Grammar girl here, sometimes people ask me about the difference between a colon and

a dash since they can both be used to introduce the next part of a sentence.

So today we're going to talk about how a dash is different from a colon and also when

you can use a comma in their place.

Although they also have other uses, dashes and colons can both be used to introduce the

next part of a sentence and the difference between the two marks is subtle.

A dash is a stronger and more informal mark than a colon.

Take of a colon as part of the sentence that just ambles along.

Squiggly has two hobbies and now I'm going to tell you what they are, colon, playing

jokes on ardvark and cooking.

A colon informs the reader that something more is coming along.

The words after the colon define or clarify what came before the colon.

The two unknown hobbies before the colon are defined after the colon as playing jokes

on ardvark and cooking.

A dash can also introduce extra or defining material, but well, a dash is quite a dramatic

punctuation mark.

A dashing young man is certainly not an ordinary young man and if you're dashing off to the

store, you're not just going to the store, you're going in a flurry.

A dash interrupts the flow of the sentence and tells the reader to get ready for some

important or dramatic statement.

If you used a dash in our hobbies sentence, it would conceptually read something like

this.

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