A maths teacher’s son fails maths! A swimming teacher’s son is terrified of water. These are examples of situational irony. Situational irony is when what happens is very different from what is expected or intended to happen.
When someone expresses very different feelings from what they mean or intend, we call it verbal irony. Verbal irony relies on how it is said (tone) as well as the actual words to convey the meaning. For example if you see a child looking very reluctant to go to school, and you say, “Wow, you must really love school,” that is verbal irony – you are actually saying that it is clear that the child does NOT love school.
A third form of irony is dramatic irony, which occurs when an audience or a reader are aware of something that the characters remain unaware of, for example, the audience knows that there is a shark under the water, but the swimmer in the movie is unaware of the problem. Dramatic irony creates tension – it can have you sitting on the edge of your seat, or biting your nails!
Sarcasm is a form of irony, but, while verbal irony is intended to be humorous, sarcasm is intended to hurt, insult or humiliate someone. Sarcasm is covered separately.