Usage: "Wagwan, Steve"
It seems that every generation declares "hello" a fairly dull word in its infancy, subsequently putting much effort into working up a variety of alternatives to put a unique stamp on the rather tedious formality of greeting someone, from "all right?" to "yo" (now banished on pain of death in some inner-city boroughs). "Wagwan" is the latest bastardisation and can be used for a variety of situations, from a basic introduction through to "how are you?" with a slight change of intonation. Depending on what stories you believe, it is either a simple Jamaican patois condensing of "what's going on?" or evolved from African slaves being taught to speak English on Jamaican sugar plantations. A starting point for a history lesson, perhaps? Yoofspeak would be honoured.