An accessible introduction to the technical and social construct of digital identity, this book helps students understand how the data they generate through online activities and apps is used and the implications it can have. Each of us has a digital identity, compiled of multiple identities, which has been built over the years as we have interacted with various technologies and apps. This book explores how the data generated through these online activities is used by third parties to form our digital identity and how this identity can then determine where we live, what job we have, what we buy, who we vote for, what healthcare we can access, and much more. Featuring real-world examples, discussion questions, and activities throughout, the book aims to help students understand the impact of their digital identity on everyday life. By understanding how technologies are used by apps, businesses, governments, and third parties, they can then begin to manage their digital identity and regain control of the way they are represented to the world. An important guide to digital identity for undergraduate students, this book will be especially useful to those studying topics such as big data and society, digital literacy, media and communication, social media and society, and beyond.