The document summarizes the use of social media during disaster events. It discusses how social media is used for collaboration, expressing gratitude and grief, and sharing experiences during crises. It provides examples of how government agencies and organizations used social media before and after Hurricane Sandy to plan, respond to, and recover from the storm through information sharing and situational awareness. Key metrics on social media mentions and photos related to Sandy are presented to demonstrate the scale of engagement on platforms like Twitter, Facebook, Instagram and Foursquare. The importance of verifying information before sharing on social media is emphasized.