Abstract
The amount of the available data increases the ability to analyze and understand. The internet revolution has added billions of customer’s review data in its depots. This has given an interest in sentiment analysis and opinion mining in the recent years. People have to depend on machines to classify and process the data as there are terabytes of review data in stock of a single product. So that prediction customer sentiments is very important to analyze the reviews as it not only helps in increasing profits but also goes a long way in improving and bringing out better products. In this paper , we present a survey regarding the presently available techniques and applications that appear in the field of opinion mining , such as , economy , security , marketing , spam detection , decision making , and elections expectation.