“Contagious: How to Build Word of Mouth in the Digital Age” by Jonah Berger

"Contagious" by Jonah Berger explains why some ideas, products, or messages spread widely while others don't. Berger identifies six key principles—Social Currency, Triggers, Emotion, Public Visibility, Practical Value, and Stories—that make content more shareable. The book emphasizes that understanding these factors can help businesses and individuals craft messages that naturally generate word-of-mouth and become popular in the digital age. Through engaging real-world examples, Berger shows how harnessing these principles can increase influence and drive growth by making ideas more memorable, relatable, and easy to talk about.