Common NLP tasks and techniques. Sentiment analysis

Sentiment analysis, also known as opinion mining, is the process of determining the attitude or emotion of the writer towards a particular topic. Sentiment analysis is used in a wide range of applications, such as market research, brand management, and political analysis. There are several techniques used in sentiment analysis, including lexicon-based methods, which use a predefined list of words and their associated sentiment, and machine learning-based methods, which use algorithms to learn patterns in the data. Text classification is the process of automatically categorizing text into predefined categories or labels. Text classification has a wide range of applications, including spam detection, sentiment analysis, and topic classification.