Introduction

The article gives an introduction to the topics that are discussed in the book. Some of the topics that are covered in the book include phonological contrast and representation, prosodic organization, the structure and role of the lexicon, phonological and phonetic variation, sociophonetics, typological generalizations, speech perception and production, language acquisition, and historical change. The book examines different sources of speech, speakerrelated, message-related, and system-related variation, demonstrating the critical importance of engaging with such multifaceted and complex variation. It highlights the benefits of an integrated approach, rather than separating some aspects of variation as fundamental and other aspects as outside the domain of investigation. It also examines the content, access, and evolution of representations of speech, with special attention to the variety and richness of linguistic representations, relationships between levels of representation, and the challenges to current and future models of linguistic representations. It highlights the multidisciplinarity and diversity of methods that are the employed in the laboratory phonology.