I still prefer to type two spaces after a sentence-terminating period.
 I am 30 and was taught two.  Apparently with the introduction of
variable-width letters, we are now supposed to use only one.

Am I alone?  How many spaces do most people type?  What do "experts" say?

Howdy, Nelson.

You're certainly not alone. Millions of people have been taught to put
two spaces after a period at the end of a sentence.

I never took typing classes in school. I learned (in the 1950s) from a
book called "Typing Made Simple," which emphasized the importance of
placing one space after a comma and two spaces after a period (or
other sentence-ending punctuation, such as a question mark or
exclamation point). In the days before home word processing and
desktop publishing became common, the norm was two spaces.

I continued to use two spaces well into the 1990s, when I accepted a
job that involved transcribing and summarizing television news
stories. The employer's stylebook specified one space after a period,
and I taught myself to comply (which was not easy: the force of habit
tends to wear ruts in the brain!).

If you prowl around quite a bit online, as I do, you'll find many,
many instances in which two spaces are used after periods. This is
still so common that I doubt that anyone can call it wrong or
substandard. However, most stylebooks these days recommend one space.
Browsers that display text from HTML code typically turn two [or more]
consecutive spaces into one.

"When preparing text-only docs with a monospaced font (e.g. Courier),
it's still a good idea to use two spaces. Otherwise, one space is the
way to go as proportional fonts are designed to use the appropriate
amount of space required by each character."

Channel 9 Forums: Bill Hill - There is only one space after a period 
http://channel9.msdn.com/ShowPost.aspx?PostID=112 

"The use of proportionally spaced type makes two spaces at the end of
a sentence unnecessary (if they ever were). The extra spacing is often
distracting and unattractive. It creates 'holes' in the middle of a
block of text - trapped white space on a smaller scale...

The Bottomline: Professional typesetters, designers, and desktop
publishers should use one space only. Save the double spaces for
typewriting, email, term papers, or personal correspondence. For
everyone else, do whatever makes you feel good."

About Desktop Publishing: Use One Space Between Sentences
http://desktoppub.about.com/cs/typespacing/a/onetwospaces.htm

"How many spaces go after a period?
The current opinion is that one space should be typed after any
punctuation. Many of us learned in typing class that two spaces should
be typed after a period. This convention was used because of nature of
the fixed font of typewriters. Computers, however, usually use
proportional fonts and justification, which create the proper white
space between sentences automatically when one space is typed."

Junket Studies: 11 Rules of Writing
http://www.junketstudies.com/rulesofw/faqs.html 

From the Chicago Manual of Style, one of the most respected
authorities on usage and punctuation:

"The view at CMS is that there is no reason for two spaces after a
period in published work. Some people, however - my colleagues
included - prefer it, relegating this preference to their personal
correspondence and notes. I?ve noticed in old American books printed
in the few decades before and after the turn of the last century (ca.
1870-1930 at least) that there seemed to be a trend in publishing to
use extra space (sometimes quite a bit of it) after periods. And many
people were taught to use that extra space in typing class (I was).
But introducing two spaces after the period causes problems: (1) it is
inefficient, requiring an extra keystroke for every sentence; (2) even
if a program is set to automatically put an extra space after a
period, such automation is never foolproof; (3) there is no proof that
an extra space actually improves readability - as your comment
suggests, it?s probably just a matter of familiarity (Who knows?
perhaps it?s actually more efficient to read with less regard for
sentences as individual units of thought - many centuries ago, for
example in ancient Greece, there were no spaces even between words,
and no punctuation); (4) two spaces are harder to control for than one
in electronic documents (I find that the earmark of a document that
imposes a two-space rule is a smattering of instances of both three
spaces and one space after a period, and two spaces in the middle of
sentences); and (5) two spaces can cause problems with line breaks in
certain programs.

So, in our efficient, modern world, I think there is no room for two
spaces after a period. In the opinion of this particular copyeditor,
this is a good thing."

Chicago Manual of Style: One Space or Two? 
http://www.press.uchicago.edu/Misc/Chicago/cmosfaq/cmosfaq.OneSpaceorTwo.html

Here's an excellent discussion of the one space/two spaces issue:

WebWord: One Versus Two Spaces After a Period
http://www.webword.com/reports/period.html

Another interesting discussion, on a forum devoted to issues related to typography:

Typophile Forums: Double-spacing after periods 
http://www.typophile.com/forums/messages/30/27993.html?1078892522

Google search strategy:

Google Web Search: "one space" "two spaces" "after a period"
://www.google.com/search?hl=en&q=%22one+space%22+%22two+spaces%22+%22after+a+period%22

I hope this is helpful. My own view of the matter is that, since one
space is becoming the new norm, and since it saves a tiny amount of
time and effort, I'll use one space after a period. However, if I see
someone using two spaces, my lip will not curl into a sneer. I reserve
my Billy Idol impersonation for more serious matters. ;-)

Best,
Pink

As always, I appreciate the great research.  Thank you.

You are indeed alone!

And deservedly so ...

Have you not considered the unnecessary waste that results from your actions?

If everybody were so similarly wasteful, it would mean the loss of
another five rain forests, every year.

I see your point. I'll start using a smaller font, too, since that
would use up less RAM and therefore less electricity.

:-)

I was taught to, too  -two-  and still do, because it really is easier
for the eye to recognized the end of a sentence, or to find the
beginning of one when you have glanced away.  And since we do this in
a paperless world, Probo's rain forests remain intact (but they aren't
used to make paper, anyway.  And Sweden has twice as much forest as it
did 100 years ago, and Germany also more than back then, the UK
probably to  - reforestation in Scotland).
Wanted to check what others here do, but will do that later.
Cheers, and remember, it's like being sent to prison:  after one
sentence, you should leave more space before you start the next one.

Nelson,

Thank you very much for the kind words, the five stars, and the nice tip!

~Pink

I learned to type in a typing class on a typewriter. I went to school
to become a graphic designer and learned about typography. Most fonts
on computers are set to use proportional spacing based on the size of
the character, so smaller letters take up less space. The double-space
is automatically taken into account on characters which should end a
sentence on a computer. If you double-space after a period on a
computer, it's technically like putting 4 spaces between sentences.
Some fonts are exceptions to the rule. They are monotype fonts where
every letter is equally spaced. Monotype fonts follow typewriter
rules.

And, yes, when on a typewriter, TWO spaces is correct. When on a
computer, 99% of the time, ONE space is correct.

So, the real question is are you typing an old-fashion typewriter or
are you typing on a computer?

I learned typing on a typewriter in the 80s, so was taught to use two
spaces between sentences.  Some time after that, I heard this rule of
thumb about word processing and proportionally spaced fonts
eliminating the necessity for two spaces and retrained myself to use
only one.  Some time after that, I started grad school and found that
the thesis requirements included following APA style, which is to use
two spaces between sentences, and retrained myself once again.  This
made me look into the subject and it all comes down to 1) personal
preference and 2) the guidelines expected for the situation.  There is
no blanket "right" or "wrong" for all situations, only rules and
guidelines for specific situations.

In terms of personal preference, I have chosen to stick with the
classic approach in most situations.  In addition to two spaces
between sentences, I follow the old rules of two spaces after a colon,
a space between each dot of an ellipsis (even though many word
processing programs autoformat and compress the three individual dots
into a single three-dot character), and most importantly (in my
opinion), I keep the good old serial comma (1, 2, and 3 not 1, 2 and
3).  I have primarily made these choices based on my sense of
readability--I believe that use of an extra space between sentences
and the serial comma ease comprehension and increase reading speed.

For style guidelines, the business, technical, legal, and journalism
worlds usually favor a single space between sentences (and no serial
comma) and the academic and scientific worlds keep the two-space rule.
 It is almost unanimously considered "wrong" in the journalism
community to use either the double-space between sentences or the
serial comma, but I plan to keep using and endorsing both for a long,
long time.

Marcadamianut,
A man (woman?) after my own heart!  Rules of spelling and punctuation
are for pedants who know how but not what they want to express. ;-)
(Any rebutals can only  come fron pedants.  More grins!)
Someone sent me this site, but I am afraid to look at it:

http://owl.english.purdue.edu/

myoarin

And what about the practice of using double quotation marks " rather
than singles '. Think of the rain forests that will continue to stand
proudly if every newspapers, book publishers etc. had a quote quota.

StressedMum, you must be British.  We use double quotes this side of
the pond.  It must be creeping into Jolly Olde England..

Let me say this about that:  "If you are going to write:  'Stressedmum
must be British,' then you should know that there are lots of stressed
mums in the UK, but only one 'Stressedmum', thus you could write: 
'The well-known commenter, "Stressedmum", appears to prefer Birtish
usage.'"
(I know, commas - before or after the Q-marks?  "I did it my way.")

In addition to being stressed I'm also confused because I'm a British
gel gently brought up in the Antipodes so to Brits I sound like Kylie
and to Aussies I sound like, well, Kylie (because she's got an English
accent these days). When it comes to double spaces and single spaces,
I'm in publishing and it's definitely a case of singles in print
nowadays -- I haven't worked on any publication that permits double
spaces after full stops, colons etc. You'll find that many early
publications had a style whereby they actually inserted a space before
any sentence-ending punctuation . (Like that !)

But when it comes to double- and single quotation marks it seems that
no matter what I use, the informed 'others' are using the other. So,
dear nelson it matters not what side of the pond we're on, both sides
(up, down or is that east, west?) are battling it out with singles and
doubles and when there is a result, will someone let me know please?
;)

And dear myoarin, there's also a healthy debate about what is correct
usage of punctuation within or outside quotation marks. I have a style
sheet pro forma which I complete for every publication I work on.
There are several schools of thought on this and so it's easier (and
fiscally necessary) to comply with the client's preferred style rather
than adhere to one style.

I am, however, staging a one-woman battle against the use of
apostrophes to create plurals (e.g. video's, do's). It's rife here in
Australia and I wish our ever-taxing governments (state and federal)
would introduce an apostrophe tax with offenders being fined for
incorrect usage (and a manadatory gaol/jail term for teachers doing it
-- they seem to be the worst offenders!); or the use of an apostrophe
to indicate the possessive in pronouns (e.g. it's instead of its,
your's instead of yours) -- and my particular pet hate, the use of
"your" when what is meant is "you're". When I go out with friends to a
restaurant, they get me to proof read the wine label before we select
it and if there's a typo, we won't get it because we figure if the
wine company is so careless about something as important as their
label, then they mustn't be very careful with the bottle's contents
either!

Cheers

Stressedmum

Stressedmum!
You ain't got no problems like the Germans got:  with apostrophies.
German does not have them for the possessive, but they are starting to
appear all over, wrong usage in German, wrong usage if it were
English.
"Spiegel" magazine (a "Time" - like weekly) has a column on its
website about grammar that hits all the misusage (or is it missusage? 
Looks like the princess of something a nice girl wouldn't want to
volunteer for.).    The column even include a declention or
conjugation table now and then, 'cause the natives don't learn their
language in school any more.

Whatever, you and Archae0pteryx can stick with one space after a full
stop. I still like my two.
And buy "cleanskin" wine and you'll have no trouble with the labels.

And since you're here; what does "yar Orrong" mean?  A street name in
Toorak that someone asked about.

Cheers, and have frosty Foster's for me.  They know that they can't
spell, just 4 Xs on the label.

Myoarin

Uh-oh, tagged me wrong again, Myoarin.  I always type two spaces after
a period, and I will type two spaces forever, just as I have done for
more than four decades.  I don't even try to do otherwise because I
dislike the airless, ill-proportioned look of the single space. 
Programs like FrameMaker that deliver only one space when I type two
are a ceaseless annoyance to me.  So put me down as a confirmed
double-spacer.

Archae0pteryx

I'm glad to see my little question has fostered such discussion. 
Thanks for all your comments!