Two well-known examples of irony in literature are found in "Oedipus Rex" and "The Rime of the Ancient Mariner." In the first example, Oedipus unknowingly brings a curse upon himself by his own orders. In the second, the mariner is dehydrated in the midst of water.
Dramatic irony is a type of literary device that occurs when the audience knows about a particular situation that one or more of the characters do not understand.
In the drama "Oedipus Rex" by Sophocles, a plague has come upon the land, and Oedipus learns that the murder of Laius has caused it. He vows to end the plague by bringing about justice and the condemnation of the murderer. The audience already knows, though Oedipus does not, that Oedipus himself killed Laertes and later married his own mother. By cursing the murderer, he is cursing himself.
Situational irony is abundant in the poem "Rime of the Ancient Mariner" by Samuel Taylor Coleridge. Situational irony occurs when things are different from what is expected. In the poem, the ancient mariner and his crew are in the midst of the ocean. The mariner kills an albatross that the crew believes to be a sign of misfortune. The men are all soon hot, miserable and dehydrated. Their throats are so dry and parched that they cannot speak, and their lips are baked from the sun. Yet when they look out, they see "water, every where." The situational irony of needing water so badly, even in the midst of it, and yet not being able to drink it only adds to the misery of their predicament.