Social networking sites (SNSs) have changed the communication, interaction, and social identity development of adolescents in recent years. Social media like Instagram, Facebook, Snapchat, and X have become a part of teens' life, which affects their behavior, attitude and lifestyle. This study analyzes the influence of social networking sites in the behavior of adolescents in a positive and negative way. The study examines the impact of the use of SNS on communication skills, academic performance, self-esteem, social relationship and emotional health. Social networking sites can provide learning, self-expression, information sharing and social connection, but they can also provide distraction, cyberbullying, social isolation, anxiety and reduced academic engagement. The study is descriptive and analytical with the use of primary and secondary data to gain insights into the patterns of SNS use, and the behavioral implications of these patterns, among adolescents. The results indicate that social network sites have a notable effect on the behaviour of adolescents, and this effect varies according to the frequency and goal of the social network use, as well as personal characteristics. The study emphasizes the need for responsible and balanced use of social media and calls for increased involvement of parents, educators and policymakers in fostering digital literacy and positive social media behaviors among young people.