Dash it all!
All about hyphens and dashes
Shutterstock / Robsonphoto / Bitumen road surface with series of white dashes, or lane markings, running diagonally through the centre
Hyphens and dashes always seem to cause confusion in manuscripts. The simple rule is that hyphens are a type of word punctuation and dashes (or rules) are used for sentence punctuation.
Hyphens and dashes are different lengths:
hyphens (-) are the shortest in length
en dashes (–) are roughly the length of a lower-case n or e, or more accurately, half the length of an em dash
em dashes (—) are the length of an upper-case M.
Hyphens are created by using the hyphen/underscore key, which sits to the right of the number zero on a generic keyboard.
En dashes and em dashes can be created in one of three ways:
using the shortcut key combinations of Ctrl+minus (the minus key is found on the numeric keypad just above the + key) for an en dash and Ctrl+Alt+minus for an em dash (on a Mac, use Option+hyphen for an en dash and Option+Shift+hyphen for an em dash)
using the symbol menu, by choosing Insert, Symbol, and then More Symbols (on a Mac, choose Insert, Advanced Symbol, Special Characters)
holding down the Alt key and typing 0150 for an en dash or 0151 for an em dash (no option on a Mac).
As a form of word punctuation, hyphens are used to join words together, or to separate words into syllables.
Use hyphens to:
attach some prefixes (such as “pre-order”) and suffixes (such as “20-odd”)
join some compound words (such as “sister-in-law”)
create compound adjectives (such as “well-paid job”)
break a word between syllables at the end of a line.
Note that not all prefixes, suffixes and compound words require hyphenation. Refer to a dictionary or a style guide to determine when hyphens should be used on a case-by-case basis. The Chicago Manual of Style has a particularly helpful hyphenation table available online.
En dashes and em dashes are types of sentence punctuation. En dashes are generally used to link things together while em dashes are generally used to set things apart.
Use en dashes to:
show ranges of numbers (such as 30–60)
join words to show an association or relationship (such as the “Asia–Pacific region”, or a “cost–benefit analysis”)
join compound adjectives when at least one of the elements being joined is an open compound (such as “Australian Government–backed proposal”).
En dashes may also be used:
as a minus symbol (such as “–5”)
in place of a hyphen when attaching a prefix to more than one word (such as “post–World War II architecture”)
instead of an unspaced em dash (used as a spaced en dash).
Em dashes are generally used for three purposes:
to set apart parenthetic elements of a sentence, usually in place of commas, parentheses or colons (such as “The package arrived—six months after it was ordered—and was left on the front porch.”)
to show emphasis or clarification (such as “The courtroom grew silent as the judgment was read out—guilty as charged.”)
to show a sudden change (such as “I should arrive at 6—no make that 7.”).
Em dashes can be particularly useful in place of commas when the parenthetic element is a list joined by commas (such as “The party—organised by Jane, Peter, Mary and Paul—was talked about for weeks afterwards.”).
On a final note, be aware that the use of hyphens and dashes may differ depending on the style guide being used. For example, the 17th edition of the Chicago Manual of Style specifies en dashes for number ranges, whereas the 11th edition of the American Medical Association Manual of Style specifies hyphens.
Be sure to check the relevant style manual for final guidance on the use of hyphens and dashes.
