British Creole is spoken by British born people of Caribbean background whose parents, grandparents or great grandparents have migrated to Britain since 1948. It is an ethnic variety, rather than a regional or local one. British Creole is the product of dialect contact between West Indian migrants, the largest group of whom were Jamaican during the period of critical formation (1950-1970), and vernacular varieties of urban English English. Because of the Jamaican input, most apparent at the lexical and grammatical level, British Creole has been described as a collection of local British varieties of Jamaican Creole. Speakers of British Creole (who usually call the language Patois or Patwa), from the second generation onwards, are all bilinguals or multilinguals. At a very early age, they acquire a local variety of British English; at school if not earlier, they will be exposed to Standard English as well. In the second and later generations, code switching in private conversations is common, with local English English predominating over Creole. Although grammatical, phonological and lexical evidence indicates clearly that British Creole is based on Jamaican Creole, its speakers are not confined to the descendents of Jamaicans.