The resulting consent and understanding is occasionally summarized in a written "contract", which is an agreement of what can and cannot take place.
Some have a policy of panties/nipple sticker for women (underwear for men) and some allow full nudity with explicit sexual interaction allowed.The fundamental principles for the exercise of BDSM require that it should be performed with the informed consent of all involved parties.For the medical condition in which pain/humiliation is required for sexual arousal and causes distress or impairment, see Sexual masochism disorder.BDSM is a variety of often erotic practices or roleplaying involving bondage, discipline, dominance and submission, sadomasochism, and other related interpersonal dynamics.Since the 1980s, many practitioners and organizations have adopted the motto (originally from the statement of purpose of GMSMA—a gay SM activist organization) "safe, sane and consensual", commonly abbreviated as "SSC", which means that everything is based on safe activities, that all participants be of sufficiently sound/sane mind to consent, and that all participants do consent.
Some BDSM practitioners prefer a code of behavior that differs from "SSC" and is described as "risk-aware consensual kink" (RACK), indicating a preference for a style in which the individual responsibility of the involved parties is emphasized more strongly, with each participant being responsible for his or her own well-being.
BDSM is now used as a catch-all phrase covering 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, body modification enthusiasts, animal roleplayers, rubber fetishists, and others.
The terms "top" and "bottom" are also used: the top is the instigator of an action while the bottom is the receiver of the action.
The two sets of terms are subtly different: for example, someone may choose to act as bottom to another person, for example, by being whipped, purely recreationally, without any implication of being psychologically dominated by them, or a submissive may be ordered to massage their dominant partner.
Despite the bottom performing the action and the top receiving they have not necessarily switched roles.