Wu-tang is a dance originating in Philadelphia before spreading throughout the surrounding region.
Each individual person adds their own spin to the dance, be it fancy footwork or the mimicking of gunshots.
A similar Philly dance is the "D-Mack" or "D-Mac," in which a dancer moves his arms or legs on one side of his body (often in a similar motion as the Wu-tang), and then imitates the same moves on the other side of his body.
The dance bears no apparent or evident relation to the hip hop group "Wu-Tang Clan" nor does it to the style of martial arts known as Wutang, though the name of the dance itself may have been derived from either source.
Ciara can be seen doing part of the dance in her music videos for songs "Work" and "Gimmie That Bass".