Information for motorway users. What type of information? For what purpose? L'information des usagers sur autoroutes. Laquelle? Pour quoi faire?

The results of discussions and studies on the information needed by motorway users and how to provide it are presented. The main functions of the information are analyzed through the advantages demonstrated by the designers and the usable systems. This work forms part of an overall discussion on the various problems arising from the development of highway information.