Social marketing is defined as using marketing principles and techniques to influence voluntary behavior change for social good. It involves understanding target audiences, developing socially beneficial products and messages, and disseminating these through appropriate distribution channels. The document outlines the evolution of social marketing from commercial marketing, its objectives and principles, applications, and differences from commercial marketing. Recent developments highlighted include its use in health promotion, injury prevention, and community mobilization through approaches like social franchising and tailored messaging to segmented populations.