The document discusses how social media sites like Twitter, Facebook, and YouTube are popular among students and how instructors can tap into these tools for online classrooms. It provides an overview of how to get started on Twitter, such as setting up a profile and account, posting tweets, following and being followed by others, and using hashtags. Tips are offered on how instructors can use Twitter to share course-related information, network with others in their field, and engage with students. Various Twitter apps and tools are also highlighted.