The Dash

ABRUPT CHANGE: Use dashes to denote an abrupt change in thought in a sentence or an emphatic pause: We will fly to Austin in May – if the convention isn’t cancelled. Fox offered a plan – it was unprecedented – to raise revenues.

SERIES WITHIN A PHRASE: When a phrase that otherwise would be set off by commans contains a series of words that must be separated by commas, use dashes to set off the full phrase: He listed the budget items – advertising, sales and fundraisers – that would be in next year’s budget.

ATTRIBUTION: Use a dash before an author’s or composer’s name at the end of a quotation: “Who steals my purse steals trash.” – Shakespeare.

Don’t confuse them:

• EM dash  — Option + Shift + hyphen
• EN dash – Option + hyphen
• Hyphen - hyphen

Technically, there is only one dash, the EM dash.  However, for design reasons, many people use the EN dash. Put a space on BOTH SIDES of the dash. NEVER use a hyphen when a dash is called for. Never use two consecutive hyphens to indicate a dash.

The Hyphen

AVOID AMBIGUITY: Hyphens are joiners. Use them to avoid ambiguity or to form a single idea from two or more words: The restaurant was famous for its man-eating shark. (As opposed to a man eating shark.)

See AP Stylebook “Punctuation Guide” entryies:

dash and hyphen