Dips are common to many partner dance styles (Tango, Lindy Hop, Salsa, Ballroom dances), as well as couple's Disco.[1]
Characteristics of a dip include:
Some dance styles distinguish between sits, dips, and drops; as a general rule, the difference is the degree to which the base (usually the leader) ends up responsible for the mass and balance of the flyer (usually the follower). Where a distinction is made, it's usually a continuum from least to most responsibility, with sits being the least, drops the most, and dips in between.
Difficulty of the dip moves varies, with some dips being easy, and some requiring "considerable strength and flexibility".[1]