The aim of this paper is to closely clarify when the first social networks appear in history, why mostly children and young people use them, as well as how and to which extent these0 social networks and media influence adolescent behavior. It is very important to understand the role of social networks in adolescent life. Today, this topic is very important precisely because the media has become widespread and is used several hours a day. From a pedagogical point of view, this topic is especially important because social networks and media need to modernize teaching and make it as interesting as possible. Educators, teachers, professors and parents should behave responsibly and teach adolescents about a responsible use of social networks. By a more detailed analysis, it can be concluded that social networks preoccupy both the younger generations and the elderly. This notion, of course, influences the behavior of new generations and their perception of the world around them. The need for media competence has reached its peak, and education cannot progress unless teachers and professors are primarily qualified and efficient in using the media in their classrooms. Of course, lifelong education, training and responsible usage of social networks can enhance teaching.