Editorial

Widely available learning material is recognized as a key asset that enables aggregation, provisioning, retrieval, reusability, adaptation, and personalization of educational content. Besides being able to author, publish, discover, and use high- quality learning objects, it is equally important to use multimedia-rich learning objects. Many domains require very advanced content, where different concepts and processes require the use of multimedia (e.g. image, sound, and video) to provide students with a better understanding of concepts under study. This inevitably sets new requirements in multimedia-enhanced learning environments for the advanced representation and creation of learning metadata. The goal is not only to have a richer representation of learning content but it is also important to consider multimedia learning objects in various learning situations where interaction and collaboration are required features.