This document defines and classifies different types of social media. It discusses blogs, social networks, microblogging, and podcasts. Social media are defined as internet applications that allow users to generate and share content. Key points include that social media enable interaction and sharing between individuals, communities and organizations. Different forms of social media are discussed, and Kaplan and Haenlein propose a classification scheme with seven types: collaborative projects, blogs, social news, content communities, social networks, virtual games, and virtual social worlds.