According to this Slate article “Space Invaders: Why you should never, ever use two spaces after a period“:
Typing two spaces after a period is totally, completely, utterly, and inarguably wrong.
More from the article:
Ilene Strizver, who runs a typographic consulting firm The Type Studio, once wrote. “When I see two spaces I shake my head and I go, Aye yay yay,” she told me. “I talk about ‘type crimes’ often, and in terms of what you can do wrong, this one deserves life imprisonment. It’s a pure sign of amateur typography.”
MP: I confess that: 1) I wasn’t even aware of this issue, and 2) I’m totally “old school” on this rule, probably because I learned how to type on a manual typewriter many years ago and was taught the “two space rule.”
Comments?
HT: Paul Sebastian




I’ve never, ever used two spaces after a period. In fact I didn’t even know there was some sort of rule about it until I read this today.
Back in the days of typewriter and fixed-width fonts (Courier on your dot-matrix) it was essential to have two spaces after a period otherwise it was difficult to tell when a sentence ended… Nowadays most fonts are proportional and the extra space in unnecessary.
–Ed
I read Jan Tschicholds books on typography. One of the typographers best ever. For instance he designed Penguin’s original paperbacks. He totally converted me. I have never double spaced since. Read his “the form of the book”
I remember getting docked a trivial point amount my senior year of high school for refusing to double-space after a sentence. . . and that was back in 2004. I still see people double-spacing today, and when I do, I automatically lower my estimate of their IQ by 15.
Mark, like you I was taught typing on a manual typewriter & recall with great clarity getting points deducted on timed exercises whenever I only single spaced between sentences. To this day I correct draft letters done by those that report to me if they only have one space. I suspected that the ‘one space movement’ was another shortcut initiated by those that avoid human contact at all costs; i.e., those that are addidicted to text messaging.
I was always taught 2 spaces. This confounds me. Have I been taught wrong? Have I really been doing this wrong all along? This will be hard to unlearn if that’s the truth. I’m even double-spacing this comment. Argh, so confused!
Let me join the chorus: I was taught to use two spaces on a mechanical typewriter. I saw some blog post that made this single-space assertion a year back and tried using one space afterwards, but it didn’t stick. My fingers are just trained to do two spaces, doubt I can change now. However, most writing is done for the web these days and most blogging software just drops anything more than one space, whether it’s after a period or not. Here’s a test showing that:
1 space after this sentence. Does it work?
2 spaces after this one. Don’t think it will.
Yep, the software inserts two spaces in the second one, but since web browsers ignore anything more than one space- unless it’s specially formatted to show both spaces, which this blog software doesn’t do- there is no difference between how the two sentences are displayed. So do whatever you want, web browsers will just ignore your second space most of the time.
I learned to type in on a manual typewriter several decades ago and I use two spaces after periods. I will continue to use two spaces. I also use two spaces after colons and between state abbreviations and zip codes in addresses.
Same as JT above. I learned to type on a manual typewriter in the mid-60′s, and it’s too late to change now. The high priestess of typography can have her funk.
I still have and use occasionally my IBM Selectric electric typewriter with the changeable typeballs, and love it.
Good typography demands more space between sentences than between an initial and a last name, as in “B. Obama”, which is why double spacing makes sense, even if it is occasionally defeated by software that ignores it. Not obeying in a line that whose spaces are stretched to fill it makes the point clear, if both types of periods occur.
I was taught two spaces, and I LIKE two spaces. It better marks the end of a sentence for a fast reader.
But it does cause problems with some computer formats, resulting in a space in the front of a line (if the previous line ended with a period, space, space).
Reluctantly I likely will try to covert to the single period. Hard for us geezers to change. But I’m thinking about buying a cell phone one of these days, so I guess anything is possible.
That’s “singe SPACE,” not “single period.”
Where’s the damn spellchecker??
I read the article as this is news to me. I was taught the 2-space and it is so automatic it’ll be hard to stop. Still, it’s hard to think the 1-space and salad fork on the left rules are the same level of importance as putting girl’s shirt buttons on the left which has added so much joy to my life as I’ve driven them around. Please don’t change that rule. Ooops! 2-spaces everywhere. Sorry.
I learned in typing class long ago to type two spaces at the end of a sentence, too. But now that I am writing, I’ve been told that most publishers want only one space, and they will be unhappy if they have to fix all my extra spaces. So, I am doing my best to change.
Its no big deal.
It’s amazing to me that people can be passionate about this issue. I learned two spaces, but it’s incredibly unimportant. It’s not like it interferes with communication. It is only an aesthetic. Perhaps we should insist on alternating spacing between each sentence. That would be a more clear signal of… something.
I too use the two spaces after a period, same as everyone who learned on a manual typewriter. Note that the iPhone has a setting that allows you to automatically insert a period and two spaces whenever you hit the space bar twice.