The article explores the sentiment analysis technologies , identifies key indicators in the analysis of the relationship between consumers and manufacturers. It also demonstrated the effect of  growing volume of Internet resources on mood and sales. We studied differing approaches of different categories of people towards the the same product and studied the interests of customers by tracking their inquiries on social networks through the NetBase Insight Composer platform. In the modern world, the business sector, as well as the advertising and marketing sector, are developing using the capabilities of information technology. Sentiment analysis has a special place in the development of online marketing sites and product sales through social networks, tourism sector, as well as development of other fields. Considering the importance of mood in relations between the parties, mood analysis methods were studied on Internet resources. It became clear that the application  of mood analysis methods played an important role in increasing the effectiveness of advertising and marketing. The study conducted in advertising and marketing field positively  influences the development of the economy. Scientific analysis of topical problems and their solutions, generalization of results and methods and methodologies of systematic approaches were used in preparation of the article. The results of the study show that application perspectives of sentiment analysis technologes must be studied in order to increase the effectiveness on adversiting and marketing on internet. great achievements can be obtained by focusing on local  online shopping sites, broadening buyer audience on advertising and marketing field can lead to development of economy  If its possible to purchase products on local sites , it is possible to prevent the flow of currency from the country, improve the quality of domestic marketand improve the welfare of the population (pp.116-124).