Research in the field of multimedia metadata is especially challenging: Lots of scientific publications and reports on research projects are published every year and the range of possible applications is diverse and huge. This book gives an overview on fundamental issues within the field of multimedia metadata focusing on contextualized, ubiquitous, accessible and interoperable services on a higher semantic level. The book in hand provides a selection of basic articles being a base for multimedia metadata research. Furthermore it presents a view on the current state of the art in multimedia metadata research. It provides information from versatile applications domains (Broadcasting, Interactive TV, E-Learning and Social Software) such as: Multimedia on the Web 2.0 - Databases for Multimedia (Meta-)Data - Multimedia Information Retrieval and Evaluation - Multimedia Metadata Standards - Ontologies for Multimedia. The multimedia metadata community (www.multimedia-metadata.info), wherefrom this book originated, brings together experts from research and industry in the area of multimedia metadata research and application development. The community bridges the gap between an academic research and an industrial scale development of innovative products. By summarizing the work of the community this book contributes to the aforementioned fields by addressing these topics for a broad range of readers.