In the movie Kill Bill, a combination of real katanas and prop swords were used during filming. The specific swords used varied depending on the scenes, requirements, and safety considerations.

For certain close-up shots and non-action scenes, real katanas or high-quality replicas that closely resembled authentic katanas may have been used. These swords would typically have a blunted or dulled edge to ensure the safety of the actors and the film crew during filming.

However, during action sequences and fight scenes, it is common for prop swords to be utilized. Prop swords are specially designed for film production and are made from materials such as rubber, foam, or other lightweight materials that are safer for actors and stunt performers.

The choice between real katanas and prop swords depends on factors such as the level of realism required, the choreography of the fight scenes, and the safety protocols in place during filming.

It's important to note that when it comes to action scenes and stunts, the swords used in movies are carefully managed and supervised by professional sword handlers and stunt coordinators to ensure the safety of the cast and crew.