Mode in literature is the way that a writer chooses to tell a story. For example, they might choose to tell the story in first person (where the story is told by a character in the book, using "I") or third person (where the story is told by someone outside the story, using "he" or "she"). Mode can also include things like the mood of the story, the types of stories being told, and the way different characters are portrayed in the plot.