"[The author] shows how the same technologies that have bred negativity can also be mobilized as an exponential force for good, to create chain reactions of generous behavior. Every day, remarkable stories of individual acts of kindness have sparked remarkable ripple effects when shared online, achieving a level of impact never before possible. This book captures some of the most inspiring such stories, revealing their potential to solve problems and make people happier in the process. [The author] offers readers a playbook to fine-tune these actions, to take generosity from invisible to transformative"--Provided by publisher.