Violent television programming is a proven product that guarantees an audience, and it is easy to write and inexpensive to produce. Children are exposed to violence on programs that range from cartoons to the new breed of "reality" shows, such as actual police operations. Censorship and limits have always been an accepted part of television, especially on broadcast TV. Even the most violent shows still cannot use some of the words commonly used on the street that are considered offensive; neither can they show nudity. Violence, however, has been permitted. The movement to curb violent TV is less an attempt to curtail television's first amendment rights than to limit the access of younger viewers to harmful programming. The American Medical Association supports equipping new television sets with a microprocessor that would allow households to screen out violent programs and has called on advertisers to pull their ads from violent shows. The American Medical Association, along with other organizations, also advocates guidelines and a violence rating system for programming during prime time and children's viewing hours. The standards would be enforced through fines and a threat of license revocation.