CIRCLE PITS / WALL OF DEATH

Moshing, also known early on as "slamdancing", is a style of dance whose participants push or slam into each other, usually while moving in circle. It is most associated with "aggressive" music genres, such as hardcore punk, rock and heavy metal. It is primarily done to live music, although it can be done to recorded music.
Variations of moshing exist, and can be done alone as well as in groups. Moshing usually happens in a "pit" (sometimes called a mosh pit or "circle pit") and is intended to be energetic not hurtful. Offshoots are "pogoing" (mostly jumping up and down) and the more extreme wall of death, and are typically done in an area in the center of the crowd, generally closer to the stage.
While moshing is seen as a form of positive feedback or expression of enjoyment, it has also drawn criticism over dangerous excesses occurring in offshoots. Injuries have been reported in mosh pits, and a few deaths have occurred in a "Wall of Death" an offshoot that developed when slamdancing was adopted at metal shows from its origin at punk shows. However, it is generally agreed that moshers are not trying to harm one another,and that they follow an unwritten "moshing etiquette".

Etymology
The term mosh came into use in the early 1980s American hardcore punk scene in Washington, D.C. Early on, the dance was frequently spelled mash in fanzines and record liner notes, but pronounced mosh, as in the 1982 song "Total Mash" by the D.C.-based hardcore band Scream. H.R. of the band Bad Brains, regarded as a band that "put moshing on the map,used the term mash in lyrics and in concert stage banter to both incite and to describe the aggressive and often violent dancing of the scene. To "mash it up" was to go wild with the frenzy of the music. Due to his Jamaican-accented pronunciation of the word, fans heard this as mosh instead. By the mid-1980s, the term was appearing in print with its current spelling. By the time thrash metal band Anthrax used the term in their song "Caught in a Mosh", the word was already a mainstay of hardcore and thrash scenes. Fans of Billy Milano and the band Stormtroopers of Death have often used the term mosh as an acronym for the phrase "move over shit head" during crowded shows. Through the mainstream success of bands like Anthrax, Nirvana, Stormtroopers of Death, and The Melvins, the term came into the popular vernacular.


 And I like this pict ! Lol so funny