Top, bottom, switch

The terms top, bottom, and switch are used to describe an individual's role during a sexual act.

They may more broadly denote a psychological, social, or sexual identity, or indicate one's usual preference.

Older terms of "active", "passive", and "versatile" are still often used, especially in the context of gay sex.

In both types of relationships - top/bottom and dominant/submissive - consent, negotiations, and mutual respect and support for one another are keys to healthy dynamics.

Beginning in the 1970s, in some American contexts, people would identify their interests by wearing a set of keys on the side of their belt or a color-coded handkerchief in their rear pockets.

BDSM couples, with the femme tops sitting on male bottoms who are kneeling, leashed and in handcuffs, at 2006 Cologne Pride , Germany.
A nude submissive in "Inspection" pose - used in some forms of D/s dynamics.
A gagged woman with bound hands sits in a submissive position. Her partner holds her with a chain leash tied around her neck at Folsom Street Fair .