The document introduces the topic of online social networking. It provides several definitions of social networking, including expanding business and social contacts through connections with other individuals, groups of people drawn together by common interests, and online services that allow users to interact and share interests. Examples of social networking sites mentioned are Twitter, LinkedIn, Facebook, and Ning. The document then shifts to discussing social networking as a tool for learning, noting that study groups can help students clarify uncertainties, improve understanding by answering each other's questions, and benefit from taking on a teaching role to others.