Reposted from The Cripplegate.
There are three major kinds of irony: verbal, situational, and dramatic.
Verbal irony is when a person says something that they think is true, but while it turns out to not be true as they meant it, is still in fact literally true. For example, when Donald Trump—before becoming president—told President Obama that Obama would be “remembered as one of the worst Presidents” President Obama responded, “at least I’ll go down as a President.” While that statement turned out not to be true in the way President Obama meant it, it still was true in an even more ironic way. For an example more famous than American Presidents, in Star Wars Episode IV, Ben Kenobi tells Luke that Darth Vader killed Luke’s father. While that is not true in the way it sounded, it was nevertheless true in an entirely different and more profound way.
Situational irony is when the outcome of a narrative is the opposite of what was expected. For example, in To Kill a Mockingbird, the children spend the book fearful of Boo Radley, only to be rescued by him in the end. Situational irony is when the tables are turned in the grand finale. An example from real life: last year the fire station behind my house burned down. In terms of situational irony, that is about as extreme as it gets.