What role did the Hays Code play in the censorship of American movies during the twentieth century?

The Hays Code, officially known as the Motion Picture Production Code, was a set of self-imposed guidelines by Hollywood studios that regulated the moral content of films from 1934 to 1968. Established to preempt government censorship, it forbade profanity, obscenity, and graphic depictions of violence, criminality, substance use, promiscuity, miscegenation, and homosexuality. The code aimed to prevent lowering moral standards and ensure that wrongdoing was always condemned. It significantly influenced storytelling, particularly in genres like romantic comedies, where explicit sexual relationships were prohibited, leading to increased reliance on verbal wit and physical humor. The Hays Code was eventually replaced by a voluntary rating system in 1966 and later by the Classification and Ratings Administration in 1968.123