Out of all punctuation, I feel that semicolons are the most misused. A lot of people seem to look at them and go, “What the hell is that? Eh, just throw it in there.” Or, when they should use a semicolon, they instead use a comma or a dash.
Good news: semicolons are super easy to use.
They might look weird, but they’re super useful. Semicolons divide two closely related, complete sentences.
Let’s look at an example:
Dean’s mother had been killed by demons; there was nothing more satisfying than sending one back to Hell.
If you replaced the semicolon with a period, you would have two sentences that could stand on their own while being grammatically correct.
What about this sentence?
Now, it was just him and Sam left; and the Impala, too.
Here, the semicolon is not properly used, because while the section to the left is a complete sentence, “and the Impala, too” is not.
The only other thing to keep in mind about semicolons is that the sentences they connect are usually very closely related and is used to emphasize that relationship.