinnier letters take up less space than fat ones. But typewriter type is all monospaced; that is, each letter occupies the same amount of space on the page. People who learned to type on typewriters were taught they needed two spaces after a period for easier readability.

“Monospaced fonts went out in the 1970s. First electric typewriters and then computers began to offer people ways to create text using proportional fonts. Today nearly every font on your PC is proportional (Courier is the one major exception.),” according to Manjoo. I believe my partner Scott Woolgar had the last word on this one when he noted that, if you put two spaces in a row when you’re typing on your iPhone, it automatically adds a period. ’nuff said.

Lots of conventions in written language are artifacts of another era. I suspect another prominent one is the admonition to avoid the serial comma–sometimes known as the Oxford comma or the Harvard comma. It’s the comma that comes before “and” in a series. Like this:

  • With serial comma: The woods are lovely, dark, and deep.
  • Without serial comma: The woods are lovely, dark and deep.

You may believe there’s no difference between those two sentences, but I disagree (and I think Robert Frost would, too.) The first sentence describes three things about the woods: they are lovely, they are dark, and they are deep. The second describes the woods as “lovely”; “dark” and “deep” are modifiers of “lovely.” In other words, the woods are lovely in that they are dark and deep. “Dark and deep” describe the loveliness of the woods, not the woods themselves.

In the above examples, the presence or absence of that one little squiggle changes the meaning of the sentence. (Frost probably knew what he was doing when he left out the comma; an editor later included it and, to my ear, fracked up the line.) But I also think you need the serial comma for clarity. Consider:

  • This weekend, I saw my sisters, Arthur and Paul.
  • This weekend, I saw my sisters, Arthur, and Paul.

Again, the difference is just one little comma. But the first sentence could be construed to mean that my sisters are named Arthur and Paul. There’s no such confusion if you add the serial comma.

So why all the hate for the serial comma? Why did we ever stop using it? I believe it was primarily a newspaper convention. Newspapers used to be set in lead type, and lead cost money. Fewer commas meant less cost.

Fewer commas also took up less space in the newspaper. It seems trivial. But if you gather up all those Oxford commas and put them back into the copy, they add a lot of characters to a lot of lines.

Anti-serial comma advocates (or “heathens”) say the serial comma is usually unnecessary, and can actually create ambiguity. They’re right. Consider:

  • This weekend, I saw my sister, Grace, and Paul.

In this sentence, “Grace” could be my sister’s name, or it could be someone else.

But the careful writer would never settle for a sentence so ambiguous. There are twenty ways to write around the problem. You might also say there are twenty ways to write around any confusion created by leaving out the serial comma–and you’d be right there, too.

For me, the Frost example is convincing.¬†I think the serial comma helps make your writing clearer. Forces on my side include Strunk and White’s The Elements of Style and The Chicago Manual of Style–not to mention the United States Government Printing Office’s Style Manual and the American Medical Association Manual of Style. Forces aligned against include the dreaded AP Stylebook. Note that this stylebook was created for newspaper copy–and not for advertisements, books, poems, brochures, or the web.

So pull yourself out of the newspaper age. Embrace the serial comma. Also, embrace “Oxford Comma”: a catchy little song by Vampire Weekend. (Thanks to Hugh Vandivier for the reminder.)

And, yes: I’ve been watching Battlestar Galactica.