Punctuation marks are used to signal meaning to the reader. They show emphasis and inflection in writing in place of the verbal pauses and tonal changes in speech. Unfortunately, unlike verbal signals, they are easy to use incorrectly without the writer's (or reader's) notice. Incorrect punctuation can make reading more difficult. In some cases, incorrect punctuation can change meaning.

Below is a review of the basic punctuation marks and their uses. This guide covers the comma, semicolon, colon, parentheses, the hyphen and dash, quotation marks, the ellipsis, apostrophes, capitalization and end punctuation.

 Comma ,

After the period, this is probably the most used punctuation mark. Basically, the comma performs two main functions: 1) It separates items in a horizontal list; 2) It sets off dependent clauses and phrases of various types. For a fuller discussion, see the Quick and Easy Guide to Commas

Example: However, the comma is versatile, and it can be used in lists, clauses, and phrases.

 Semicolon ;

The semicolon really only has two proper uses. First, it joins related independent clauses in compound sentences (without a conjunction). Second, it is used to separate items in a series that include punctuation. The semicolon is NOT used interchangeably with the comma.

Example: It seemed that it would last forever; it didn't.

Example: The world leaders participating in the talks included George Bush, President of the United States of America; Tony Blair, Prime Minister of the United Kingdom; and Hu Jintao, President of the People's Republic of China.

 Colon :

A colon is used after a complete statement to introduce one or more directly related ideas, including lists, quotations, directions or other comments detailing the statement. It is NOT correct to use the colon with an incomplete phrase. The colon is also used to punctuate business salutations and time of day in numeric form.

Example: Mount Rushmore features the faces of four presidents: Washington, Jefferson, Lincoln and Theodore Roosevelt.

Example: The recent poll taken of our students proves one thing: they don't like lecture courses before 7:30 a.m.

Example: Dear Mrs. Jones:

 Parentheses ()

Parentheses, always used in pairs, set off non-essential or tangential material included in a sentence including examples, dates, sources, or subordinate ideas.

Example: We always celebrated my great-grandfather's birthday (September 29th) as though he were still with us.

 Hyphen - and Dash --

The hyphen and the dash are separate and distinct markings. Technically, the hyphen is not punctuation but part of a word. The hyphen and dash may NOT be used interchangeably.

A hyphen is used to create compound words and to break up a single word at the end of a sentence. In the latter case, words should be divided between syllables or between compound words. Single syllable words should NOT be divided. Also, divided words should not end a line with a single letter or begin a line with less than three letters.

Example: Despite my brother-in-law's complaints, I always enjoyed Williamsburg for its authentic re-creation of frontier-
village life.

The dash is used to set off and emphasize an explanatory comment or detail. A colon or parentheses may also be used for this function, but with less emphasis. Depending on your word processor, the dash is either a single line longer than a hyphen or created by joining two hyphens.

Example: The true meaning of the message -- love conquers all -- remains a central theme throughout the piece.

 Quotation Marks " "

Quotations marks are used to enclose direct quotes, with commas and periods inside the closing quotation mark. Colons and semicolons go outside the quotation marks. Question and exclamation marks are enclosed if they are part of the quoted material. Quotation marks can also be used to indicate special usage of a term or irony.

Example: "All I want to know," she asked, "is why we are here?"

Example: I don't know how much more "progress" I can stand.

 Ellipsis . . .

Made of three spaced periods, the ellipsis indicates deleted words in a quotation or to suggest unfinished thoughts.

Example: The report stated that "measurements taken under controlled conditions . . . provided for more accurate data collection."

 Apostrophe '

The apostrophe is primarily used to show possession, to denote contractions, and to pluralize numerals and letters. In the case of possessive forms, the following rules apply:

• Add an 's for nouns that do not end in s, or singular nouns that end in s.
• Add an ' for nouns that are plural and end in s.
• For joint possession or compound nouns, add the ' (with or without the s) with the last element only.
• Use the 's with indefinite pronouns (everyone's, someone's, anyone's, something's), but not with definite pronouns (its, whose, his, hers, ours, yours, theirs)

Example: John and Lois's claim wasn't relevant in the 1980's. An idea like theirs wouldn't matter until much later.

 Capitalization

Capital letters are used to signal proper names (people and organizations), words beginning a sentence, and major words in titles and subtitles. Capitals letters are also used with quotes UNLESS the quote is blended into the sentence. Capital letters should NOT be used for common nouns, words after a colon (unless an independent clause - then it is optional), or blended quotes.

Example: "The XYZ movement," John exclaimed,"is out of control! Citizens of the United States must act now!"

 End Punctuation .?!

End punctuation does just that, it ends a sentence. The period is used to end all sentences except those denoting a question or exclamation. The question mark denotes a question, either direct or rhetorical. The exclamation point denotes excitement or emphasis. It also sets off interjections.

Example: Hey! What are you doing?