Back in high school, I was taught that when typing, one put two spaces after a period. This has always served me well and in fact, it irritates me somewhat that forums such as this automatically reduces the two spaces to a single space when the message is posted. Recently though, I was reading an article in a computer magazine and it mentioned in passing people who “still incorrectly put two spaces after a period.” Has this changed? When? Why? And why wasn’t I informed?
I had this argument at work with my boss and ex-girlfriend. They both insisted that you double space after a period. I insisted they were wrong. That evening I took a trip to the bookstore to prove my point.
The APA Publication Manual, among others, stipulates that there should only be one space after periods. Word processors and programs can get screwed up with double spacing if you’re trying to change formats. Like copying WordPerfect to Microsoft Word…although I doubt it would happen with these two.
Yep, it’s only one space now.
People used to have to type two spaces after a period because typewriters almost always use monospace characters, where an ‘m’ is exactly the same width as an ‘i’. If you only use one space with this kind of font, it doesn’t look as good and may be harder to read.
But now that we have computers, the fonts are designed to look good with only one space.
The true test: pick up any book. They only ever use one space, never two.
I might also add that on typewriters, you had to underline because typewriters can’t do italic letters. But since your computer can, please do. Stylistically, it’s the same.
And why weren’t you informed? Oh, believe me, there’s a LOT they aren’t telling you.
I’ve always put one space after a period, comma, etc. Some people put one space before and after the period. Those people are strange and should seek help. 
The comments about monospace typefaces (Times New Roman is a typeface. Times New Roman 12 point is a font. Times New Roman 13 point is a different font.) sound accurate. It can surprise some people how much we derive our standards from the obsolete limitations of typewriters.
Personally, I prefer the single space after format. It is the standard in nearly everything I’ve read, so text in a different format looks odd and is distracting.
I think I’ve answered this question before…
The reason for the extra space after the period is two-fold: readability for editors, and practicality for typesetters.
As a wanna-be writer, I type everything in Courier New 12 pt. This is a non-proportional font, with every letter taking up the same amount of space, and is pretty much the standard for editors–they’re accustomed to reading it. It’s easier to read if there are two spaces after every period.
It’s even more important for typesetters, though, putting your book into print. These guys work rather quickly, and so they don’t want to miss something. Thus, after semicolons and commas, you place one space; after colons and periods, you place two spaces. The two spaces is a quick “signal” to the typesetter’s brain to make sure he’s put in a period rather than a comma.
For me, the extra space after periods and commas in completely ingrained. <shrug>
LL
My friend and co-writer, an editor, brainwashed me into using only one space after a period. We had an argument about it that lasted about five seconds and ended with him saying “pick up any magazine.”
Wow, another thing I didn’t know. I still put two spaces after a period, and I don’t know if I would be able to stop, it’s such a strong habit. I think it reads much better that way, easier to tell when one sentence ends and another begins.
Another punctuation thing I do which I thought was correct but seems to be changing was use of commas in a list. I will type “I invited John, Peter, Sally, and Jim” instead of “I invited John, Peter, Sally and Jim”. To me not putting that last comma in there seems to somehow connect the last two parts of the list, in the above example it looks like to me I am implying Sally and Jim are a couple.
I agree with Badtz Maru on the 2-spaces-after-periods thing. It’s so automatic for me that I’d have a hell of a time breaking the habit.
I seem to recall reading somewhere that a comma after the last item in a list is considered optional now. I’m a strong proponent of using parentheses and brackets to show groupings in complicated sentences, kind of like the way they’re used in math. Nobody who reads my writing seems to agree, though, so I’m left to rail against the needless ambiguity of English grammar. 
So then, supposing I want to believe the fascist, paramilitary APA and only use a single space, when did they decide this? After decades of using double spaces (centuries? I don’t know if they cared about this stuff when Guttenburg got started), one day someone from the APA was using his copy of Bank Street Writer and said “Hey! We can get by with only a single space if we stop using monospaced fonts!”? Do they vote on this sort of thing? Or was it just that after watching magazine editors screw with their rules, the APA said “the hell with it” and changed the standards?
I always put two spaces after each period and I have never had any problems with it on any word processor. The programs may parse the extra space out, but that’s no skin off my nose. Sure, I read magazines and other professionally-published stuff all the time, which might be only spaced once after the period, but they never look noticeably different from anything I write. The only thing I can’t stand is when people don’t put any space at all after the period. Failing to do so causes weird justification problems.
thought this was a “female astronaut” thread. Guess not.
I still double-space after periods, being taught how to type in the typewriter age. But as a computer programmer, I know that whitespace in HTML documents is trimmed down to one space’s worth when rendered using a browser. But I think word processors still make single and double spaces look different.
As the owl said, “Let’s find out”:
This is a sentence. This one has two spaces before ‘this’.
This is a sentence. This one has one space before ‘this’.
This sentence is triple spaced between words.
This sentence is double spaced between words.
This sentence is single spaced between words.
Thissentencehasnospacingbetweenwords.
You have to differentiate between typing and typesetting.
Typing always mandated two spaces after a period. Typesetting used one. Standard manuscript format nowadays still requires two spaces, since it should be done in a monospaced font (this is essential if the editor wants to get an accurate estimate of the length of the piece).
When you’re using a word processor, you are combining both typing and typesetting. Best rule of thumb: if you’re typing a manuscript for professional submission, then use a monospaced font (usually Courier), double space, two spaces after the period, underline instead of italics, no “smart quotes,” etc.
If you’re typing for your own use, or for a business, you can use whatever system you want, provided you are consistent.
The way it was explained to me was that newspapers use only one space after the period to save space. When I was in school, the teachers always insisted on two spaces after the period - because there are no space restrictions in school papers and because the teachers want to be able to read the paper more easily (especially considering some teachers had scores of papers to grade).
It really does come down to typesetting - I think that the more space-restrictive the medium is, the more likely it will have only one space after the period. Online literature should, by that logic, have two spaces following the period. (I was also told that books were always different from newspapers, as they had two spaces.)
Badtz Maru, I feel your pain about the comma, known in editorial circles as the serial comma (sounds kinda creepy, doesn’t it?). AFAIK the common practice nowadays is to include that final comma, but I also believe it’s a style issue. If the publication in question chooses to follow, say, Chicago or AP or if it wishes to form its own style on the issue, no one’s gonna tell them they’re wrong. It’s NOT wrong to not put that final comma, but you really, really, really need to be consistent with it within your publication. (Personally, I put it in.)
I, too, show my age in that I learned to type on a typewriter and the double space long ago became second nature. I still do it when I type here even though I know the extra keystroke is wasted.
There is only one thing I hate about the single space after a period: What about when the sentence ends with an abbreviation? The period at the end of the abbreviation also functions as the period at the end of the sentence. If it’s followed by a single space and a capitalized proper noun, the sentence boundary becomes invisible! Example:
“The situation depends on the response from the U.S. Navy SEALs are on the way…”
See? It was supposed to read:
“The situation depends on the response from the U.S. [sentence boundary] Navy SEALs are on the way…”
That can be really confusing for the reader! If you were reading out loud, you would be certain to run over into the next sentence without pausing, only to experience a sense of doubt, then have to backtrack and try to puzzle out the sentence structure. Embarrassing.
The spacing issue was touched upon in this thread.
One of the main points from the early days of word processors is that if you double-space after a period, you can get a blank space at the beginning of a line.
Here’s a tidbit I learned in English Lit:
In the Robert Frost poem, Stopping by woods on a snowy evening, the line goes:
The woods are lovely, dark and deep.
At one point, it was published in a collection, and someone mistakenly inserted a comma:
The woods are lovely, dark, and deep.
This changes the whole meaning of the line. The former, as written by Frost, says “the woods are lovely because they are dark and deep.” The latter, the mistake, says “The woods are lovely and they are dark and they are deep.” The mistake was fixed in the next edition.
This to me illustrates why the serial comma should not be optional. If the items are a list, it should be included. If it is absent, that indicates that the last two items are not separate items on the list, but somehow realted to one another.
(For the record, I always put in 2 spaces after the period. My ma taught me that. I should ask her if she still does it.)
That Frost example is very good! I’ve never seen it before or heard of it. But I think I would have interpreted the original (as I have in the past) to simply mean that the woods were lovely, dark, AND deep (all three). I haven’t researched this, but there must be research of some sort (maybe even from Frost) that indicates his intention? (Not saying you’re wrong, and it’s been a while since I studied him, if ever!)
And not to knock a great poet, but if he meant the woods were lovely because they were dark and deep, then the wording’s at least a little vague I think if I had been his editor I would have stupidly told him to redo it…
Oh, back to the two-spaces thing (the OP, right?)… When I’m typing on the ol’ keyboard, I use one space, 'cause I’m lazy. 
Dantheman is correct – single-spacing after a period is a journalistic exercise. Prose style is two spaces after a period. Newspapers began single-spacing their periods to conserve space – or, more accurately, to create more advertising space in the same number of pages.