Gumperz was, for most of his career, a professor at the University of California in Berkeley. His research on the languages of India, on code-switching in Norway, and on conversational interaction, has benefitted the study of sociolinguistics, discourse analysis, linguistic anthropology, and urban anthropology. John Gumperz developed a new way of looking at sociolinguistics with Dell Hymes, also a scholar of sociolinguistics. Their contribution was a new method called the "ethnography of communication." Gumperz' own approach has been called Interactional sociolinguistics. Sociolinguistics analyzes variation in discourse, within a particular speech community, and studies how that variation affects the unfolding of meaning in interaction and correlates with the social order of the community. Gumperz built on Hymes's work by looking at differential power between speech communities. In particular, Gumperz noted that the "standard" form of any given language (i.e., the form that is expected in formal situations, the form that one hears on the news) is the dialect of those who are already powerful. He called this the "prestige dialect," and noted that those who did not speak that dialect natively, but rather had a stigmatized or less powerful native dialect, were "diglossic" (fluent in their native dialects and able to use the prestige dialect, too), whereas those whose native dialect was the prestige dialect were rarely able to use other codes Gumperz defines the speech community as "any human aggregate characterized by regular and frequent interaction by means of a shared body of verbal signs and set off from similar aggregates by significant differences in language usage."