Western world's change of attitude towards sexuality.
Throughout the history of erotic depictions , various groups within society have considered them to be noxious, and made attempts to have them suppressed under obscenity laws, censored , or made illegal. Such grounds and even the definition of pornography have differed in various historical, cultural, and national contexts. Starting from the mid-twentieth century, societal attitudes towards sexuality have become more lenient in the Western world , and legal definitions of obscenity made limited.