What is sentiment analysis? Using NLP and ML to extract meaning

Sentiment analysis is analytical technique that uses statistics, natural language processing, and machine learning to determine the emotional meaning of communications. Companies use sentiment analysis to evaluate customer messages, call center interactions, online reviews, social media posts, and other content. Sentiment analysis can track changes in attitudes towards companies, products, or services, or individual features of those products or services. One of the most prominent examples of sentiment analysis on the Web today is the Hedonometer, a project of the University of Vermont's Computational Story Lab. The group analyzes more than 50 million English-language tweets every single day, about a tenth of Twitter's total traffic, to calculate a daily happiness store.