Purpose: The study's main goal is to find out how social media affects people's purchasing decisions and to look at how different factors affect how social media affects people's purchasing decisions. Design / Methodology: The objectives were met through the use of regression, factor analysis, t-tests, and descriptive statistics. This is a practical study based on a sample of 132 internet buyers in the Chennai district. The convenience sampling approach was used in this investigation. Findings: The study discovered six factors: information, entertainment, incentive, consumption, trust, and satisfaction. Each of the prominent online media occupations, such as data entertainment, incentive, consumption, trust, and contentment, has a substantial impact on customer purchasing behaviour. According to the average value of the roles, social media's function in influencing purchase behaviour was the most important, followed by information and incentives. The consumption factor played the least important role. This research might aid online businesses and website developers in efficiently using the social media platform to battle competition.