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Two Spaces After a Period Isn't Dead Yet

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Adrian Roselli

Member info | Full bio

User since: December 13, 1998

Last login: January 03, 2012

Articles written: 85

...At least not in my world.

After years of doing it correctly, I have gone and purposely done it wrong over and over again.  I know what is considered right (no double space) and what is considered wrong (double space), but after years of doing graphic design, I no longer follow that rule so closely.  I have two exceptions I personally follow, and nobody has ever noticed until I point it out to them (and then they chastise me for not knowing the 'correct way').   I know that professional typesetters use 1 space, and I know that typing teachers taught 2 spaces, and I know why.  In professional printing, you have what are generally well-designed typefaces with professionally tweaked kerning that shouldn't need the extra space.  For the old-fashioned typewriter, however, the text was in a fixed-width typeface (kinda like Courier) that did not aid the user in his or her reading of the text.  This drove the need to insert that extra space as a clue that the end of a sentence was coming (since people often see ahead of where they are reading, such cues are important).

For instance, in multimedia (which includes web design), your screen fonts are often not well represented in pixels and many characters butt up against one another while others space out further.  Kerning just doesn't seem to take care of that very well, as you can see in Word documents (or the occasional web site) that have been justified.  Since here we tend to lose the advantages afforded good typefaces in print, namely proper kerning and clean representation of the fonts within the small amount of pixels allowed, we lose our reasons for abandoning the double space.  In these cases, I add an extra space after a period to improve readability.

When using free fonts (from great sites like Chank), often the characters aren't properly spaced, and they need some help from the designer.  Again, sometimes you don't want to kern the entire document; you just want more space because the font designer made his period have no space on the right.  In this case, I will use a double space.  I have found that in print, most designers tend to not notice this until I point it out.

I used to follow the rule precisely, but after years of looking at my stuff and being disappointed at legibility, I made the conscious decision to abandon or modify that rule in certain cases.  Rules are made to be broken, aren't they?

I was reading an article from Scientific American while riding on the tube the other day, and I ran across the following block of text:

"...to determine whether they were commercially viable in the U.S. Ware and his colleagues concluded that the green and the brown cotton yielded too little..."

When I first read it, it took me a few times of re-reading to recognize that Ware is a person's name (as explained earlier in the article, I just forgot since I am bad with names), and not some government agency (US Ware?).  The single space in this case, coupled with the justification of the article (removing the consistency of spaces between words from line to line) confused the heck out of me.

I found myself wishing they had an intern who incorrectly added another space after years of being traumatized by an unruly typing teacher in high school, because then I wouldn't have been so confused.

A founder of evolt.org, Adrian Roselli (aardvark) is the Senior Usability Engineer at Algonquin Studios, located in Buffalo, New York.

Adrian has years of experience in graphic design, web design and multimedia design, as well as extensive experience in internet commerce and interface design and usability. He has been developing for the World Wide Web since its inception, and working the design field since 1993. Adrian is a founding member, board member, and writer to evolt.org. In addition, Adrian sits on the Digital Media Advisory Committee for a local SUNY college and a local private college, as well as the board for a local charter school.

You can see his brand-spanking-new blog at http://blog.adrianroselli.com/ as well as his new web site to promote his writing and speaking at AdrianRoselli.com

Adrian authored the usability case study for evolt.org in Usability: The Site Speaks for Itself, published by glasshaus. He has written three chapters for the book Professional Web Graphics for Non Designers, also published by glasshaus. Adrian also managed to get a couple chapters written (and published) for The Web Professional's Handbook before glasshaus went under. They were really quite good. You should have bought more of the books.

Did anybody ever read this?

Submitted by aardvark on March 2, 2001 - 00:30.

I feel bad seeing an article with no comments, whether or not it deserved any. So, I might as well add one, and a useful one at that. Another decent article on the spacing issue, written around the same time as this one, is One Versus Two Spaces After a Period, over at webword.com. Clearly they didn't this article good enough to link, but I didn't even see theirs until a while ago, and it's taken me forever to post it. So, how often do you carry on conversations with yourself?

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Nice post

Submitted by biz on May 17, 2001 - 15:48.

I found your article while searching for evidence that two spaces after a period are wrong so I could tell my friends to stop doing it. You make some good points though. I see how in some cases two spaces might help. But overall, two spaces bug me.

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Old-fashioned

Submitted by monelle on July 20, 2001 - 20:24.

I was asked as a mother-in-law (ugh) to settle the argument: 1 or 2 spaces. I'm 54 years old and learned 2 in Typing class in high school. I've always been interested in language, printing and aesthetics, and I definitely prefer 2 spaces. However, it must just be an old habit, because I just picked up a book and saw to my amazement that the spaces are the same after commas and periods! How can it be, I ask myself, that I never noticed this before, even though I conscientiously add another space after every period in the e-mails I forward? Reading your article seems to indicate that the answer is "kerning," whatever that is (I just looked it up at http://www.meriam-webster.com/cgi-bin/dictionary and it's not there). Anyway, thanks much for your very thoughtful article.

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Kerning links

Submitted by aardvark on July 22, 2001 - 10:45.

Here are some links on kerning:

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Finally, someone agrees with me.

Submitted by DanTimis on May 26, 2002 - 01:30.

I found this article while searching for arguments for using two spaces after a period at the end of a sentence in email messages.&nbsp&nbsp I got into an argument about this issue on a mailing list.

I use one space with a word processor where I have control over the font in use.&nbsp&nbsp With email, or with postings like this one, you never know what font will be used, so I prefer to err on the side of caution and use two periods.

Thank you.

Dan

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Damn the developers!

Submitted by lizard on January 7, 2003 - 10:07.

At last, a Web professional willing to concede that the extra nbsp is worth the effort.  Reading online is hard enough without endings that are difficult to observe.  Many Web styles were initially codified by a select few who wrote enormously popular books on Web development, but that does not mean what they deemed appropriate is best.

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double spaces between sentences

Submitted by EugeneRWalker on March 10, 2003 - 19:26.

I have tracked the debate over one versus two spaces between sentences, but the decisive issues have not been raised until now. Web developers and office correspondents root for one space; "diehard" typing teachers, say, still insist on two. This depends on just what one is doing. For manuscript submission, the correct answer is still TWO--period, double space. In finished productions (business letters, Web pages, magazine articles, books) the double space does indeed go away, BUT ONLY WHEN THE TYPESETTER OR FINAL EDITOR KILLS IT. This criterion is grounded in history, which has not been mentioned adequately in the online debate. The double line-spacing in manuscripts allows the editor(s) to add marks and notes. The double letter-spacing between sentences helps the typesetter's eyes to look from the manuscript to the typset work, then find the place again in the manuscript. The typesetter, however, never carries the double space over to the finished product. If you, as an author, would like the typesetter to dribble a few of your sentences onto the floor--or duplicate them, making you look like an idiot--by all means feel free to ignore this fact. The editor who accepts or favors single spaces can do just like the typesetter--mentally omit the second space from paper copy, or with a few keystrokes turn all the doubles into singles in electronic copy. BUT YOU CAN'T GO THE OTHER WAY. If the writer or an earlier-than-final editor deletes the second spaces, and then a later editor or typesetter wants the double spaces, somebody has to go through the whole piece sentence by sentence to fix it. This is the perfect fate for the nitwit who doesn't know what the rule is, let alone why.

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I'm for using two spaces

Submitted by jleblanc on March 11, 2005 - 13:13.

Adding two spaces after a sentence is just as important as determining how paragraphs are separated.  Just imagine if we didn't do hard breaks or add spacing between two paragraphs:

Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  
Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine.  Just imagine. Just imagine. Just imagine.  

It looks jumbled and sloppy and reading an entire page like that would really annoy me!  At face value, the kerning explanation may seem a valid reason for the extinction of two spaces, but it is a moot point.  If you apply Human Factors principles (which are way more important than kerning) then two spaces is still very necessary.  The reason I state this is because, if you are a writer by trade, your first responsibility is to keep your audience in mind.  Over the last fifteen years, my audience has always comprised of engineers and/or executives that read hundreds of pages every week.  If they have to think about whether or not it is U.S. Ware or U.S. then Ware, they are going to get frustrated and I will eventually lose my job.  To me, it is not a burden to type two spaces after each sentence, it is a requirement.

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Well, all they actually need

Submitted by GabiO on June 28, 2006 - 19:27.

Well, all they actually need is a good editor. All style manuals I can think of recommend that U.S. be spelled out (United States) when used as a noun. The abbreviated version (U.S.) is used only as an adjective (the U.S. economy). Don't you think that people should learn to write and edit better rather than rely on mechanical means such as double space to convey their thoughts clearly?

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Your comparison of the

Submitted by GabiO on June 28, 2006 - 19:46.

Your comparison of the double space with the paragraph space isn't quite right. The paragraph space is necessary only if you do not indent the first paragraph line. So the graphic example you provide actually corresponds to no space between sentences. The equivalent of the double space would be a paragraph space *plus* indentation of the first line, and that's clearly unacceptable. If you are a writer by trade you should easily be able to avoid no brainers such as U.S. Wane. I also believe that plain and proper English helps our audience better than double spacing.

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adding two spaces in HTML

Submitted by Biddy on November 4, 2007 - 16:22.

I notice that you're adding two nbsp characters after each period to get a double space since HTML ignores more than one space character. In HTML it makes more sense to use nbsp followed by a regular space. That way the source code can break after a period, instead of forcing the last word of the sentence down to the next line with the first word of the next sentence. Unfortunately, programs like OpenOffice swap the order and stick the nbsp to the front of the next sentence, rather than to the preceding period which caused the need for spaces in the first place. Oh, and it seems to me that whether to put one or two spaces should include this information: Is the text justified or left-aligned? It matters more which you choose when the text is justified. Does the author prefer the added space for an extra visual clue? This matters, too.

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3 spaces after a period should be dead

Submitted by Gary Lutchansky on January 24, 2008 - 22:14.

Thank you for this post. It's good to learn about other people's viewpoints. Back in the early years of computing, I switched from repeatedly batting the space key. It's easier to hit it only once. And it has become a standard.

Letting two spaces after the period die is the way to go. Why? Well, you have to fight to maintain it. It's not worth the effort. Further, two spaces has become nonstandard. Reading your well-written post bothers me slightly because of the "extra" spacing. It looks different than what I read EVERYWHERE else. The comment from Biddy noticed your insertion of 2 nbsp characters to get around the HMTL limitation where extra spaces are ignored. Too much work! Plus, in the effort to maintain 2 spaces yet another space gets added. For example, consider the first real paragraph of this article before "I know that professional typesetters..." Three spaces is too much!

The "...U.S. Ware..." example that removes the start of one sentence and the end of another to highlight the confusion of single spaces after a period doesn't move me. Those who view this example positively--including you--don't show us how it should look with the two-spaces approach. Fact is, it doesn't look much different; there is a chance for confusion either way. Readers can be forgiving when confusion doesn't strike at every period. Or, as other comments suggest, the sentences could be changed.

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Can't agree

Submitted by jopejope on February 25, 2008 - 03:32.

You make a few interesting points, but I don't think that extra little sliver of space is needed, even in a few of the situations you specify. People's eyes (brains) adjust. Just let go, I say. We can all spot the end of a sentence just fine without a massive chasm of blank to telegraph it.

Also, I can't bring myself to agree with you on the Scientific American example. It just sounds like you're desperately trying to defend an outdated practice that you feel some familiarity with. It is perfectly clear from the context and wording that the sentence does not end there. Also, since the phrase up to "in the U.S." is introductory, a comma is warranted after it. This would make things much clearer. You could find phrases like "the U.S. Treaty on . . . " But even that's clear from the wording.

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Context

Submitted by nthn200 on November 26, 2008 - 04:14.

The fact of the matter is that type never used two spaces between sentences until the invention of typewriters due to the fact that the machine had one setting for inserting width. The kerning was uniform (fixed width), which necessitated the distinction of two spaces after periods. It may be more convenient for people reading a document to have this extra separation for the readability of very large documents, but when making design decisions with quality typeface, for quality pieces, it is not only a space-saver, but lets the typeface perform its engineered utility, creating the aesthetically appropriate amount of space between sentences.

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It's a Style Thing

Submitted by seiun on May 2, 2009 - 11:43.

Typography is all about clarity and readability. In my opinion, it's a style thing. If you believe that two spaces after a period make your copy more readable (as I do), then by all means, use two spaces. The problem, of course, is that you'll be fighting with html rules. But if you're a word geek, it's a mistake to allow the code geeks to ruin your plans. So I say drop in those non-breaking spaces wherever you feel they're needed.

By the way, your Scientific American example needed a comma for clarity--not another space. Like this:

"...to determine whether they were commercially viable in the U.S., Ware and his colleagues concluded that the green and the brown cotton yielded too little..."

Double spaces after periods are not outdated, as some have stated. Not any more than paragraph breaks and italics and bold fonts. It's all about clarity and getting your point across.

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One space after all punctuation...

Submitted by adora on May 28, 2009 - 14:20.

Your example is irrelevant. As mentioned previously, U.S. should have been spelled out. Furthermore, there should be a comma after U.S. (or United States). That would take care of any misunderstanding. It's not an extra space's job to do that...

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Typesetting

Submitted by TechieMcD on August 12, 2009 - 12:00.

Back in the day my middle school ran the "prep" kids through typing and printing classes. This was OK, but metal shop would have been more fun than typing. So, what did I learn? Using two spaces after a sentence on a monospace typewriter is consistent with typesetting, where an em space is used between sentences and for indents. In a proportional font, the em space is about the size of an M, so it makes a fairly wide gap when compared with word spacing. Extra space between sentences enhances readability in most cases, which is what art of font design and typesetting is all about. Look at your books and you'll see that many of them have wider gaps between sentences than between words. It may seem odd to someone who has grown accustomed to narrow gaps in word-processing text, but consider that typesetters perfected their art over centuries, not decades. P.S. Be glad you don’t have to justify your text using individual thin spacers from a job case (yes, there are upper and lower cases). Some modern conveniences are useful. So are em spaces after sentences.

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One space or two ...

Submitted by Rex1029 on August 29, 2009 - 22:38.

Good article and numerous good comments. Consider the space and multiple spaces as punctuation. Use them appropriately and sparingly. In writing material to be printed an extra space may force a new page which may increase cost which may increase price which may decrease sales which may decrease profits. Also, more than zero Web browsers replace sequential multiple spaces with a single space. This may change the presentation into something undesirable. Especially for those who use spaces for aligning numerals and text in columns and other such tasks. Those using Associated Press, MLA, APA, or subject matter specific style guides are out in the lead. A GOOD dictionary usually has formatting and style information in it. The goal is at least two-fold – readability and consistency. Thanks, Rex

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One space - Kern, Kern, KERN!

Submitted by yuppett on November 6, 2009 - 03:22.

One space after puncutation is the right answer. Any professional typesetter, editor or graphic designer should know this. There is never a reason to use more than one of anything if you know what you are doing. You should never hit enter, tab or add a space more than once. That is why things like kerning, leading, tracking and space before and after paragraphs were invented. If all these tools are used properly then readability will NEVER be an issue.

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A few things...

Submitted by Blain20 on January 25, 2010 - 08:17.

The only thing I disagree with you on is that the 2-space rule is not the rule! My teacher said to do it, so I'm doin' it!

I program for a MUD (multi-user dungeon/dimension) which is a text-based online RPG. MUDs use fixed width fonts, but for some reason, most MUDs use 1 space after a period. Luckily, the MUD I work for will allow a contributer to use 2 spaces so long as they are consistent throughout the particular project. We do, however, get into it a lot over the subject. I'm one of the very few that does use 2 spaces. And I use 2 spaces always, everywhere. I use the period-nbsp-space rule for HTML, even. I can understand using the 1-space rule in a variable-width font situation, but I never resort to it myself. I've never written a Word document and thought it was ugly for being 2-spaced.

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Too many "authorities"

Submitted by Certo on May 27, 2010 - 03:46.

I guess I am not as smart as some folk such as yuppett (two posts above). How he/she can "Kern, Kern, KERN!" everytime he/she types is way beyond me. On looking at yuppett's post, the Y and the T almost overhang the preceding periods. Kern baby, kern! I don't mean to pick on yuppett. He/She just happens to be viewable on the screen. I agree with Adrian Roselli. Not only do I write a great deal, I am a musician. Adrian noted how readers see ahead as they go. So do musicians. There is something to be said for ease of reading comprehension when sentences are sufficiently segregated. Far too many internet sites have guestbooks and other entry forms that kick out double spaces, paragraph breaks, etc. At least there's no debate over indenting the first line of paragraphs. I am double spacing this post. We'll see how the software displays it. I asked a friend who is grammatically crisp about this. While it's not grammar, per se, I figured she'd at least have a clue. Too be sure, she scoured the internet and found this thread. Anyway, the only time I don't double space between sentences is in a post that allows only so many characters and I need about 4 of my extra spaces back. Some of the web design gurus, techno genius types, create some pretty elaborate applications. But that doesn't mean they made anything more than a D minus in English, took any hints from a writer or so much as wrote 20 sentences outside of millions of lines of code. That's my two cent's worth and two spaces per sentence. -- Aaak! Preview shows another web design genius more concerned with server space than what some "authorities" say isn't right. May you all be blessed with double spaces.

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well now i'm confused

Submitted by sakoide on June 4, 2010 - 16:32.

I just like two spaces. I know why it's not important anymore and why typesetters and designers prefer one, that makes sense. I hate rivers of whitespace, too. But I do just *like* two spaces more, probably from learning it for typing class. I am considering getting a small run of t-shirts made that say "two-spacer", though.

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Spaces between sentences

Submitted by TonyM on August 31, 2010 - 09:51.

I write persuasive letters, e-mails and reports for a living (well part of it, anyway). I always refer to my work as an ‘art’, because I paint pictures with words. I want the reader to see the same view as my own. Note that this is not a view in the sense of an image – it is ‘view’ as in ‘opinion’ – I want the reader to see and adopt my point of view.

After 30 years of typing two spaces, I only became aware of this debate when my son, who works for a web design company, mentioned that he had been told to change from the two spaces that he had been taught at school.

Lets look at the arguments.

The most common argument found on the internet is that ‘monospace’ (or non-proportional) fonts used on typewriters required the extra space to ensure a clear break between sentences. In my view this is nonsense – you actually get more space between sentences with monospace than with proportional fonts, because the spaces are the same width as the letters. Indeed, with monospace you also get a full letter width for the full stop, so the actual white space is huge – with two spaces after the full stop you get the width of three spaces between the edge of the last letter in one sentence and the first in the next. It seems to me that the monospace explanation has been ‘retrofitted’ to the argument.

Perhaps the other side of same argument is that the design of modern proportional fonts makes sufficient allowance for the extra spacing, making it unnecessary to double this up by adding a further space. I think this is a “King’s new clothing” argument – “surely you must be able to see it..?!” The answer is “No!” I haven’t applied a micrometer to the task (and shouldn’t need to..), but the space looks the same as any other – no larger for following a full stop.

Then there is the argument that typesetters have always used one space, so it must be right. But maybe this is the key to understanding the issue – if you have to set a book with say, 60,000 words and an average of say, 12 words per sentence, then this amounts to 5,000 sentences – or 5,000 extra spaces – a lot of ‘unnecessary’ work, if you are a typesetter…

And the typesetter’s employer, the publisher, is not going complain at his laziness – not only does it save him labour costs, if we assume an average of 5 characters per word, then the additional 5,000 spaces could add half a dozen extra pages to a good book – more paper, more printing time, more transport costs etc.

Then there are those people who, long ago now, set the ‘standards’ for electronic recording of the written word and decided on one space only. If, like me, you remember when the value of every last character had to be measured against the memory it used up, you will not be surprised that the techies regarded the extra space as an unnecessary waste of space.

Finally, we have the supposed ‘rivers of white space’ produced by the occasional alignment of the double spaces within a block of text. In the early days of word processing, the facility to align the text both left and right was a sign of technological advancement – a sign that your organisation had arrived in the technological age. Unfortunately, the alignment was achieved by stretching each character and, particularly with early monospace fonts, this produced excessive spacing when two spaces were typed after the full stop. So the simple answer was to type just one space. Of course, these days, left and right alignment are considered rather ‘passé’, with the result that the extra spaces no longer produce rivers of white space.

The simple fact is that the decision to use one space rather than two has nothing to do with what looks best to the reader, but what suits the producer of the written word.

So what about the arguments in favour of the double space? The extra space, as most would concede, along with the full stop and capital letter to start the new sentence, provides a valuable visual signal to the reader. It’s as simple as that. And ironically, on this basis, proportional fonts which (for the reasons outlined above), result in less white space between sentences than monospace fonts, actually increase the need for the extra space to be inserted.

Of course, readers of pulp fiction don’t care too much about punctuation – they don’t absorb the text in sentences, but just pick up the gist of the story by scanning it. They certainly don’t write to the publishers to complain. And, no doubt, people who have been ‘brought up’ on a single space may actually find the extra space slightly odd.

But when it comes to persuasive writing, you want to control the pace of your reader’s thoughts. The use of sentences and paragraphs becomes crucial. The last thing you want is for the reader to merely scan your work – you want them to take it in bite-size chunks.

So if you write books, then stick to one space, because the publisher will probably delete the spare spaces and subsequent use of the ‘track changes’ facility in Word will drive you up the wall with the 5,000 or so changes that they’ve made …

And if you write web-sites, then carry on, because even though computer memory is no longer an issue, you probably don’t want your text to take any more space that it has to. And few people read the entire content of a web-page anyway…

But if you want to speak to your reader as an attorney would address a jury, or as a president might address the nation – bite sized pieces of information – then use enough space to make each sentence count.

(Having previewed my comment, I see that what people say about forums automatically deleting the extra space is right – unfortunately the techies still rule… Come on guys – the cost of computer memory fell years ago – catch up, wont you…!? How can I write a persuasive comment if you refuse me the tools needed to do so…?)

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Rules may not be applicable to every discipline

Submitted by Paul5388 on January 15, 2011 - 02:57.

I thought I remembered a book that would address this issue that should have been on my bookshelves. True to form, it was right there, a copy of “Writing, A College Handbook” from a course at Stephen F. Austin University. On page 439, I find these words, “When typing, skip two spaces after the period before beginning the next sentence.”

Now, it must be realized that I am typing to write this post and I'm using two spaces after sentences, regardless of what the software does.

The acceptance of certain styles really doesn't have much bearing on what's proper, as evidenced by many of the “shorthand”, or “texting” formats being accepted as normal.

There was a time when paragraphs (semi-block) were separated by two lines and in addition, the first line was indented. There are also two other paragraph formats, so writing isn't to be confused with other pursuits and it does have rules that may be at odds with other communication forms.

I also remember back in the fourth grade (1954) I used a spelling I found in a book on a spelling test. The teacher wasn't impressed with "harbour".

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I have always been sure that

Submitted by JackieKyle on September 25, 2011 - 17:10.

I have always been sure that it's a mistake to put two spaces after a period. Surprising...

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Great posting

Submitted by David Wallace on September 30, 2011 - 10:10.

Congratulations on an intelligent and well thought out posting. I've never understood the recent trend towards single sentence spacing, nor the vehemence of those authors who insist that "double sentence spacing is always wrong". The comment by TonyM from 31/8/2010 (no, I'm not American) was fabulously insightful too.

I wonder whether jopejope (25/2/2008) and seiun (2/5/2009) actually realise that their comments SUPPORTED your point of view, by demonstrating that they had not realised that "U.S." in your example was the end of a sentence, rather than the end of an introductory phrase.

I have always used two spaces after sentences, and always will do. It obviously makes text more readable; which at the end of the day is all that really matters. If that puts me in a minority, then I feel sorry for the majority.

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