The term Greebo originates from 1950s bikers who had greased back hair hence "greebo". Many people use the word "Greebo" in reference to teenagers who listen to rock bands and dress in a manner which distances themselves from the masses. Chavs/trendies/townies etc have been fighting with greebos since the legendary "mods and rockers". Today, we see two subcultures opposing each other, Chavs and Greebos. While chavs have a tendency to be on the less academic side, a large portion of greebos continue on through further education. This is mainly due to the class divide. It has been noted by numerous sociological sources that Chavs are predominantly working class; while "Greebos" are predominantly middle class.
Chavs should be nice to greebos because one day they'll be working for one!