The document discusses how to make content go viral through math and split testing. It defines going viral as rapid sharing online and measures virality through a content's K-factor, which is the product of invitations sent and conversion rate - a K-factor over 1 indicates growth. It recommends engineering content to boost user engagement by increasing social login, automatic login, notifications, and shareable events. Finally, it outlines six factors (STEPPS) and strategies to encourage sharing, including incentives, easy sharing tools, emotional triggers, and ego appeals.