Sentiment Analysis: A Perspective on its Past, Present and Future

The proliferat ion of Web-enabled devices, including desktops, laptops, tablets, and mobile phones, enables people to communicate, participate and collaborate with each other in various Web communit ies, viz., fo ru ms, social networks, blogs. Simu ltaneously, the enormous amount of heterogeneous data that is generated by the users of these communities, offers an unprecedented opportunity to create and emp loy theories & technologies that search and retrieve relevant data from the huge quantity of information available and mine fo r opinions thereafter. Consequently, Sentiment Analysis wh ich automat ically extracts and analyses the subjectivities and sentiments (or polarities) in written text has emerged as an active area of research. This paper previews and reviews the substantial research on the subject of sentiment analysis, expounding its basic terminology, tasks and granularity levels. It further gives an overview of the state-ofart depicting some previous attempts to study sentiment analysis. Its practical and potential applications are also discussed, followed by the issues and challenges that will keep the field dynamic and lively for years to co me.