Zz-structures offer graph-centric views capable of representing contextual interconnections among different information. In this paper we use these structures in order to represent and visualize concept spaces in e-learning environments, and we present their formal analytic description in terms of graph theory. In particular, we focus our attention on the formal description of two views (H and I views), and we extend these notions to a number n > 2 of dimensions. We also apply both this formal description, and the particular properties of zz-structures, to an example in the Web-based education field.
