[From a long-standing Wikipedia article worth reading]
What Is BDSM?
BDSM is a variety of erotic practices involving dominance and submission, role-playing, restraint, and other interpersonal dynamics. Given the wide range of practices, some of which may be engaged in by people who do not consider themselves as practicing BDSM, inclusion in the BDSM community and/or subculture is usually dependent on self-identification and shared experience. Interest in BDSM can range from one-time experimentation to a lifestyle, and there is debate[by whom?] over whether a BDSM or kink sexual identity also constitutes a form of sexual orientation.
The BDSM initialism
The term BDSM dates back to 1969;[1] however, the origin of the term BDSM is unclear and is believed to have been formed either from joining the term B&D (bondage and discipline) with S&M (sadomasochism or sadism and masochism), or as a compound initialism from B&D, D&S (dominance and submission), and S&M.[citation needed] Regardless of its origin, BDSM is used as a catch-all phrase to include a wide range of activities, forms of interpersonal relationships, and distinct subcultures. BDSM communities generally welcome anyone with a non-normative streak who identifies with the community; this may include cross-dressers, extreme body mod enthusiasts, animal players, latex or rubber aficionados, and others….