Social media is one of the significant places to show user's feelings. In sentiment analysis the information is separated from the notion, assessment and feelings of individuals with respect to entities, events, and their characteristics. Sentiment analysis is also known as Opinion Topic Modeling (OTM) approach. OTM is used to examine and group the user created information likecomments, articles and so on. Thisinformation's are taken from the social networking sites like facebook, twitter and so on. Twitter has given a huge space for analysing movie reviews, consumer brands, election events, stock market exchange, and so on. This survey paper discusses several methods used for sentiment analysis.