Abstract
This paper describes an ongoing research project in the area of electronic books. After a brief overview of the state of the art in this field, two new forms of electronic book are presented: hyper-books and visual-books. A flexible environment allows them to be produced in a semi-automatic way starting from different sources: electronic texts (as input for hyper-books) and paper books (as input for visual-books). The translation process is driven by the philosophy of preserving the book metaphor in order to guarantee that electronic information is presented in a familiar way. Another important feature of our research is that hyper-books and visual-books are conceived not as isolated objects but as entities within an electronic library, which inherits most of the features of a paper-based library but introduces a number of new properties resulting from its non-physical nature.