An overview of Semantic Web activities in the OMRAS2 project Gy¨ orgy Fazekas † 1 , Yves Raimond 2 , Kurt Jacobson 1 , and Mark Sandler 1 1 Queen Mary University of London, Centre for Digital Music 2 BBC Future Media & Technology Abstract The use of cultural information is becoming increasingly important in mu- sic information research, especially in music retrieval and recommendation. While this information is widely available on the Web, it is most commonly published using proprietary Web APIs. The Linked Data community is aim- ing at resolving the incompatibilities between these diverse data sources by building a Web of data using Semantic Web technologies. The OMRAS2 project has made several important contributions to this by developing an ontological framework and numerous software tools, as well as publishing music related data on the Semantic Web. These data and tools have found their use even beyond their originally intended scope. In this paper, we first provide a broad overview of the Semantic Web technologies underlying this work. We describe the Music Ontology, an open-ended framework for com- municating musical information on the Web, and show how this framework can be extended to describe specific sub-domains such as music similarity, content-based audio features, musicological data and studio production. We describe several data-sets that have been published and data sources that have been adapted using this framework. Finally, we provide application examples ranging from software libraries to end user Web applications. Introduction From the management of personal media collections to the construction of large content delivery services, information management is a primary concern for multimedia-related tech- nologies. However, until recently, solutions that have emerged to solve these concerns were existing in isolation. For example, large online databases such as Musicbrainz 1 , encyclopedic sources like Wikipedia 2 , and personal music collection management tools such as iTunes 3 or Songbird 4 do not interact with each other, although they can deal with similar kind of † Correspondence should be addressed to gyorgy.fazekas@eecs.qmul.ac.uk. 1 http://musicbrainz.org/ 2 http://www.wikipedia.org/ 3 http://www.apple.com/itunes/ 4 http://www.getsongbird.com/