Grammar Girl here.

Today's topic is dashes.

Scott from the Twentyhood podcast; David from Cliffside Park, New Jersey; Cade, who is a recent communication design graduate; and listeners named Josh and Matt all asked about dashes in the last few months. But what really pushed me over the edge to choose this topic was a question from Jeff in Centerville, Virginia. Jeff listened to the last episode about colons and then asked if it would be OK to use a dash instead of a colon in the example sentence. The example was "Grammar Girl has two favorite Thanksgiving dishes: green-bean casserole and stuffing," and yes, Jeff, you could definitely replace the colon in that sentence with a dash.

The difference between a colon and a dash is really subtle: they can both serve to introduce a related element after the sentence, but a dash is a stronger and more informal mark than a colon. Think of a colon as part of the sentence that just ambles along. "Grammar Girl has two favorite Thanksgiving dishes [and, now I'm going to tell you what they are, colon] green-bean casserole and stuffing." A colon informs readers that something more is coming along.

A dash, on the other hand—well, it's quite a dramatic thing. A dashing young man is certainly not an ordinary young man, and if you're dashing off to the store, you're not just going to the store, you're going in a flurry. A dash interrupts the flow of the sentence and tells the reader to get ready for some important or dramatic statement. If you added a dash to the Thanksgiving sentence it would conceptually read something like this: "Grammar Girl has two favorite Thanksgiving dishes [wait for it; wait for it; dash] green-bean casserole and stuffing." Wow!

Given that there isn't really anything exciting about my favorite dishes, a dash might not be the best choice here, but it wouldn't be wrong. It would be a better choice if that sentence were part of a mystery novel where green bean casserole was missing, and Grammar Girl was implicated as the thief. Then it could be a dramatic announcement that I love green-bean casserole, and a dash would make more sense.

And here's a very important rule about dashes: never, never, never use a hyphen in place of a dash. A hyphen is not a junior dash; it has its own completely separate use that I'll talk about at some point in the future, but I can't talk about dashes without telling you not to use hyphens when you should use dashes. If for some reason you can't insert the dash symbol, use two hyphens right next to each other: hyphen hyphen [--]. You'll save an editor or typesetter from having a mild fit. I feel bad because I've lost track of the name, but one listener wrote in to say that he or she actually feels a little ill when confronted with a hyphen used as a dash.

Also, you may have heard of two different kinds of dashes: em dashes and en dashes. An em dash is longer than an en dash. Those might seem like strange names, but they make sense when you realize that the em dash is as long as the typeset letter M and the en dash is as long as the typeset letter N.

The em dash is the kind of dash I was talking about before; it is the kind of dash you use in a sentence (1). When people say, “Use a dash,” they almost always mean the em dash.

The en dash is used much less frequently and usually only to indicate a range of inclusive numbers. You would use an en dash to write something like Squiggly will be on vacation December 2 to December 9, where the to between the dates is an en dash and indicates that Squiggly will not be in the office starting the 2^nd of December and will return on the 10^th of December (because an en dash indicates that the numbers are inclusive of those two dates).

Whether you are using the longer em dash in a sentence or the shorter en dash to indicate an inclusive range, there are no spaces between the dash and the words around it. This is actually a style issue, so you should consult a style guide if your company or teacher has one, but I recommend using no spaces.

There's even more to say about dashes, but I'll save that for another day. Also, I just noticed that my word processor automatically inserts an en dash when I type two hyphens. Arggg. The horror! I've read in some places that newspapers or certain typographers prefer en dashes because they are shorter (2,3), so this could be a style issue, but in general most style guides call for the longer em dash (4,5,6), and I think the word processor is just wrong! Be warned that you may have to fight your computer on this one.

That's all. As always, this is Grammar Girl. I have another book to give away. This time the winner is Aileen S., and I'll be mailing out her book, The Pinocchio Intermediate Vocabulary Builder by Mark Phillips, this week. This book is similar to the last one in that Mark took the book Pinocchio, which is in the public domain, and adapted it to include a bunch of words that people study for the scholastic aptitude test (also called the SAT). So you get to read the story of Pinocchio and learn the words in context along the way, and all the words are defined on the page where they are used. So again, it's a really clever concept, and thanks to Mark Phillips for donating the book, which will also be available for sale on the Grammar Girl web site at quickanddirtytips.com.

I have two more books from Mark Phillips to give away, so you can all look forward to that, and if there are any publishers out there who want to donate books that I can give away, please e-mail me at feedback@quickanddirtytips.com or call the voicemail line at 206-338-GIRL (4475). I won't give away just any random book, but if you have something you think Grammar Girl listeners would truly enjoy, then I'd be happy to do a giveaway.

Finally, you can find a complete transcript of this podcast at the Grammar Girl section of QuickAndDirtyTips.com. Also, thank you to Steve Thornton from British Columbia for help on preparing the transcript for this episode.

References

1. The Chicago Manual of Style. Fourteenth edition. Chicago: University of Chicago Press, 1993, p. 5, p. 107.
2. Wikipedia contributors. "Dash." Wikipedia, The Free Encyclopedia, November 27, 2006 <http://en.wikipedia.org/w/index.php?title=Dash&oldid=90376898> (accessed November 29, 2006).
3. Sheerin, P. K. The Trouble With EM ’n EN (and Other Shady Characters), October 19, 2001 <http://alistapart.com/articles/emen/> (accessed November 29, 2006).
4.  Faigley, L. The Little Penguin Handbook. New York: Pearson Education, 2006, p. 233.
5.  Aaron, J. E. The Little, Brown Essential Handbook. Fifth edition. New York: Pearson Education, 2006, p. 84.
6. The Chicago Manual of Style. Fourteenth edition. Chicago: University of Chicago Press, 1993, p. 5, p. 105.