A technique widely used today Hypertext encompasses a particular aspect of the virtual book that is playing an increasingly important part with the expansion of the Internet and the web. The success of HTML (HyperText Markup Language) – attests to its dynamism. Nowadays it seems so natural and so usual that we manipulate it with ease and we discover its ancestors among medieval cabalists or among other commentators of sacred texts. Every indexation, every note and every comment suggest a potential rudimentary hypertext. However, before its expansion over the entire planet, with the network of worldwide telecommunication, before being programmed on to every PC, hypertext took form in the minds of a few learned visionaries. We will refer to two of them.