Social media is now a core part of how we communicate in today’s world. It is a rich source of user-generated content, reflecting public sentiments on various issues. This study will, therefore, undertake a critical analysis of methodologies employed in sentiment analysis on social media data and their applications in multiple domains like product reviews. The upsurge of social media has gone up dramatically on platforms like Twitter and Reddit, among others. It has filled the web with user-generated content, and therefore, sentiment analysis will be very much valuable in truly understanding the opinion of the public. This study proceeds further with the exposition of the various tools, technologies, and methodologies through which sentiment analysis is done, underlining NLP and machine learning techniques as crucial elements in this respect. It will also enable the researchers and practitioners to select appropriate models and techniques that shall yield the most effective and realistic sentiment analysis, thereby enabling better decision-making processes by industries to address and meet customer expectations effectively.