The novel is the most common form of fiction book. Novels are stories that typically feature a plot, setting, themes and characters. Stories and narrative are not restricted to any topic; a novel can be whimsical, serious or controversial. The novel has had a tremendous impact on entertainment and publishing markets.[27] A novella is a term sometimes used for fiction prose typically between 17,500 and 40,000 words, and a novelette between 7,500 and 17,500. A Short story may be any length up to 10,000 words, but these word lengths vary.