Swinging, or Swingers, where partners are exchanged for casual sexual gratifications, most notably wife swapping.
The non meaningful exchange of partners with others, with the express purpose of having some form of sexual relations, either separately from the others, though usually within view of the other partner.
[Soft Swap - Soft Swinging] refers to the act of kissing and oral sex with three or four others persons, but not engaging in intercourse.
[Full Swap] means going all the way. Where full intercourse occurs among partners, but not with the 'spouse'. Generally one will be watching, though it is not unusual for the other to be equally engaged with another partner.
[Group Sex] Where sex is among several different people, all located in the general vicinity. Switching of partners is normal in such settings, and can refer to one on one, threesomes, or more depending on the number attending.
Ancient] Swinging is generally considered to have derived from early depiction of Roman Orgies. The casual acceptance of multiple sex parties in an open atmosphere is claimed to be the guiding force behind some modern day swingers.
History (Legend): Modern day purists claim that swinging came into vogue among US Air Force Pilots and their wives during WWII. There is no actual factual details, though legend is that as the attrition rate among pilots was high during the war, that wives were shared, so as to create a bond among the men, thus those who survived would protect and look after the widow.
However, wives generally didn't accompany their men to foreign posts, so the legend is a bit thin on reality.
There are clubs or organizations that practice the art of swinging, though in Gay Culture it is not a widely used term. However things such as 'white parties' can be considered as part of swinging.
The primary requisite to be a swinger isn't about random sex with several partners. It is about having a significant other, where both partners engage in sex with multiple partners, in agreement.
Practice (Associated Acts): In the more 'bondage' scenario, where a 'master' will allow his 'slave' to be made available for other 'masters' or such. In some instances, this is done as a test, or also as a form of 'training'.
'Swinging' is more of a heterosexual act, though in the Domination / Submission culture of gay sex, the swapping of 'slaves' is considered to be part of the 'swinging' culture. In addition, 'dogging' is also considered to be classed under the 'swinger' description.
Noteworthy: Mary Carey is a noted public supporter of the lifestyle.
To define a commitment of two people, that revolves around a deeper relationship, where sex is not considered an exclusive requirement for being committed. 'Open Marriage' is the general definition. Though it does not necessarily mean that both are witnesses to the sexual trysts of the other.