What is irony?

Irony is a verbal or situational context involving outcomes that are either unexpected, unanticipated, or actually the opposite of what they should be. A statement may be intended to mean the opposite what it normally means, or an event can occur that is unexpected. Sometimes it can be so unexpected that it's funny. For example: a man steps around a mud puddle to avoid getting his shoes wet, but steps on a broken sprinkler line which sprays him head to toe. Another example would be a thief who steals a car, only to be caught because the car belongs to the police commissioner.
The 3 different types of irony are:

• verbal - similar to sarcasm, but not necessarily insulting.
  For example, an overachiever who passed a test says, "I bombed the test."
• situational - when a surprising and unexpected event occurs.
  For example, a professional swimmer almost drowns.
• dramatic - when the character of a story doesn't know something but the reader/viewer does, and acts in a way that is obviously ill-advised.
  For example, in a Horror movie, a person wanders into an abandoned house. We can predict that ghosts will start playing tricks on that person, but he/she seems unaware of the ghosts.

The use of Words to express the opposite of their literal meaning.