The unrestrainable explosion of the world wide web is not bereft of troubles and drawbacks, especially for inexpert users. Therefore there is a strong need of new research approaches in term of theories and systems. The main objective of this book is to provide new tools and ideas to enhance the power of the internet and search engines. Among these new research trends an important role is played by technologies that enable to process imprecise information, and to perform approximate reasoning capability. This book written by leading experts in their field demonstrates the ability of Fuzzy Technology to exploit the tolerance for imprecision to achieve tractability, robustness, and low solution costs and it shows that soft computing methods are a good choice to face complex Web problems.