The hyphen, the em dash, and the en dash are all easy to confuse. They are all lines used for punctuation, but they vary in length. Many writers mistakenly think they are interchangeable. They serve different purposes, however. The hyphen is the shortest of the three. It primarily serves to separate numbers (account numbers, phone numbers, etc.) and to combine words. For example, two words can be joined by a hyphen to make a compound descriptive word such as brother-in-law o