This document provides an overview of the Centers for Disease Control and Prevention's (CDC) use of Facebook and other social media platforms. It discusses CDC's strategy of using social media to disseminate public health information to diverse audiences. It highlights CDC's Facebook page which has over 54,000 fans, and the "i know" campaign page which focuses on HIV prevention among young African Americans. The document also outlines CDC's social media best practices around compliance, accessibility, and interaction with users.