This book looks at native speaker varieties of English, considering how and why they differ in terms of their pronunciation, grammar, vocabulary and spelling. It shows how the major national varieties of English have developed, why similar causes have given rise to different effects in different parts of the world, and how the same problems of description arise in relation to all colonial Englishes. As an introductory text, it presupposes a minimum of previous knowledge, focusing on common traits rather than on individual varieties. It is informed by research on dialect mixing and includes exercises within each chapter and further reading references.