 A viewing of films featuring the work of Dean Collins in the 1940s, and rock 'n' roll films made in the mid-1950s reveals the fact that dancers turn frequently and inevitably turn their backs to the camera.Although another unslotted swing dance, Balboa, became popular in the same area and under the same conditions, much has been made of "jitterbugging in the aisles" as a source of the slotted style.Slotted moves were a common part of the step vocabulary of Lindy and jitterbug dancers during the 1940s and 1950s.