Dialogue is a literary technique where two or more characters have a conversation. It is commonly used in fiction like novels, plays, and films. There are two main types of dialogue: inner dialogue where a character speaks to themselves revealing their personality, and outer dialogue which is a simple conversation between characters. An example of inner dialogue is from Wuthering Heights where a character urges someone to hurry, while an example of outer dialogue is a poem where two characters discuss the limitations of words.