Dashing from Dashes
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I am fond of using dashes in my writing — dash it all, why not?. However, I have tended to become lazy, and to use a hyphen for all purr-pussies. (As in kit-cat?) 🙂
As a professional editor, I should be more meticulous. There is a distinct difference between appearance and usage of a hyphen, an en dash, and an em dash. Here are the rules for each, and I have resolved to stick to them in future.
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The hyphen (-) is found on the top row of the keyboard below the underline. It is used without spaces to join two or more words into one concept such as up-to-date or flower-child.
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n
An en dash (–) has the width of ‘n’; it is obtained by using Ctrl and the minus sign on number keys*; and is primarily used to replace the word ‘to’. Examples: Opening hours 8:00 a.m.–5:00p.m., or ‘The final score was 3–1’ or ‘Trading results were up–down’ (arguable) or ‘From A–Z’. *(Update: or press down Alt while keying 0150 on number keys.)
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m
The em dash (—) has m width; for this you press Ctrl, Alt and minus sign on number keys*; denotes a pause or a different line of thought. Examples: ‘If you keep interrupting, I can’t finish a —’ or ‘How do you do — reminds me, wonder how he did?’ or ‘He spoke confidently — though there was little for him to be confident about — for some time.’ No spaces are necessary before or after, but some writers—including myself—think this non-spaced result is too crowded. Whichever option is chosen should be used consistently. *(Update: or press down Alt while keying 0151 on number keys.)
Final Update: Just to show clearly the actual differences between the em dash, the n dash, and the hyphen, I have superimposed them under letters of the same font. Note the slightly lower level of the hyphen.