A grammatical dash —, shown between parts of a compound word or between the syllables of a word when the word is divided at the end of a line of text.

Some people refer to the - as a hyphen or a minus sign.

How dashing the dash is—
So straight and so narrow.
It aims at a word like a spear—or an arrow—
And luckily hasn't a point at one end
Or it might—Just by accident—
Puncture a friend.

But don't call it pointless—it passes for many—
For comma, parentheses—just about any.
It dashes about with the greatest devotion.
It's blunt,
It's abrupt—
It creates a commotion.

It's used to gain emphasis, vigor, a touch
Of surprise—and it's also—by some—
Used too much.