What is an En Dash?
An en dash (–) is a punctuation mark that is wider than a hyphen (-) but narrower than an em dash (—). It gets its name because typically the en dash is similar in length to the letter N and the em dash is similar in length to the letter M.
Many writers neglect the N dash and only use a hyphen or an em dash. This is especially likely to happen online because a typical keyboard doesn’t have a dedicated key for it. However, there are certain situations in which the en dash, and not any other punctuation mark, should be used.