Although the difference between dashes and hyphens may not seem to fit neatly under the heading of grammar or word use, the Grammar Owl and I are in agreement that formatting is very important when creating a manuscript, and learning the difference between dashes and hyphens is part of that.
They’re just little lines, aren’t they? What’s the diff which is used?
They are indeed little lines, but they differ in length and in purpose. Whether you’re submitting your manuscript for consideration by agents and/or publishers, or you’re self/independently publishing, using the appropriate little line at the appropriate time helps to make your manuscript look professional.
There are actually three types of those little lines: the hyphen, the en dash, and the em dash.
Hyphens are the shortest, the most common, and are the ones we learn about early in our schooling. They are used to join two (or more) words, such as end-to-end or Smith-Smythe. There are never spaces around hyphens. They like to touch the words or letters they are joining.
As we see from the definition found at the Purdue Owl site (I wonder why the Grammar Owl chose this reference?), hyphens “connect two or more words (and numbers) into a single concept, especially for building adjectives.”
They are used to connect phrases like two-year-old girl, or world-famous opera singer. This tells us that the words must be considered together in modifying the noun that comes after them. You can’t leave out year, and say the two-old girl, and although you could have a locally famous opera singer, you’d not be likely to encounter a world opera singer. So, to show that world and famous are one concept, hyphenate them. (The opera singer will be grateful.)
Hyphens are also used to stand in for the word to, such as writing “the book is intended for ages 9 to 12” as “the book is intended for ages 9–12.” And while we’re on the topic of numbers, they must be used when you’re writing out numbers above twenty: twenty-one, forty-three, ninety-seven.
However, hyphens are NOT dashes. Dashes join two clauses, or set a phrase or clause apart from the rest of the sentence. Dashes like space around them. They don’t like to touch other words the way hyphens do. And dashes are always longer than hyphens.
Because of the way computer programs often automatically create hyphens, it isn’t easy to illustrate the difference in length between dashes and hyphens, but I shall give it the old Owl try. (“Whoooooooooo are you calling old?” I hear from the nearby barn window.)
Hyphens are one short line, touching the words on either side of them. – side-by-side
An en dash is the shorter dash (but still longer than a hyphen). It’s like two hyphens together, and in some computer programs (including some versions of Microsoft Word), to create an en dash, type word space hyphenhyphen space word. If I did that in my version of Word, with regular words and spaces, you wouldn’t see the two hyphens one after the other, you’d see the finished product.
An em dash is a slightly longer dash. It looks like three hyphens stuck together. Just to confuse the issue, some versions of Word, as well as Scrivener, turn two hyphens into the longer dash. Sigh. —
There are rules regarding when to use en dashes and when to use em dashes (of course — there are rules for everything!) I won’t try to list them all here, but I suggest you read this post from the appropriately named Dash Hyphen website for more information.
The Owl and I hope this has helped you understand the difference between hyphens and dashes.
And now, if you’ll excuse us, we must —