The growth of Internet allowed the emergence of new spaces of exchanges and social interaction between remote individuals. These new modalities of social interactions led the researchers, in the framework of Computer-Mediated Communication (CMC), to study the social component of online exchanges, characteristics and consequences of this type of interaction. In this perspective, the aim of this work is to examine how the characteristics of CMC - first anonymity - can modulate social perceptions and the processes involved in online interactions. This problem concerns many communication situations and involves different processes. Accordingly, the present work is organized in three research areas. The first part deals with the study of perceptions based on membership confined to a virtual environment. The second part focuses on the asymmetric modulation of gender perceptions on the Internet. The third part examines the influence of social norms and possibilities of expression in the CMC. Taken together, the results suggest that the CMC does not induce a weakening of social factors, but a modulation of the processes according to the characteristics of the context of interaction. The results are discussed in the light of the social identity theory, the self-categorization theory and the SIDE model.
