A hyphen (-) is used to connect two words that function as a particular concept, or when linked together form a particular modifier. A hyphen is also used to separate syllables of a word when there is a line break, though this was more prevalent when type was set by hand rather than electronically. A hyphen is also used to separate numbers. The word hyphen comes into the English language in the 1620s from the Greek word huphen, meaning together.
An en dash (–) is used when writing about a range of things that are related. For example, when writing about a specific range of years or pages. If one would express the particular punctuation mark as to, as in 1911 to 2011, then use the en dash. The en dash gets its name from the fact that it is as wide as the letter n.
An em dash (—) is used as a substitute for a comma, colon, semi-colon or parentheses. An em dash is mostly used to set apart a phrase or clause. It also may be used to indicate something missing. Sometimes, an em dash is used in the same manner as a bullet point or to show an interruption between two people engaged in a dialogue. The em dash gets its name from the fact that it is as wide as the letter m. In British English, an en dash with spaces before and after the en dash is often used instead of an em dash.
Both conducting and playing were first-rate throughout: the performance undoubtedly benefited from being the third of five on the English Concert’s tour. (The Evening Standard)
For more information, call 816-444-5588. (The Kansas City Star)
He is revered by many for quashing a bloody guerrilla insurgency during his 1990-2000 presidency and turning around an economy in ruins, but is loathed by others for human rights abuses and corruption convictions. (Reuters)
After decades of muttering and grumbling about our new status as part of a great supranational body, we have the chance to decide – once and for all –whether we wish to stay or leave. (The Daily Mail)