Slapping palms as a form of greeting a friend and then holding their hand as you pull your fingers back until it makes a snapping sound.

digital authentication protocol

a greeting mechanism that can consist of or combine multiple methods of hand based interaction (e.g. handshake/fistbump)

The knocking of fists together as a greeting, or form of respect

The knocking of fists together as a greeting, or form of respect.

If one person's ass is penetrated by two objects, it is generically called double anal penetration (sometimes abbreviated dp).

Double-Double: Multiple penetration by four penises. Two penises in the mouth and anus simultaneously.

Triple-Double: Multiple penetration by six penises. Two penises in the mouth, vagina, and anus simultaneously.

To knock fist together as a form of greeting, usually used on the Eastside

The touching, or smashing, of two fists (of different persons) together as a sign of greeting, camaraderie or achievement.