Modern Aesthetic History
As amelinda notes, BDSM is a largely marginalized set of sexual practices, and as such it is a difficult thing to trace historically. The commonly accepted theory within the community is that BDSM emerged from World War II soliders, who sexualized the intense emotions of their wartime experiences and associated them with the severe utilitarian aesthetics and the psychological domination required of the military. Upon returning back home to the States, soliders found a similar aesthetic in the motorcycle community, specifically the Harley-Davidson community. BDSM’s aesthetics (specifically its love of leather, buckles, metal studs, and machismo) thereby emerged as a hybrid of mid-century motorcycle and military look-and-feel.

The evolution of the practices of BDSM is much harder to trace. It can be said with certainty, though, that the emergence of the Internet linked practicioners worldwide, who found mutual support, access to global storefronts for equipment, shared practice, and even a desire to formalize the history and culture around BDSM.

Modern practice (an overview)
BDSM is practiced differently by every person who participates. There are, however, certain recognized commonalities.

  • The DOM, or dominant, assumes control and responsibility of the scene. A Master is someone who exclusively assumes this Dominant role. One typographic convention in the community is that the name of the DOM, or Master, is entirely capitalized, to dinstinguish this person from the sub.
  • The sub, or submissive, grants the DOM control and responsibility. A slave is someone who exclusively assumes the submissive role. One typographic convention in the community is that the name of the sub, or slave, is entirely written in lower case, to distinguish this person from the DOM.
  • In the negotiation, which occurs before and outside of the scene, the sub and the DOM discuss what they expect from the scene and their personal boundaries.
    Sometimes the DOM and the sub will discuss specific desires for the beginning, middle, and end of the scene. The safeword is often defined in the negotiation.
  • The scene is when the BDSM takes place, where the negotiation plays out. This is what most people think of when they hear the term BDSM.
  • The safeword is the safety catch for the scene. If either participant feels that the scene is getting out of hand or too much for him/her to handle, by speaking the safeword, he/she signals to the other that they wish the scene and its fantasy to stop immediately. It signals that they want to take back control and responsibility for themselves. Notably, any verbal communication other than the safeword can be considered part of the scene.

Sources: My leather daddy uncles, willingly sharing with their wee vanilla nephew