1968年以前,美国电影协会未制定分级制度,后来在导演和制作单位呼吁更大的艺术创作自由的压力下,电影分级制度于1968年11月1日出台。*G级:大众级,所有年龄均可观看。影片没有裸体、性爱场面,吸毒和暴力场面非常少。对话也是日常生活中可以经常接触到的;*PG级:普通辅导级,建议在父母的陪伴下观看。该级别的电影基本没有性爱、吸毒和裸体场面,即使有时间也很短,此外,恐怖和暴力场面不会超出适度的范围; Before 1968, the American Film Institute did not develop a hierarchical system, and later the film grading system was introduced on November 1, 1968, under pressure from directors and production units for greater freedom of artistic creation. * G-class: general level, all ages can be watched. The film has no nudity, sex scenes, very few scenes of drug abuse and violence. Dialogue is also often accessible in daily life; * PG level: general counseling level, it is recommended to watch in the company of their parents. This level of film is basically free of sex, drug abuse and nudity, even if time is short, and in addition, the scene of terror and violence will not go beyond the proper range;