Explanation of the dash

This explanation of the dash in the English language is pretty cool. I wanted to share it with you all.

A dash is a punctuation mark that is similar to a hyphen or minus sign but that differs from both of these symbols primarily in length and function. The most common versions of the dash are the en dash (–) and the em dash (—), named for the length of a typeface’s lower-case n and upper-case M respectively.
Usage varies both within English and in other languages, but the usual convention in printed English text is:
Either version may be used to denote a break in a sentence or to set off parenthetical statements, although writers are generally cautioned to use a single form consistently within their work. In this function, en dashes are used with spaces and em dashes are used without them:[1]
[Em dash: In matters of grave importance, style—not sincerity—is the vital thing.
[En dash: In matters of grave importance, style – not sincerity – is the vital thing.
The en dash (but not the em dash) is also used to indicate spans or differentiation, where it may be considered to replace “and” or “to” (but not “to” in the phrase “from … to …”):[2]
The French and Indian War (1754–1763) was fought in western Pennsylvania and along the present US–Canadian border (Edwards, pp. 81–101).
The em dash (but not the en dash) is also used to set off the sources of quotes:
In matters of grave importance, style, not sincerity, is the vital thing. — Oscar Wilde
Also:
When we combine two or more words to form compound adjectives ahead of a noun, we must use hyphens between them. For example:
“I bought a 60-inch flat screen TV for my living room.”

“The TV I bought for my living room is 60 inches wide.”
“In this demo, the tooltip text size is increased to 35 pixels.”

“In this demo, there is a 35-pixel tooltip text size requirement.” [ignore the tech lingo of this sentence; it was adjusted to illustrate hyphen usage]