Guest editors' introduction: Emerging internet technologies for e-learning

As a flourishing field, e-learning at large (including distance learning, Web-based learning, and digital game-based learning) has attracted increasing attention from both industry and academic sectors. To facilitate the development of effective e-learning systems, scalable technologies that support an arbitrary number of users while providing them with a good learning environment are needed. In this introduction, we provide an overview of e-learning system development with respect to a layered reference architecture, including the Internet infrastructure layer, the conceptual/modeling layer, and the application layer. In addition, the three articles included in this special issue cover the issues of managing the learning objects in an open and scalable architecture, incorporation of learners' pedagogical features in Web-based learning environments, and support of digital game-based learning. All these issues, though not exhaustive, are important to ensure successful development of e-learning systems on an Internet platform. © 2009 IEEE.