For those of you who might be asking, "Dab?" This is from Wikipedia:
The Dab is a dance in which the dancer simultaneously drops the head while raising an arm and the elbow in a gesture that has been noted to resemble sneezing… The Dab has its origins in the Atlanta hip-hop scene, but there is disagreement about who originated the dance.
There is also speculation that the dance originated from Dabbing, an action taken where someone snorts cocaine from their elbow while acting like they are sneezing.