The Hyphen, the Em Dash and the En Dash

If you think all dashes and hyphens are interchangeable, you’re mistaken, my friend—sadly mistaken. You need to learn yesterday about the differences among these marks of punctuation. I’m here today to tell you about how to use the hyphen, the en dash and the em dash.

The hyphen (-) is the easy one. It’s the short dash you make with one stroke of your keyboard. The hyphen appears at the end of a line of text when the last word stretches beyond that line. You would also use a hyphen for compound adjectives, especially before a noun. Examples of this include “state-of-the-art cattle prod,” “93-year-old mime” or “post-orchiectomy.” You would also use a hyphen in a hyphenated last name, like Manigault-Newman.

An em dash (—) is the longest dash. You can keep this and the en dash straight because an m is wider than an n and so an em dash is wider than an en dash. You would use this mostly to separate one clause from another in a dramatic way, sometimes without a conjunction, or to join two separate sentences. For example, “He swallowed the poison—and died.” You’d also use an em dash as an appositive when the sentence already contains serial commas. For example, “The colors of the American flag—red, white and blue—are exceedingly lovely.”

On a Mac, make an em dash by pressing shift+option+hyphen. I guess on a PC, it would be shift+alt+hyphen. You can also type two hyphens on a PC and after you skip a space, the hyphens become an em dash. Should you use a space before or after an em dash? I don’t know if there’s a rule but I think it looks better with no space on either side.

It is exceedingly important—pay attention to this—that you never use a hyphen to join two clauses. This looks awful: “Hyphen use in this case is wrong- dead wrong.” See how bad that looks? I read an article by a copy editor describing her job and it used hyphens instead of em dashes throughout. If the editor did it, I’m sure it was embarrassing for the writer. If the writer did it herself, she’s not a very good copy editor.

The en dash (­–) is a little tricky and it’s one diacritic I never used much until recently. Use an en dash for a range of numbers, like “Class, your assignment is to read The Art of the Deal pages 2–37.” Also use it for a sports score, like “The Eagles beat the Patriots, 45–2.” An en dash is also appropriate to separate two destinations, like “Mumbai–Poughkeepsie flight” or when two separate names come together temporarily in opposition or partnership, like “Palin–Hawking astrophysics debate.” This is different from (or is it different than?) when one person has a hyphenated name, which is—get this—hyphenated. I’ve seen some publications use en dashes for compound adjectives but it doesn’t look right to me.

Type an en dash on a Mac by hitting option+hyphen. I don’t know how to do this on a PC without searching for special characters or those number pad codes nobody really uses. Is it just option+hyphen?

OK, wanna read an example of a hyphen, em dash and en dash in one sentence? “The Strunk–White award for Best-Written Lecture About The Relative Values And Uses Of Barely Distinguishable Horizontal Lines Of Type—an award now in its 45^th year, and voted on by an esteemed panel of Pulitzer-Prize winning writers—has been awarded to Brian McCurdy by a score of 673–4.”

Any hyphen/dash dorks feel free to correct me on the preceding, but I’m pretty arrogant in my self-assurance.