In order to scrutinize or evaluate an extremely high quantity of an ever-present and diversified nature of data, new technologies are developed. With the application of these technologies, called big data technologies, to the constantly developing various internal as well as external sources of data, concealed correlations between data can be identified, and promising strategies can be developed, which is necessary for economic growth and new innovations. This chapter deals with the analysis of the real-time uses of big data to both individual persons and the society too, while concentrating on seven important areas of key usage: big data for business optimization and customer analytics, big data and healthcare, big data and science, big data and finance, big data as enablers of openness and efficiency in government, big data and the emerging energy distribution systems, and big data security.