In addition to what @Glorfindel has mentioned about the use of
On a Mac (and on iOS devices connected to a physical keyboard), you
can use ⌥ + - for an en-dash and ⇧
Shift + ⌥ + - for an em-dash.
(⌥ is the Option or Alt key).
On Windows, if you have a numeric keypad, you can use Alt +
0150 resp. Alt + 0151.
There's a great extension ChromeDash that solves this problem gracefully. I find this to be a much better solution then using the cumbersome commands. But note that this only works on Google Chrome.
Simple Instructions of use-case
Simply enter two dashes (hyphens) for an en–dash, and three for an em–dash! This can be changed, as can all other aliases you make!
This works nearly anywhere, in google, hangouts, messenger, facebook, etc.