Does the so-called media society consist of well-informed citizens? Does the availability of the internet lead to a reduction in knowledge disparities? This volume provides a well-founded, concise, and illustrative introduction to the theoretical foundations, methodological approaches, empirical findings, and societal contexts of knowledge gap research. It starts from the premise of growing knowledge disparities between higher and lower status groups due to media information dissemination and is currently expanding with research related to the digital divide concerning the internet. The introduction serves as a solid entry-level reading for scholars, as a textbook for students, and as an overview for those interested in societal issues.