Book excerpt: This book investigates linguistic variation as a complex continuum of language use from standard to nonstandard. In our view, these notions can only be established through mutual definition, and they cannot exist without the opposite pole. What is considered standard English changes according to the approach at hand, and the nonstandard changes accordingly. This book offers an interdisciplinary and multifaceted approach to this central theme of wide interest. The articles approach writing in nonstandard language through various disciplines and methodologies: sociolinguistics, pragmatics, historical linguistics, dialectology, corpus linguistics, and ideological and political points of view. The theories and methods from these fields are applied to material that ranges from nonliterary writing to canonized authors. Dialects, regional varieties and worldwide Englishes are also addressed.