E-learning leads to evolutions in the way of designing a course. Diffused through the web, the course content cannot be the pure transcription of a face to face course content. A course unit can be seen as an organization in which different actors are involved. These actors produce documents, information and knowledge that they often share. Within the MEMORAe project we design an ontology-based document-driven memory which we think as being particularly adapted to an e-learning situation. We precise the choice of the Topic Maps formalism that we use for knowledge representation.