The term identity is used ubiquitously, but rarely explained. What exactly is identity? Identity: A Very Short Introduction provides a survey of the many faces of the concept of identity, and discusses its significance and varied meanings in the fields of philosophy, sociology, psychology, linguistics, as well as politics and law. Tracing our concern with identity to its deep roots in Europe’s intellectual history, individualism, and the felt need to draw borderlines, it identifies the most important features used to mark off individual and collective identities, and demonstrates why they are deemed important. It concludes with a glimpse at the many ways in which literature has engaged with problems of identity throughout history.