Il gruppo e la community - In these last decades the theme of the group is came back to the actuality also thanks to the coming of the world wide web. From this virtual world are arrived directly in our lifes new ideas, new sensations and new concepts. The aim of this work is to explore the knowledge of two word: the one old, the group, and the one new, the community. Thus, this paper shows some features common to both analyzed subjects: the group and the community. In fact we can find, after a careful study, similar words like: status, roles, leadership, nets of communication and other typical characteristics of them.