Contagious: Why Things Catch On

Jonah Berger examines the mechanics of social transmission to explain why certain products and ideas gain public visibility while others fail. He introduces the STEPPS framework, which identifies six specific drivers of virality: social currency, triggers, emotion, public visibility, practical value, and stories. The book disputes the notion that advertising budgets or high-quality visuals are the sole causes of popularity. Instead, it uses case studies of viral YouTube videos, steakhouse marketing, and health initiatives to demonstrate how psychological triggers and narrative structures compel people to share information within their social circles.

This book serves marketing professionals, public policy advocates, and small business owners who operate without large promotional budgets. Readers gain a functional toolkit for engineering word-of-mouth growth and increasing the shareability of their content. By applying the STEPPS principles, they learn to identify specific elements that turn casual observers into active messengers. The text provides a systematic approach to word-of-mouth communication, offering readers the ability to predict and influence the spread of information across different demographics and digital platforms.