Correct punctuation can help your writing in communicating the intended meaning, emotions, and actions. From what you read every day, you have seen small dashes in words [-] and big ones in sentences [—]. We want to elucidate hyphens’ and dashes’ uses and differences to help keep your meaning clear and your punctuation under control.
-Hyphen- (the minus key next to 0 or on numeric key pad)
1. Used in compound words to clarify meaning. Because the hyphen connects words to show they relate, they are often used with adjectives before nouns to keep the meaning clear. What is the difference between a small animal hospital and a small-animal hospital? The first says the small hospital is for animals, the second that the hospital is for small animals, which is differentiated because of the hyphen (example from Chicago 6.80–6.94).
2. Used in writing out numbers. Fifty-three twelve-year-olds went to the small-animal hospital.
–En Dash–(This is longer than a hyphen, but shorter than an em dash; on a Mac: Option + -; on a PC: CTRL + -)
1. Used for inclusive numbers. What are those? Dates and page numbers and such. I went to school 2006–2007. Please read pages 6–21.
2. Means “to” or “through.” However, if the sentence uses “from,” don’t use the en dash for the “to.” BYU beat U of U 21–7. From chapter one to chapter three, she used the em dash correctly. Incorrect: From chapter 1–3…
—Em Dash—(On a Mac: Command + Shift + -; on a PC: CTRL + ALT + -; or type a word, two hyphens, and next word, with no spaces)
1. Used for interjections—it interrupts the sentence. When two em dashes are used in a sentence, they are a stronger interruption than commas, but also more informal. If—this has happened before—you use this too much, it loses—heaven forbid—much of its effect. Using more than two em dashes in a sentence muddles the sentence, so stay away from it.
2. Sets off a definition or list; amplifies or explains. To be or not to be—that was the question, wasn’t it?
These may seem somewhat subtle, but using them correctly can help readers understand what you mean without second guessing.