Should you feel the need, today (September 24) is the perfect day to get out there and correct all of those silly grammatical errors you see everywhere you go. There’s the grocer that puts an apostrophe in with his potatoes, the Facebook snark who uses speech-marks for emphasis so it looks like they’re unsure about everything they say, and worst of all, the grammar pedant who makes simple grammatical errors while correcting someone else’s simple grammatical errors. Under normal circumstances the best advice with any of these crimes against language is to leave well alone, but hey, it’s Punctuation Day. If you can’t tear someone a new colon today (or semicolon, if you’re feeling merciful), when can you?

And while we’re looking at the dots and squiggles that pepper our sentences like snow on a winter windowsill, let’s answer a question about what we should all really be calling the mark that calls time on all of our sentences; the handbrake to a thought; the end of the line for words in a queue; the crash barrier to all discourse—the period.

Or, as the Brits insist on calling it (with a fairly typical bleak outlook) the full stop.

We should all pause a moment and thank Aristophanes of Byzantium for inventing this handy signal, without which all of our sentences would run on and on and on and even though we would be reading them and breathing at the same time somehow the mind would start to fog over as if suffering from an overwhelming lack of oxygen similar to that which would occur if one was to just talk and talk and talk and talk without pausing to take a breath or allow anyone else to interrupt or take a drink until everything went black and the floor came up and walloped us in the face. The period is a literary life-saver.

Aristophanes’ original plan was that there should be a high dot (˙) for the end of a sentence, a middle dot for a completed section of a larger thought (·), and a low dot which broke ideas up still further. His high dotted, completed sentence was called periodos, and it refers to an entire entity, a nugget of thought or time or experience with a start and a finish.

From this came the idea of the final flourish, the mark that provides a boundary between one idea and the next. So in a sense, at the end of a period lies a full stop, although no one ever says that. A distinction was made during the 18th and 19th centuries between the period—the dot itself, also used to end abbreviations and initials—and the full stop, which is only ever used to end sentences. British and American English were of one mind on this, even into the 20th century. And then, for reasons that are not entirely apparent, the generic term for that dot shifted within British English, and it became more commonly referred to as a full stop even when used for other purposes.

This then gave rise to an interesting cultural quirk that is more common in American English than British, the use of the word period at the end of an argument to indicate finality: “You stink because your whole family stinks. Period.”

I have to say that, despite this usage appearing in enough American English media for Brits to fully understand what is being said, it does prove a little distracting. By far the most common use of the p-word in British English, if used on its own like that, would be in reference to menstruation. They may know in their minds that the angry person on the screen has just concluded a rant (“PERIOD!”), but it won’t prevent a moment of mild confusion—not unlike that which would occur if someone had finished their professorial thesis with a one-word obscene signoff—like todger—which is the very opposite of the concluding effect that was intended. And it’s tempting to conjecture that it’s squeamishness about this double meaning that led British minds to settle on full stop (although there’s very little evidence to support that theory).

Oh, and here’s one last tip. If you’re American and used to putting a period after abbreviations such as Mr. and Dr., you may like to know the British don’t do that if the abbreviation contains the first and last letters of the abbreviated word. They’ll still put what they call a full stop at the end of Doc. or Prof. but the general trend is away from over-punctuating. Similarly it’s less common in British English to leave the periods in abbreviated names—like with JK Rowling or AA Milne—or acronyms such as USSR, US and UK. And if you put a quote at the end of a sentence, they like their full stops after the closing quotation marks, “Like this”.

Of course, ever since the advent of internet URLs, they’ve also been called dots, so who knows what will be sitting at the end of our sentences 100 years from now…

Not that, that’s an ellipsis.

See more:

5 Words Anglophiles Should Really Use More Often

Why Brits Spell Words Like ‘Realize’ With an ‘S’

10 British Words for Illness

Why Did America Drop The ‘U’ In British Spellings?