Clue in the reader without disrupting the flow (and keep the word count down).

While I was teaching, the phrase “parenthetical information” came up a lot in provincial exams and kids were often confused (but unfortunately I couldn’t give them any help as they filled in their bubble sheet of answers). I tried to include the phrase in a lot of contexts–while direct teaching and while giving one-on-one support–to demonstrate how and why parenthetical information shows up. Writers use parenthetical information, often times with different types of punctuation, to add more information to a sentence to help give context or information to readers instead of writing more sentences (and distracting from the main idea). If the reader takes away the parenthetical information, the sentences should still make sense. And sometimes, if word counts matter, taking out extra information can be one way to decrease the words in a document or assignment.

Ways to include parenthetical information:

• Commas: Writers can include extra information about the topic or subject in the sentence by using a pair of commas to contain the information. This style of punctuation, using two commas, can help keep the flow of the sentence. This style is best used if they information included truly adds a small explanation or bit of information for the reader without taking them away from the intended subject.
• Parentheses: Writers can add information into the sentence by using parentheses. This style is best used if the extra information (included to enhance the understanding for the reader) isn’t directly connected or doesn’t flow with the sentence the information is added into. This style is also more formal, compared to using em dashes.
• Em dashes: Writers can use em dashes if they want the reader to pay more attention to the parenthetical information. The dashes are more punchy, and in-your-face. Writers—who are looking to make more of a splash—use em dashes to create variety, and this style is seen more often in fiction, not so much business writing.

Whatever the mood, whoever the audience, including parenthetical information can add variety to the writing while helping to give your reader more information. And, including parenthetical information means that you get to experiment with different styles of punctuation. Fun!