They may seem tricky, but they're easy to master.
You’ve probably seen these two little dots, one on top of the other, scattered throughout your reading material. But do you really know what they’re used for? The colon is not something that shows up in the majority of sentences, like a period or a comma. And its use is not outwardly obvious like an exclamation point or a question mark. So here’s a crash course in exactly when to use a colon. It’s good for a whole lot more than making the “eyes” of a smiley face emoticon, that’s for sure!
What is a colon?
A colon is an introductory punctuation mark. Its primary use is to present the information following the colon as something that builds upon the information before it. That sounds confusing, but it’s not as complicated as you think!
When to use a colon: Introducing a list or example
This is probably the best-known way to use a colon. You can use it to introduce a list or series, as in, “I’m excited for my classes this semester: Biology, History, English and Algebra.” Here’s another example: “Please get these things when you go to the store: cheese, oranges, bread and crackers.”
The items in the list can also be sentences on their own; they don’t have to be comprised in a single sentence. For instance, “Here are my conclusions: One, English grammar is complicated. Two, I want to get better at it. Three, I should read more grammar articles on Reader’s Digest.”
But the thing that you’re introducing with a colon doesn’t have to be a list. As you may have noticed, I used a colon in the first paragraph of this section, to introduce an example for when to use a colon! You can follow phrases like “Here’s an example” or “Try this” with a colon.