Irony (from the Ancient Greek εἰρωνεία eirōneía, meaning hypocrisy, deception, or feigned ignorance) is a literary or rhetorical device, in which there is an incongruity or discordance between what one says or does and what one means or what is generally understood. Irony is a mode of expression that calls attention to the character's knowledge and that of the audience.
There is argument about what qualifies as ironic, but all senses of irony revolve around the perceived notion of an incongruity between what is expressed and what is intended, or between an understanding or expectation of a reality and what actually happens: the literal truth is in direct discordance to the perceived truth.