This thesis looks at YouTube at the level of the system that manages interactions with the user. YouTube as a social network is popular and used by adolescents. Considering that they are in a specific and risky development period, they are more susceptible to the influence that YouTube has at the system level. This alone makes them more susceptible to YouTube shaping their critical thinking process. This influence of YouTube at the system level will be observed through selected implicit factors of YouTube (filter bubble, virality, cancel culture). The goal of the research is to analyze the experiences and opinions of adolescents on the YouTube platform to understand the manifestation of the influence that the implicit factors of the YouTube social network have on shaping the process of their critical thinking. This empirical research is qualitative in nature. The data collection method was an interview. Ten respondents between the ages of fifteen and eighteen who regularly use the YouTube social network participated in the research. The results of the research showed that the selected implicit factors of YouTube significantly influence the shaping of the critical thinking process of adolescents, that is, the way in which adolescents interpret, analyze, evaluate, conclude and explain the information and content they encounter on YouTube, as well as their processes of self-regulation, self-examination and self-corrections. This influence mostly inhibits the process of critical thinking in adolescents. The results show the superficial and insufficient previous formal media education of adolescents, which did not help them in using the YouTube social network. Therefore, the importance of media education of adolescents was highlighted.