The rapid transmission of ideas, emotions, or behaviors between people in a group or society, similar to biological contagion. This phenomenon explains how a group of people can adopt a certain behavior or feeling almost simultaneously, without prior planning or centralized guidance, occurs through direct interaction or indirect observation. Social contagion emphasizes the ability of groups to promote emotions such as joy, anger, panic, or enthusiasm, as well as behaviors such as demonstrations, jubilation, participation in celebrations, or even aggressive actions. This phenomenon is based on the influence of the group on the individual and the partial loss of control over oneself under the influence of the crowd, as people become more inclined to imitate others or spontaneously engage in group behavior. Psychologically, social contagion is associated with concepts such as suggestibility, social mimicry, and emotional identification, in which people tend to adopt what they see or feel in their surroundings in order to strengthen group affiliation and reduce conflict with the group. Social contagion also suggests that collective behavior is the result not only of individual differences or personal motives, but also of the consistent interaction between people and the transmission of emotions and ideas between them. From a sociological point of view, social contagion plays an important role in explaining the rapid spread of social phenomena, be it fashions, trends, protests, or mass movements. It explains how a small group of people or a particular event can have a broad impact on a large group, expanding our understanding of how emotions and behaviors are transmitted between people and how group dynamics affect individuals.