how digital texts are different from printed books
linkage of fragments and files of the same or different media types
multi or even non linearity of both text structure and individual reading
multimedia and animation of texts in the broadest sense
interactivity as a way for the user to intervene in the screen or database sets
interactivity as communication between different protagonists on the computer network
as a corollary of the two previous points, shifts in or even de-differentiation of traditional action roles such as author, reader and editor