Hyphen 鈥 Hyphenate compound adjectives only if required for clarity: 鈥渇astest-growing company鈥; 鈥渉igh-level discussion.鈥 Don鈥檛 use hyphens with commonly understood terms, adverbs that end in ly and between figures and units of measure: 鈥済reatly exaggerated claims鈥; 鈥2 percent rule.鈥 Do not use a hyphen with a compound modifier after the noun: 鈥淭he driver was well paid.鈥
Dash 鈥 Dashes set off a series within a phrase: 鈥淥f the many breakfast options 鈥 omelets, waffles, pastries 鈥 he only wanted coffee鈥; indicate a break in thought: 鈥淔elipe鈥檚 is a popular eatery 鈥 in Harvard Square鈥; or attribute a quotation to an author: 鈥溾榊ou must do the thing you think you cannot do.鈥 鈥 Eleanor Roosevelt.鈥 When using text editors that don鈥檛 support dashes, use two hyphens for each dash.
Comma 鈥 Use a comma to set off a person鈥檚 town of residence, age and other such information: 鈥淭om Menino, Boston, was a popular speaker鈥; 鈥淛ean Dupont, 32, was released yesterday.鈥 See Oxford Comma entry for OCU鈥檚 preferred style.
Period 鈥 Use only one space after the end of a sentence. Period.
Colon 鈥 Capitalize the first word after a colon only if it鈥檚 followed by a complete sentence. Colons go outside quotes unless they鈥檙e part of the quoted material.
Apostrophe 鈥 An apostrophe indicates possession. Add an 鈥榮 to all single nouns and names, even if they already end in an s: 鈥淢y boss鈥檚 vacation begins tomorrow.鈥 For singular proper names ending in s, use only an apostrophe: 鈥淜ansas鈥 crisis.鈥 For plurals of a single letter, add an apostrophe and an s: 鈥淢ind your p鈥檚 and q鈥檚,鈥 鈥渢he Oakland A鈥檚.鈥 Do not use apostrophes for decades or acronyms: the 1990s, CDs.
Quotation marks 鈥 Periods and commas go inside quote marks: 鈥溾楻eginald, your hairstyle makes me nervous,鈥 she said.鈥 The position of dashes, semicolons, exclamation and question marks depends on what鈥檚 being questioned or exclaimed: 鈥淲as she right to say, 鈥榊our shoes are a joke鈥?鈥
Parentheses 鈥 AP style suggests avoiding parentheses when possible, and instead rewriting text or using dashes or commas to set off the information. If parentheses are required the rules are: If the parenthetical is a complete, independent sentence, place the period inside the parentheses; if not, the period goes outside.