Pavel Novotny

A pornographic actor/actress or a porn star is somebody who appears in pornographic films or photographs, live sex shows or peep shows. Most actors and actresses may appear nude in films (usually filmed in explicit sexual genres). Most genres have specialists who achieve most of their recognition in a specific niche market such as bondage, strap-on sex, gaping, general anal sex, double penetration or 'teenage' girls.

Some legal jurisdictions consider commercial pornography a form of prostitution, though most commercial sex film performers do not regard themselves as prostitutes for various reasons, but rather as artists. Most notably these performers are not paid directly by their sexual partners for the sex, but both are paid through a studio. Some sex film performers do not receive money at all for their inclusion in such films. In this instance, they do so for promotion of their other works, such as artistic paintings and sculptures, or they have no sex in some films, such as repeat performers in the famous Girls Gone Wild film series.

While the primary focus of heterosexual sex films are the women in them, who are mostly selected for their on-screen appearance, there is a definite focus on the male performers who are able to fulfill the desires of the male watching audience as their on-screen proxies. Most male performers in heterosexual pornography are generally selected less for their looks than for their sexual prowess, namely their ability to do three things: achieve an erection while on a busy film set, maintain that erection while performing on camera, and then ejaculate on cue.

Rocco Siffredi, Ron Jeremy, Peter North and John Holmes are probably the most famous male performers in porn films. Peter North is known for his ability to launch above-average amounts of semen at notable velocity from his penis on-screen which most other male performers can not do. Ron Jeremy is known for his large penis and an appearance very unusual for a porn star (he is overweight with large amounts of body hair). Adding to his fame, Ron Jeremy has been a staple in the industry since the '70s and has become something of a cultural icon.

While there is significant variation in anatomical proportions between people, there are many references to body proportions that are intended to be canonical, either in art, measurement, or medicine.

In measurement, body proportions are often used to relate two or more measurements based on the body. A cubit, for instance, is supposed to be six palms. While convenient, these ratios may not reflect the physiognomic variation of the individuals using them.

Similarly, in art, body proportions are the study of relation of human body, or in general, animal body, parts to each other and the whole. These ratios are used in veristic depictions of the figure, and also become part of an aesthetic canon within a culture.