This article examines the relevance of the reasoning in various theses concerning the digital divide, by focusing on their underlying hypotheses. Four main versions of the digital divide are identified in the economic literature. The first explores economic and social inequalities related to access to equipment and infrastructures. The second imputes digital divides to use of ICTs by individuals and social groups. The third concerns the efficiency of use: for the same level of equipment, certain countries or individuals enhance their performance faster than others. The fourth definition relates more to the modalities of learning in a knowledge-based economy. As soon as information and knowledge become abundant, ICTs may be at the origin of many inequalities related to changes in learning processes and hence to performance. The author links up the different facets of these digital divides in a general model based on the logistic curve.