Irony is the word used to indicate the gap between appearance and reality. When we think of irony, there are three main types that we can enounter. The first is verbal irony, which is when we say the opposite of what we mean. Take, for example, the following scenario. You have just done a presentation for me as your teacher in class, and it was terrible. I, as a cruel teacher, say to you, "Well that was wonderful." That is the opposite of what was true, and thus it is an example of verbal irony.
Situational irony is a twist of fate that results in an ending that is completely the opposite of what we expect. An excellent example of this occurs in "The Gift of the Magi" by O. Henry, when both Della and Jim sell their most precious possession in order to buy a gift that can now no longer be used by their partner.
Lastly, dramatic irony is when we as the audience or one or more characters knows something that other characters do not or are blind to. Perhaps one of the most famous examples is in Romeo and Juliet, when we as the audience know at the end of the play that Juliet is not dead and that she is just about to revive. However, Romeo does not, and he kills himself just before she wakes up.
irony is when we say something and intended another meaning
when the words say something and mean another