Next Generation Wireless Applications: Creating Mobile Applications in a Web 2.0 and Mobile 2.0 World, 2nd Edition

5.8 SEMANTIC WEB

We have looked at how the Web is a major networking force today, not only for human-centric uses where visualisation of information is important, but also for application-centric uses where basic exchange of information enables physically separate applications to collaborate.

Most of the content on the Web today has human consumption in mind and therefore the semantic meanings of the web pages are what their visual form conveys implicitly. For example, a web page displaying a photo album only means something to a person who knows what the pictures contain and to whom the content has relevance and this information about the photo album is only available visually. An appointment in a web-based events diary only has meaning to a person who knows what the event is about and to whom it is relevant. In other words, the meaning of information on the Web is usually conveyed by whatever is visibly evident on the page. Furthermore, these meanings are only accessible to human consumers, not to applications running on machines, because only humans, not machines, can see the pages.

It would be useful if applications could understand the meaning of information on the Web. For example, we might want to search the Web for news information relating to a particular field of interest. Probably, whenever we look at a news item on a page, we know that it is news. We can tell by certain formatting and context, even if the word ‘news’ is not itself displayed on the page. However, we ...