A gang bang is a situation in which several people, usually more than three, engage in physical sexual activity with one specific person sequentially or at the same time.^[1] That specific person is the central focus of the sexual activity;^[1] for example, it could be one woman surrounded by several men, or a man with multiple women (a "reverse" gang bang). Rather than serial couplings by two people, the gang bang is defined by the number and simultaneity of the various sex acts, such as vaginal, anal or oral sex, or double or triple penetration.

The largest gang bangs are sponsored by pornographic film companies, and recorded, but a gang bang is not unusual in the swinger community. It is more often considered to have multiple men and one woman, while a so-called "reverse gang bang" (one man and many women),^[2] which can be seen in pornography. Male-on-male gang bangs also happen.^[3]

Gang bangs are not defined by the precise number of participants, but usually involve more than three people and may involve a dozen or more. When the gang bang is organized specifically to culminate with the (near) simultaneous or rapid serial ejaculations of all male participants on the central man or woman, then it may be referred to by the Japanese term bukkake.^[1]

By contrast, three people engaged in sex is normally referred to as a threesome, and four people are normally referred to as a foursome. Gang bangs also differ from group sex, such as threesomes and foursomes, in that most (if not all) sexual acts during a gang bang are centered on or performed with just the central person. Although the participants of a gang bang may know each other, the spontaneity and anonymity of participants is often part of the attraction. Additionally, the other participants normally do not engage in sex acts with each other, but may stand nearby and masturbate while waiting for an opportunity to engage in sexual activity.

Though there have been numerous gang bang pornographic films since the 1980s, they usually involved no more than half a dozen to a dozen men. However, starting with The World's Biggest Gangbang (1995) starring Annabel Chong, the pornographic industry began producing a series of films ostensibly setting gangbang records for most consecutive sex acts by one person in a short period.^[4]

These kinds of films were financially successful, winning AVN Awards for the best selling pornographic films of their year; however, the events were effectively unofficiated and the record-breaking claims often misleading.^[5] Jasmin St. Claire described her "record", purportedly set with 300 men in World's Biggest Gang Bang 2, as "among the biggest cons ever pulled off in the porn business", with merely about 30 men "strategically placed and filmed," only ten of whom were actually able to perform sexually on camera.^[6]