Open Educational Resources (OER) emerged almost 15 years ago providing a framework of policies, adoption strategies, pedagogical practices and technological infrastructures to facilitate the reuse of resources among teachers from the local to the global level. In this paper a brief analysis of the main definitions and applications of OER from a technological perspective is introduced. The presence of the subject in the main journals and conferences within the framework of the IEEE is presented in a bibliographic review within IEEE Xplore Digital Library. Finally, future challenges facing OER within the areas of capacity building, cultural issues, access and quality, sustainability models and policies are described.