Pornography or porn is the explicit portrayal of sexual subject matter. Pornography may use a variety of media, including books, magazines, postcards, photos, sculpture, drawing, painting, animation, sound recording, film, video, and video games. The term applies to the depiction of the act rather than the act itself, and so does not include live exhibitions like sex shows and striptease. A pornographic model poses for still photographs. A pornographic actor or porn star performs in pornographic films. If dramatic skills are not involved, a performer in porn films may be also be called a model.

A distinction is often made between erotica (the portrayal of sexuality with high-art aspirations, focusing also on feelings and emotions) and pornography (the depiction of acts in a sensational manner, with the entire focus on the physical act, so as to arouse quick intense reactions).

Pornography has often been subject to censorship and legal restraints to publication on grounds of obscenity. Such grounds and even the definition of pornography have differed in various historical, cultural, and national contexts. With the emergence of social attitudes more tolerant of sexuality and more specific legal definitions of obscenity, an industry for the production and consumption of pornography arose in the latter half of the 20th century. The introduction of home video and the Internet saw booms in a worldwide porn industry that generates billions of dollars annually.