What is Ubiquitous Computing Systems

The actual mobile technology and the increasing need to obtain rich multimedia content about each and every aspect of the human life are changing the approach of the users to the World Wide Web. Indeed, the pervasive use of mobile devices and the heterogeneity of the provided services and information make the accessibility and usability of the Web resources a hard assignment. In particular two main tasks have been identified as focal issues, the first one regards the choose of a suitable model to express the complex activities of the Web (context modeling approaches), and the second one regards the translation of the different schemas, representing these Web activities, in a more suitable, manageable and standardizing schema. In this chapter we will present the problems related to the modeling of context data, and we will describe the actual and future approaches of Context Modeling according to the mobile devices world.