As an editor, it’s my job to be fastidious. As a content writer, I understand the all-too-familiar scenario of clenched fists over a keyboard and a jaw line tightened in frustration while trying to decide whether to use a comma or a dash. While many people don’t think twice about the length of a horizontal punctuation mark, it’s my job to notice everything that graces the pages of our content at CEM.

Over the years, I’ve glared at my computer screen countless times while repetitiously inserting and deleting a comma, only to insert it again, then second guess whether or not an em dash would have done the trick. Dashes can be thorny creatures, but when used correctly, they give your content a mark of distinction.

En Dashes Work with Numbers

Named for its length, which was equivalent to the letter “N” during the years of letterpresses and lead, the en dash is slightly longer than a hyphen, and it’s typically used to connect numbers. Usually, an en dash represents a numerical range such as “up to and including,” “through,” and sometimes “to.” The following sentences use en dashes:

In the guide, pages 114–213 cover the most important topics.

The years she spent in Boston, 2004–2010, marked the highlight of her career.

In 2011, the Ravens beat the Steelers 35–7.

An en dash doesn’t have its own key on a regular keyboard like its cousin, the hyphen. Different word processing programs use different functions, but usually option + hyphen will create an en dash. If that doesn’t work, you can use the special characters function.

The Dashing Em Dash

The em dash, longer than the en dash, and named for its length equivalent to the letter “M,” is mainly used to indicate an abrupt change in a sentence or a series within a sentence. It’s versatile in its function, as it can be used to replace commas, colons, semicolons, and even periods. Many editors claim the em dash is overused, and I’d have to agree, but that’s not to say I’m not fond of it. Em dashes glide smoothly from word to word, and indicate, in my opinion, a welcoming pause in sentence flow that usually creates grace and clarity with a text. Examine the following sentences:

There is one detail of human existence that the populace has underestimated throughout history—the power of writing.

There is one detail of human existence that the populace has underestimated throughout history: the power of writing.

Both sentences are grammatically correct, but as Ben Yagoda notes in an article for the New York Times, sentences using a perfectly positioned em dashes “seem to live and breathe, while the others just lie there on the page.”

Unfortunately, the em dash doesn’t have a key dedicated for its purpose on a standard keyboard. Most word processing programs insert an em dash in place of two consecutive hyphens. On a Mac, option + shift + hyphen will create an em dash. Again, you can also use the special characters function.

Traditionally, an em dash is used without preceding or following spaces, but the rules have become flexible with the growth of the internet, and this is where things get a bit dicey. Depending on the type of web design being used, em dashes can become eyesores because they cause rigid line breaks, especially when used in a narrow side column of a layout. Many editors are opting for en dashes with spaces on either side in place of an em dash, and I can’t argue that it’s not aesthetically superior for web content.