Colon, Semicolon, and Em Dash
June 23rd, 2026
Bellevue, WA
Whenever I'm using AI for content, em dashes show up everywhere. I realized I avoid them in my own writing mostly because I never learned the rules. So here's a short reference for all three — colon, semicolon, and em dash — so I actually know what I'm doing next time.
Photo by Patrick Fore on Unsplash
Colon (:)
A colon introduces information set up by the previous clause. Use it before a list, an example, or an explanation.
"There are three things I can't live without: coffee, good books, and long walks."
Semicolon (;)
A semicolon joins two related independent clauses together without a conjunction. Both sides need to be able to stand on their own as complete sentences.
"I ordered a coffee; it arrived cold."
Em Dash (—)
The em dash is the most versatile of the three. It can do a lot of jobs depending on context:
- Interject or abruptly change the subject
- Offset an appositive that contains commas
- Offset parenthetical information
- Replace a colon for emphasis
- Connect a list and another clause when the list comes first
- Communicate that a word or part of a word is missing or unknown
"She grabbed her coat—the one she wore on their first date—and walked out the door."