At this moment, data deluge is continuously producing a large amount of data in various sectors of modern society. Such data are called big data. Big data contain data originating both in our physical real world and in social media. If both kinds of data are analyzed in a mutually related fashion, values which cannot be acquired only by independent analysis will be discovered and utilized in various applications ranging from business to science. In this chapter, modeling and analyzing interactions involving both the physical real world and social media as well as the technology enabling them will be explained. Data mining required for analysis will be explained in Part II.