The exponential growth of social media has transformed human interaction, providing unparalleled opportunities for communication, connection, and community formation. However, in addition to their advantages, social media platforms have also emerged as breeding grounds for disinformation, division, hate speech, and diminishing norms of digital civility. This chapter examines the intricate relationship between social media and civic responsibility, positioning digital civility as a contemporary extension of conventional civic norms. The text examines the psychological, sociological, and technological determinants that shape online behavior, encompassing anonymity, echo chambers, algorithmic biases, and performative activism. This chapter utilizes interdisciplinary research from communication studies, psychology, sociology, and digital ethics to analyze the origins and consequences of online incivility, highlighting its spillover effects into offline social and civic life. Strategies to promote digital civility such as digital literacy, ethical platform design, community standards, and regulatory interventions—are examined, emphasizing the need to balance free expression with harm mitigation. This chapter contends that digital civility transcends conventional etiquette, serving as a fundamental component of democratic society and civic responsibility in the digital era. To restore "the forgotten code" of civic responsibility, individuals, institutions, and governments must unite to transform the digital commons into environments that foster respect, empathy, and constructive discourse.