Book excerpt: Sociolinguistics is the study of the interaction between language and society. In this classic introductory work, Janet Holmes examines the role of language in a variety of social contexts, considering both how language works and how it can be used to signal and interpret various aspects of social identity. Written with Holmes' customary enthusiasm, the book is divided into three sections which explain basic sociolinguistic concepts in the light of classic approaches as well as introducing more recent research. This fourth edition has been revised and updated throughout using key concepts and examples to guide the reader through this fascinating area, including: - New sections on: koines and koineisation linguistic landscapes New Englishes Stylisation language and sexuality societal approaches to attitude research forensic linguistics - A new selection of informative examples, exercises and maps -Fully updated further reading and references sections An Introduction to Sociolinguistics is an essential introductory text for all students of sociolinguistics and a splendid point of reference for students of applied linguistics. It is also an accessible guide for those who are simply interested in language and the many and varied uses we put it to.