Nuts and mutton

An en dash is used to connect two things or denote a range, for example dates (13–14 June), places (Sydney–Hobart) and pages (22–33). An en dash is approximately the width of a lowercase n, and is also referred to as a nut dash. An em dash indicates a transition — or added emphasis — within a sentence — or an afterthought. An em dash can replace commas, semicolons, colons and parentheses to indicate an interruption or change of thought. An em dash is approximately the width of an uppercase M and is also known as a mutton dash.