Renye adds that people often have more than one kink or one fetish, and there is often overlap: For instance, someone may engage in spanking as part of a role-playing scenario in which one partner is dressed up as a schoolgirl and the other like a professor. BDSM is kinky, but not all kinks fall under the BDSM umbrella. When we think of kink, we often think of BDSM, which involves an erotic power exchange through dominance and submission. (There's also the category of turn-ons: things that simply arouse a person.) If someone has a bondage fetish, their entire sexuality may revolve around restraint.
Think of the differences this way: If someone's kink is bondage, they probably get incredibly excited when they're tied up. While people often use the terms 'fetish' and 'kink' interchangeably, a kink means an activity or behavior that someone enjoys that exists outside the 'norm' of 'traditional' sex, such as incorporating handcuffs or even balloons.