During his visit to Leningrad, Burgess encountered the stilyagi, gangs of thuggish Russian teenagers. While Burgess was eating dinner at a restaurant one night, a group of bizarrely dressed teenagers pounded on the door. Burgess thought they were targeting him as a westerner, but the boys stepped aside graciously when he left and then resumed pounding. Burgess insists that he based nadsat—the invented slang of his teenage hooligans in A Clockwork Orange—on Russian for purely aesthetic reasons, but it seems likely that this startling experience influenced his portrayal of Alex and his gang. Along with English Teddy Boys, a youth culture of the 1950s and 1960s associated with American rock music, the Russian gangs provided a template for the hoodlums in AClockwork Orange.