Here’s what BDSM actually stands for:

BDSM includes bondage and discipline (B&D), Dominance and submission (D&S), and sadism & masochism (S&M). The terms are put in together that way because BDSM can be a lot of different things to different people with different preferences. Most of the time, a person's interests fall into one or two of those categories, rather than all of them.