Since the 1990s, this genre has also received attention in academic circles, where it is sometimes called paracinema. Their producers used sensational elements to attract audiences lost to television. The Motion Picture Association of America (and the Motion Picture Producers and Distributors of America before it) cooperated with censorship boards and grassroots organizations in the hope of preserving the image of a 'clean' Hollywood, but the distributors of exploitation film operated outside of this circuit and often welcomed controversy as a form of free promotion. Such films were first seen in their modern form in the early 1920s, but they were popularized in the 60s and 70s with the general relaxing of censorship and cinematic taboos in the U.S. Exploitation films may feature suggestive or explicit sex, sensational violence, drug use, nudity, gore, the bizarre, destruction, rebellion, and/or mayhem.
