Punctuation

Overview

Web punctuation supports brevity, rhythm, and user focus in the following ways:

• Helps readers scan and navigate content.
• Prevents misunderstandings.
• Adds tone and personality.
• Improves accessibility and screen reader interpretation.
• Keeps the content feeling professional and polished.

Punctuation guidance

Refer to the following guidance for punctuation in your writing.

Dashes

• Do not use dashes between date, age, or time ranges. Instead, use "to."
• Example: 4 to 5 p.m.; not 4—5 p.m.

Em-dash

• Use an em-dash (long dash, width of the letter M) with no spaces on either side (—) in the following cases:
• To denote an abrupt change in thought or an emphatic phrase. Avoid overuse of dashes to set off phrases if commas will suffice.
• Example: Throughout her long reign, the queen and her family have adapted—usually skillfully—to the changing tastes of the time.
• When a phrase that otherwise would be set off by commas contains a series of words that must be separated by commas.
• Example: He listed the qualities—intelligence, humor, conservatism, independence—that he liked in an executive.
• Before an author's name at the end of a quotation
• Example: "Who steals my purse steals trash."—Shakespeare.
• In datelines
• Example: NEW YORK (AP)—The city is broke.

En-dash

• Use an en-dash (medium-length dash, longer than a hyphen/shorter than an em-dash, width of the letter N) with no spaces on either sides (–) in the following instances:
• To modify a hyphenated or compound-word term
• Example: He understands the challenges non–English-speaking patients face. The diagnosis was estrogen receptor–negative breast cancer.
• To indicate subcategories of an entity
• Example: HUP–Cedar; Department of Otolaryngology–Head and Neck Surgery
• Compound adjectives in which a set of adjectives collectively describes a single noun should be grouped with hyphens. Hyphenate the adjectives that must be combined with each other to make meaning as a single term. (e.g., “low-molecular-weight heparin,” “low-birth-weight babies,” “High-cost multi-drug infusion regimens”)

Commas

• Use a final (serial/Oxford) comma before the conjunction in a series.
• Example: The flag is red, white, and blue.
• Example: She was living with type 2 diabetes, cardiac disease, high blood pressure, and osteoporosis.
• Do not use commas to separate a series of adjectives unless it is appropriate to the intended meaning of the phrase to insert the word “and” where the comma appears.
• Example: He pressed the big red button.

Semicolons

• Use a semicolon to clarify a series that includes several commas or uses of “and” and “or” to avoid confusion.
• Example: His doctor said to monitor his blood pressure and cholesterol; weight and dietary restrictions; and medications and supplements.
• Example: On hand for the ceremony were Kara Smith, MD, president; Sam Jones, MSN, BSN, vice president; and Julie Miller, MD, PhD, treasurer

Colons

• Capitalize the first word after a colon only if it is a proper noun or the start of a complete sentence. This applies to headings as well.
• Example: The procedure involves three steps: mixing, incubating and analyzing the samples.
• Example: Neuro-orthopaedic excellence: what sets us apart

Quotation marks

• Always use smart (curly) quotation marks.
• Place commas and periods inside of quotation marks.
• Example: “I hope the tooth fairy brings me a race car,” said the little boy.
• Example: According to the dean, “This academic year has been a challenging one.”
• Place exclamation points and question marks inside quotation marks if the quotation itself is an exclamation or question, but outside if they are the ending of the full sentence in which a non-questioning/non-exclamatory quotation appears.
• Example: She asked, “Who left the dishes in the sink?”
• Example: Which civil rights leader coined the phrase “good trouble”?
• All other punctuation marks are placed outside quotation marks.

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