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In recent times, to avoid errors, people have been using straight apostrophes and quotation marks. This is acceptable, especially for the Webweb. Just be consistent within a given piece. But whenever possible—especially in print—use the curly or “smart” apostrophe and quotation marks.
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The em dash is the longest of them all, and it’s commonly used to strongly offset a phrase. It should also be used for quote attribution.
Students on the Ithaca campus—especially those who have an interest in art—were delighted to hear about the renovations to the Johnson Museum.
"I love coming back for Reunion." —Jane Smith '10
The en dash is the second-longest, and it is used primarily to indicate ranges.
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