It's kind of a complicated question to answer because everyone involved in it has different preferences and likes different things but basically BDSM stands for Bondage, Dicipline, Sadism & Mashochism. It's kind of an umbrella term that includes people with all sorts of different fetishes and lifestyles. My husband and I have a Dominant / submissive relationship, meaning there is a power exchange in play. Basically I give away all he power in the bedroom to him. Should things go to far for me I of course have a safe word, but mostly it's about trust and pushing each other limits.