Punctuation

Periods and spaces

Use only one space after all periods and between sentences.
With a series of middle name initials, do not use spaces between the periods.
Example: Anna M.R. Brown

Colons

Use a colon to introduce a bulleted list when using paragraph formatting. When a heading (h2, etc.) introduces a bulleted list, there is no need for the colon.

Semicolons

Semicolons join two complete independent clauses.
Example: The book is finished; production starts next week.

Semicolons separate phrases that contain commas.
Example: The cover will be red, white, and blue; green, blue, and yellow; or blue and white.

Use a semicolon instead of a comma when each component is lengthy or contains a comma.
Example: The college will add a master’s program, open only to alumni; a doctoral program, open to all candidates; and a post-master’s certificate program.

Commas

Use commas:

To separate the terms in a series. There should be one more component than there are commas.
Example: red, white, and blue
Example: June, July, or August

To enclose parenthetic expressions
Example: The report, previously compiled once a year, will soon be available every month.

Before a conjunction that introduces an independent clause
Example: Most of the new system is installed, but the printer isn’t connected yet.

In a string of adjectives to call attention to each
Example: They replaced the old, noisy, slow printer.

After a long introductory phrase before the subject of the sentence
Example: Knowing the readers are not technical experts, the writers do not use jargon.

To contrast elements in a sentence
Example: They need to add people to the testing team, not push back the schedule or eliminate testing.

In specifying academic degrees of alumni (between the name and the degree) and in separating multiple class years.
Note that the comma isn't needed when a single class year is used.
Example: Jane Doe, JD '16; Julie Doe '12, MFA '16; John Doe '90, '12. No comma here: Jane Doe '16.

Do not use commas:

Before Jr., Sr., etc., in names: John Smith Jr.

To break up long groups of words
Incorrect: You can press the ESC, to return to the menu, and not save your changes.

To set off restrictive modifiers. If the modifier is necessary, do not break it off with commas.
Correct: People who live in glass houses shouldn’t throw stones. (necessary, so no commas)

Between a conjunction and the work it introduces
Incorrect: We need a new printer but, we can’t get funding.
Correct: We need a new printer, but we can’t get funding.

Apostrophes

Use apostrophes with nouns to show possession.
Singular nouns: user’s response, witness's account, state's administrative rules, 2003's legislative measures, SEIU's negotiators

Use apostrophes with singular nouns ending in s. However, the final s is usually omitted when it is silent in speech: for goodness’ sake
Plural nouns: writers’ computers, children’s website

For plural nouns ending in s, use an apostrophe only after the s: artists’ designs
Be careful not to confuse possessive pronouns, which do not take apostrophes, with contractions, which do.

Possessive pronouns: its, whose, our
Contractions: it’s, who’s

Correct: OCPF revised its administrative rules. (Belonging to OCPF)
Correct: It’s on the web. (It is on the web)

Omit the apostrophe from plurals that are not possessive.
Example: Things changed in the 1990s.
Example: All SOPs are on the web.

Ellipses

Use three dots (an ellipsis) to indicate the omission of a word, phrase, line, or paragraph in a quote. Use spaces before, between, and after the three dots.
Example: All documents, files . . . and related materials must be updated.

Use three dots followed by a period if words have been omitted at the end of a quoted sentence.

Quotation marks and italics

Limit the use of quotation marks to set off terms.
Example: The term planned giving does not need to be enclosed in quotation marks.

Period and commas go inside the closing quotation mark.
Example: For information on this topic, refer to “Editing Standards and Guidelines.”

Semicolons and colons go outside the closing quotation mark.
Example: I read the second article, “Why we write”; I didn’t have time to read the next one.

A question mark or an exclamation point goes inside the closing quotation mark when it applies only to the quoted material.
Example: His first question was, “How do I use this?”
Example: Stop saying “Don’t worry”!

Italicize the names of books, films, plays, newspapers, journals, television shows, and boats. Use italics for foreign words and phrases.

Use quotation marks around the names of articles, chapters, lecture titles, and titles of television show episodes.
Example: She graduated magna cum laude.

On web pages, limit the use of italics because it is difficult to read on the screen. Use boldface for emphasis, but try to be restrained in using it.
Excessive italics: Do not arrive on campus before the time stated in this schedule.
Better: Do not arrive on campus before the time stated in this schedule.

Exclamation point

Avoid using exclamation points on web pages.

Hyphens

Use a hyphen:

With prefixes, before a proper noun or number
Example: pre-1985, post-Olympics

For clarity
Examples: re-cover is not the same as recover; re-create is not the same as recreate

With all-, cross-, ex-, self-, half-, quarter-
Examples: all-inclusive, self-indexing, cross-reference

When forming compound words, hyphenate:

Compound modifiers before a noun
Examples: stock-market prices, foreign-made product

Compound numbers less than one hundred
Examples: sixty-eight, two-thirds, fifty-one, two hundred

Adjective-adverb combinations
Examples: best-selling book, well-known company

Phrases used as adjectives
Examples: state-of-the-art system, 100-page-per-minute printer

Numbers before a unit of measure and a noun
Examples: 11-inch paper, half-million-byte increments

Noun-participle combinations
Example: self-training course

When forming compound words, do not hyphenate:

Compound modifiers if the first word ends in “ly”
Examples: easily learned program, hastily called meeting

Adverb-adjective combinations when the adverb can’t be misread as an adjective
Examples: more common command, high level language

Dashes

The three types of dashes, from shortest to longest, are hyphen, en dash (or minus sign), and em dash.

En dash means "to" or "through."
Examples: 1900–2000, 30–40

The minus sign is an en dash, the same width as other arithmetic operators (available as special characters in T4).
Examples: –4

The em dash indicates a break in thought. (Available as a special character in T4, or use two hyphens with no space before or after.)
Example: An indicator—a flashing light or an alarm—signals danger.

Hyphens and dashes

When to use a hyphen? When to use a dash?

The hyphen is used to combine words (well-being, advanced-level) and to separate numbers, such as Social Security numbers (010-00-0001). On the keyboard, the hyphen is between the 0 key and the key for the = sign.

Note: Hyphens used to break up words from one line to the next are unnecessary on the web. If your text document hyphenates words between lines, be sure to clean up the hyphens before you publish the same text on the web.

The em dash is what we typically think of as a "dash" in punctuation. It usually indicates a strong break in a sentence. An em dash can be used to detach the end of the sentence from the main body. Em dashes can also be used—often to good effect—in pairs to set off parenthetical material.

When we use a single hyphen in place of the em dash (or two hyphens), it makes the text hard to understand.

Don't: I have my favorites-vanilla, coffee, chocolate.
Do: I have my favorites--vanilla, coffee, chocolate.
Do: (better) I have my favorites—vanilla, coffee, chocolate.

Create the em dash

Mac keyboard: option + shift + hyphen
PC keyboard: alt + shift + hyphen

The en dash means "to" or "through," and it's commonly used to indicate inclusive dates and other numbers: Dec. 23–Jan. 6, pp. 32–44. (Note no space before or after the en dash.) The en dash is longer than a hyphen and shorter than an em dash. Because it's not available on a keyboard, the en dash is often indicated by a single hyphen with a space before and after: Dec. 23 - Jan. 6, pp. 32 - 44. That's acceptable, but T4 also provides the en dash as a special character.

Don't: Dec. 23-Jan. 6 (hyphen with no spaces)
Do: Dec. 23 - Jan. 6 (hyphen with spaces before and after)
Do: (better) Dec. 23–Jan. 6 (select en dash from special characters menu)

Create the en dash

Mac keyboard: option + hyphen
PC keyboard: alt + hyphen

Fun fact: Em dashes and en dashes were once available only to professional printers. The em dash was equivalent to the width of a typesetter's M; the en dash was equivalent to the slightly more narrow N.