Board Thread:The Time Lord Academy/@comment-6433721-20130309061324/@comment-188432-20130309183726

Just for clarity on a point made above, dashes in OS X — since at least 10.3 — have been made with.

actually produces two characters, the simple hyphen (–) and the inequality sign (≠).

Of course, it's super easy to set up a Mac to always simply replace -- with —, so that you don't even have to use any special key presses at all. It'll just make the proper em dash (or © or ® or ⅞ or ⅔ or whatever) as you type.