Online social dynamics encompass the patterns and processes through which individuals and groups interact, communicate, form relationships, exchange information, and influence one another through digitally mediated environments ^[1][2]. They include changes in social networks, interpersonal ties, group formation, social norms, collective behaviors, and patterns of information diffusion that emerge through online interactions ^[3]. These dynamics are shaped by users’ behaviors and relationships as well as by the technological features and affordances of digital platforms, including mechanisms for communication, content sharing, recommendation, and network formation ^[4]. Online social dynamics may operate at both individual and collective levels, with interactions among users contributing to broader patterns such as community formation, social influence, cooperation, conflict, or polarization. The dynamics may also evolve over time as users, relationships, information, and platform environments change. Online social dynamics therefore encompass the ongoing interactions and transformations that characterize social life in digitally mediated environments.