Twerking is a type of dance that emerged out of the bounce music scene of New Orleans in 1990, which has a broader origin among other types of booty dancing found among the African diaspora that derives from Bantu-speaking Africans of Central Africa. It is a sexually provocative dance that involves performers, mostly women, dancing to popular music in a sexually suggestive manner involving throwing or thrusting their hips back or shaking their buttocks, often in a low squatting stance. Twerking is part of a larger set of characteristic moves unique to the New Orleans style of hip-hop known as "bounce". Some of the moves include "mixing", "exercising", the "bend over", the "shoulder hustle", "clapping", "booty clapping", "booty poppin", "the sleeper" and "the wild wood".
According to the Oxford English Dictionary, twerking is defined as dancing "in a sexually provocative manner, using thrusting movements of the bottom and hips while in a low, squatting stance". Merriam-Webster gives the definition as a "sexually suggestive dancing characterized by rapid, repeated hip thrusts and shaking of the buttocks especially while squatting".
There are several tutorials available on YouTube and wikiHow that teach how to twerk, including basic moves and variations.
