Irony, my favorite!
Verbal Irony: Using words to make them seem something different than what they appear to mean. Example: A very dirty room is awarded a cleanliness award.
Dramatic Irony: When the audience is more aware of what is going on more than the actual characters. Example: In a scary movie someone plans to go into a house where a monster is but the audience already knows the monster is there.
Situational Irony: When something expected to happen is different than what actually happens. Example: An airplane pilot is scared of heights.