Article Hu, M., & Liu, B. (2004, July). Mining opinion features in customer reviews. In AAAI (Vol. 4, No. 4, pp. 755-760). 5 http://www.aaai.org/Papers/AAAI/2004/AAAI04-119.pdf Feature based opinion summarization is performed in two steps: Identify the features of the product that customers have expressed opinions on (called opinion features) and rank the features according to their frequencies that they appear to review Identify for each feature how many customer reviews have positive or negative opinions. The opinion summarization system consists of: Paper proposes techniques for mining opinion features from product reviews based on data mining and natural language processing methods.