Gross-out is a subgenre of comedy movies in which the makers employ humor that is willfully "tasteless" or even downright disgusting. It usually involves gratuitous nudity, unrealistic aggressiveness towards property or Schadenfreude. The movies are generally aimed at a younger audience aged between 18 and 24. One boon of this genre is that it provides an inexpensive way to make a movie "edgy" and to generate media attention for it.
In the United States, following the abolition of the film industry's censorious Production Code and its replacement with the MPAA film rating system in the late 1960s, some filmmakers began to experiment with subversive film comedies, which explicitly dealt with taboo subjects such as sex and other bodily functions. Noteworthy examples include 1972's Pink Flamingos (in which the central character eats dog excrement) and other films by John Waters, and 1974's sketch comedy film The Groove Tube. As these films emerged from the counterculture movement and gained a measure of audience success, they inspired more mainstream films to follow their example. However, long before the Production Code, early silent comedy film makers produced and attempted several 'gross-out' pictures to the disdain of early film reviewers. One such example is the lost Nell's Eugenic Wedding starring Fay Tincher and Tod Browning.
The label "gross-out movie" was first applied by the mainstream media to 1978's National Lampoon's Animal House, a comedy about the fraternity experience at US colleges. Its humor included explicit use of bodily functions (like projectile vomiting). It was a great box office success despite its limited production costs and thus started an industry trend. Since then, gross-out films increased in number, and became almost the norm for American comedy films. Some films of this genre could be aimed at teen audiences (such as Superbad, Porky's, American Pie or Eurotrip), while others are targeted at somewhat more mature audiences (such as Borat, The Hangover or Wedding Crashers).
Beavis and Butt-Head, The Ren & Stimpy Show, and Aaahh!!! Real Monsters, all appearing in the early 90s, pioneered gross-out humor on television. The Tom Green Show and Jackass and its UK cousin, Dirty Sanchez brought this sensibility to live action. The shows featured dangerous stunts, nudity, and profanity. Both series were featured on MTV, and progressed to feature-length movies. Today this continues with shows on Adult Swim, such as Tim and Eric Awesome Show, Great Job!, Check It Out! with Dr. Steve Brule, The Eric Andre Show, and animated shows like South Park, Family Guy, The Simpsons (primarily in the Itchy & Scratchy Show parodies of violent cartoon animal cartoons, and in the Halloween episodes), Rick and Morty, Invader Zim, and Big Mouth.
The prime examples of the above are the stage version of the contemporary drama Trainspotting by bestselling playwright and author Irvine Welsh; the controversial New York musical Urinetown by Kotis and Hollmann; the outrageous anarchistic schlockomedy (shock horror comedy) musical about a Manchester jobcentre Restart by Komedy Kollective; and performances by another United Kingdom-based act, Forced Entertainment, who devised the iconic theatrical gorefest Bloody Mess.
Various artists helped create a flourishing gross-out art scene, which began mainly in the 1990s, the most famous of which were Damien Hirst, known for encasing mutilated, rotting cattle in formaldehyde, and making art of endangered marine species such as sharks in formaldehyde tanks, and Tracey Emin, whose exhibit of an unmade bed featured used tampons, condoms and blood-stained underwear.
Gross out themes are common in popular music genres, such as hip hop and hard rock, where shock value helps create marketable notoriety. Bands include Blink-182 famous for including breast and fart jokes in their songs, while bands such as Cannibal Corpse and Agoraphobic Nosebleed write extremely revolting lyrics designed to induce nausea and shock the music world.
Probably the biggest gross-out shock to the music world was the act of GG Allin. Allin was infamous for his transgressive music act, which included eating excrement, mutilating himself and attacking audience members.
Sometimes the line between truth and urban myth is blurred by the sensationalist sections of the media. For example, Frank Zappa never ate steaming excrement live on-stage, and the famed incident involving Ozzy Osbourne biting a head off of a bat was actually unintentional (he thought the bat was a prop).