Hate speech manifests itself in different social contexts, such as political debates, artistic expression, professional sports, or work environments. However, the rapid development of digital technologies, and especially of social media platforms, has created additional challenges to understanding this extreme act. This book explores the nature of hate speech on social media. Readers will find chapters written by 21 authors from 18 universities or research centers. It includes researchers from 11 countries, prioritizing a diversity of approaches from the Global North and Global South – Brazil, Cyprus, Ethiopia, Germany, Nigeria, Portugal, South Africa, Spain, Switzerland, Turkey, and the USA. The analyses herein involve the realities in an even larger number of countries, given the transnational approach of some of these studies.