An auteur is a filmmaker who exerts strong authorial control and influence over their movies, resulting in a distinct style that is recognizable across their body of work. The document discusses Quentin Tarantino as an auteur, analyzing three of his films - Reservoir Dogs, Inglourious Basterds, and City on Fire - to identify recurring styles in his filmmaking such as explicit violence, engaging dialogue, contrasting music sequences, distinctive soundtracks, and recurring collaboration with certain actors and actresses.