The channels for expressing opinions seem to increase daily and hence, they are important sources of business insight. For product planning, marketing and customer service, it is necessary to capture and analyse these opinions. The social blogs are massive corpus for text and opinion mining. So, in this competitive and greedy world we find the need of analysis of the opinions about the products a vital task, to evaluate and improve the product quality, and as a result these opinions are relevant to companies. These opinions are easily accessed through the social blogs. This paper discusses various methods in performing sentiment analysis. We can see that presently we are provided facility to post the opinions in different languages and this paper tried to consider the processing of texts of different languages that are posted in blogs. Along with that the relevance of the quality of dataset used for the analysis are also the subject of discussion in this paper.