Recent developments and new directions in education have emphasised learners' needs, profile and pedagogical aspects by focusing on learner-centered approaches in educational settings. e-Learning, on the other hand, guarantees learners the opportunity of learning in their own way, and leads to new considerations in course design. e-Learning is defined as the new form of learning, rather than the use of new technologies. It requires new considerations in educational aspects and delivery methods. Personalised technologies and new approaches such as the use of ontologies and Semantic Webs in e-learning are some of the next challenges for both education and society in the future. This paper provides an overview and rationale for personalised web-based learning and personalised technologies. Also, it presents ontologies by emphasising the various usages of this term in a variety of fields, the main ontology structures, methodologies and design principles, and its applications in education.