Britain has long been regarded as a highly class-conscious society，with connotations of privilege and prejudice. Although divisions have recently become blurred，social class occupies an important position in British society and class identity remains strong. The way that people speak is obviously related to their social class background，and sociolinguistic research has determined that there are significant correlations between social class and language. Such studies can help us to better understand social structure and the development and maintenance of social relationships. This paper reviews a number of studies which have helped us to understand the nature of the varieties of English used by different strata of society in Britain. After a brief outline of the social class structure，the linguistic features of different social varieties are described. Some of the social and educational problems resulting from linguistic prejudice and dialect discrimination are then discussed.