A commentary track is a feature on a DVD or Blu-ray disc that allows viewers to listen to audio commentaries by filmmakers, actors, and other individuals involved in the production of a movie while watching the film. These commentaries provide insightful information about various aspects of the filmmaking process, including the storyline, characters, cinematography, special effects, music, and more. The commentators often share their thoughts, memories, and experiences related to specific scenes or moments in the movie, providing a deeper understanding and appreciation for the artistry involved in making a film.