The book "Multimedia Semantics - The Role of Metadata" offers a comprehensive analysis of the challenges and opportunities in the field of multimedia metadata. It is aimed at professionals and enthusiasts who wish to engage with the fundamental questions surrounding multimedia metadata. The focus is on providing contextualized, accessible, and interoperable services at a higher semantic level. The authors, Michael Granitzer, Mathias Lux, and Marc Spaniol, present a selection of foundational articles that serve as a basis for research in the area of multimedia metadata. Additionally, the current state of research in this dynamic field is highlighted, covering various application domains such as broadcasting, interactive television applications, e-learning, and social software. The book is the result of collaboration within the multimedia metadata community, bringing together experts from research and industry, thus making a valuable contribution to the development of innovative products.