The document provides an overview of social media 101. It defines social media as digital tools for sharing and discussing information between people. It discusses how social media spreads information through trusted networks in an exponential and self-reinforcing way. The key actions of social media are connecting, curating, and contributing. Social media is a powerful tool for behavior change by addressing individuals, relationships, communities, and societies. The document also discusses how government agencies can leverage social media agreements to engage with the public and provides an example of the National Cancer Institute's social media strategy around pregnant smoking cessation.