This academic work examines the intersection of social movements and internet technology in contemporary society. Written by Fabien Granjon, the book analyzes how digital networks have transformed collective action and political engagement. Drawing on sociological research, it explores the ways activists and social movements have adopted and adapted internet technologies for organizing, communication, and mobilization. The study covers both theoretical frameworks and practical applications, considering the broader implications for democracy and civic participation in the digital age. Published in 2001, this early analysis of internet activism provides valuable insights into the evolution of online political engagement and the relationship between technology and social change.