A Disneyland cast member is a Disneyland employee. This term includes every employee from the security person checking bags as you enter to the dancer in the nighttime spectacular. Each cast member has an important role.
If you have a positive interaction with a Disneyland cast member, in addition to thanking that person in the moment, you can take note of your location and the name and other information (like hometown or favorite character) on the cast member’s oval name tag pin. With any of this information, you can submit a “cast compliment” through the Disneyland app.