How to use full stops | A.k.a. periods or terminating punctuation
How to use a full stop, a.k.a. a period
You could be forgiven for thinking that one little dot has a single purpose but, depending on where you’re writing, there are a few more guidelines. In British English, typically, there is but one use. In American English there are a handful more. Both make use of the most commonly understood guideline:
Use a full stop (period) to end a sentence that isn’t a question or exclamation.
Simple. Anything else?
Using a period to indicate abbreviations
In American English, abbreviations traditionally require a period to indicate the missing letters. For this reason, it’s also typical to add a period after a person’s initials and for acronyms, since initials are a form of abbreviation.
E.g. Mr. Jones, A. A. Milne, and U.S.A.
The more common modern style is to drop the use in acronyms. Even the Chicago Manual of Style has depreciated them, although the Associated Press Stylebook generally hasn’t.
In British English the full stops are more commonly omitted, except in a handful of situations. Traditionally they were only required if the abbreviation did not comprise of the first and last letters of the word; vs wouldn’t need a full stop, for example, but prof. would. Nowadays, it’s common to forgo even that.
Full stops are still used in certain latin abbreviations, but not all of them. E.g. and et al. still require them, but it’s now more common to see am and pm without and in lowercase. All this from the version of English that prefers “logical” punctuation.
So why two names?
It’s generally agreed that both the words period and full stop came into use around the 16th century—full stop possibly being ever-so-slightly older. Period derives from the latin periodus meaning both “a complete sentence” and “recurring portion, cycle”. It’s presumed that full stop came about by contrast to lesser stops, such as commas. There is no right or wrong with either noun.
At this point, I should note we have Aristophanes of Byzantium to credit for developing a means to organising our thoughts at all. He first introduced a series of punctuation marks, including the full stop (a high dot), to help speakers/readers understand when to pause for breath. So we can also credit him for the concept of editing, really—otherwise we’d be stuck in a world of neverending, run-on sentences.
I see something contradictory and poetic about period: The end of a sentence should be definitive, a complete thought. Then again, our thoughts are never at a complete and finished stop, except when we ourselves come stop, macabre as that is. So, implying a cycle and a period of time before the next expression seems correct. Certainly more uplifting. All that being said, it does render the finality of expressions such as this a little impotent: “That’s the final word on the matter! Period.”
But, nevermind all that, right?
As much as it makes for fun pedantry, it’s good to remember that all these guidelines and rules and symbols came from a desire to express ourselves clearly. And what we stress, how we read, what we say—it’s all constantly evolving. Learning the rules is just a means to breaking them elegantly. Beyond anything else, if someone understands what you’re saying, surely that’s the only thing that matters.
