In this lecture, I discuss the following topics about sociolinguistics:
*What do sociolinguists study?
*What determines language use?
*What is variety/code?
*What is the meaning of bilingualism?
*What is individual bilingualism?
*What is societal bilingualism?
*What is a first language?
*What is a second language?
*What is a foreign language?
*What is diglossia?
