The Editor’s Manual
Free learning resource on English grammar, punctuation, usage, and style.
Commas, colons, semicolons, dashes, and other punctuation marks that make you tear your hair out.
Use an apostrophe to form a possessive noun (“the cat’s tail”) or a contraction (“don’t”). Only rarely is an apostrophe used to form a plural (“p’s and q’s”).
A hyphen is a short dash used to connect words and indicate that they together carry a single meaning. It can also signify a missing word, divide a word at the end of a line, or show a range.
An em dash sets off explanatory statements, an en dash signifies a range, and a hyphen connects words. An em dash is longer than an en dash, which in turn is longer than a hyphen.
Use an en dash to show a range (2001–02) or to replace the word “to” (Boston–New York flight). Also use an en dash to show a connection across words (US–Canada border).
Use em dashes to set off parenthetical statements, amplify a thought, begin a sentence with a list or a single noun and then provide an explanatory statement, or to mark asides, interruptions, and sudden turns in thought.
Use a semicolon in place of a period to join two closely related sentences. Also use it to separate list items that themselves contain punctuation.