The dispenser, which was located out of reach in the McFly kitchen, could only be used by speech recognition, and was programmed to respond only to authorized persons, and only then if the voice command was made correctly. Martin McFly, Jr. was unable to get a snack from the dispenser merely by saying "Fruit!" or "Hey, fruit!", and had to add the universal 'magic word' to his request. When he said "Fruit, please!" no matter how insincerely, the unit would lower from the ceiling of the kitchen. Marty Jr. then had to add "Thank you!" in order for the dispenser to open (or at least for it not to retract). Evidently, the programming was done in an effort to try to teach 17-year-old Marty Jr. how to be polite; his sister, Marlene, was able to use the dispenser without any special protocol.