Introduction

Abstract

TheWeb was invented in the early 1990’s by Tim Berners-Lee to facilitate information sharing among scientists [101]. It wasn’t until 1993 when theWeb suddenly became widely known among the public, thanks to the release of aWeb browser called Mosaic. Mosaic was made available to the average user and quickly captivated the imagination of the public about the Web through its intuitive graphical user interface. Governments, businesses and individuals realized the great potential of the Web and took advantage of its growing popularity by making their data and applications Web accessible. Although started as a repository of information containing merely text and images, the Web has since evolved into a host of both multimedia information and service-providing applications. These applications range from map-finding to weather-reporting to e-commerce. Some of the applications involve, in real-time, hardware devices such as temperature sensors and traffic monitoring cameras. Businesses and governments realized that by integrating existing Web applications, they can provide value-added services that were previously unavailable. Unfortunately, the customized interfaces required to access these applications and the lack of semantics in the data they consume and generate have made the seamless integration of these applications and quick deployment of value-added services a daunting challenge.