This book addresses the contribution of mathematics education to media literacy in general education schools. Related questions and concepts are analyzed constructively and critically, and illustrated with examples. The considerations are based on the premise that media are "tools for understanding the world." This concept of media is broader than previously defined in media education and differs from the almost exclusive perspective in mathematics didactics that focuses on the use of new media or digital tools as "technical media." Since media, as "tools for understanding the world," never provide us with reality itself but only with media-specific constructed and staged excerpts of reality, there is a demand for the promotion of "media awareness as an educational goal." This book is a plea for an active engagement with these topics.