Through this issue, we propose to examine five types of legitimation processes. There is the legitimization, and hence the canonization, of works by complex intertextual relations; for circulating a work is largely a matter of putting it in the collective memory. One can also want to legitimize an emerging artistic practice or form, with rhetoric reinforcing with legitimating bodies: this was the case, for example, with cinema as "filmed theater" and a century later with video games as "interactive cinema". ". A third process of legitimization is perhaps more the result of the digital revolution: the decline of the "legitimate" culture, which is steadily declining in the face of the proliferation of sub-cultures that are at the same time more segmented but hyper-accessible. There is room for a fourth process of legitimization rooted in the popularization of textual figures or formal mechanisms previously reserved for marginal productions. The balance of power between the Institution and the many popular authorities is reversed and the cultural hierarchy dissolved. The fifth process of legitimation is one that is carried out in spite of itself: to gather cultural artifacts in one place, even if they have no stylistic coherence, tends towards an "official" comprehension of these artifacts.