‘Irony takes many forms.
In irony of situation, the result of an action is the reverse of what the actor expected. Macbeth murders his king hoping that in becoming king he will achieve great happiness. Actually, Macbeth never knows another moment of peace, and finally is beheaded for his murderous act.
In dramatic irony, the audience knows something that the characters in the drama do not. For example, the identity of the murderer in a crime thriller may be known to the audience long before the mystery is solved.
In verbal irony, the contrast is between the literal meaning of what is said and what is meant. A character may refer to a plan as brilliant, while actually meaning that (s)he thinks the plan is foolish. Sarcasm is a form of verbal irony.’