Exploring the Semantic Web with Dr. Watson
It was another oppressively muggy day in London, and Sherlock Holmes and Dr.Watson were lazily discussing a shocking new discovery. “Great Scott, Holmes, ” Watson exclaimed, “they’ve gone and named an Alternative Search Engine after me! But what in the blazes is an RDF? And what do they mean by the Semantic Web?
“Elementary, my dear Watson,” Holmes replied as he reached for his laptop. He navigated to Answers.com. “Here’s your answer.”
RDF: A recommendation from the W3C for creating meta-data structures that define data on the Web. It is designed to provide a method for classification of data on Web sites in order to improve searching and navigation.
RDF is based on XML
RDF is implemented in XML (RDF/XML) and adds new rules to XML as well as reducing some constraints. For example, it supports flat structures, eliminating the need to have data nested in a hierarchy. RDF is structured as one or more Triples: (1) the subject (what the data is about), (2) the property (an attribute of the subject) and (3) the actual value.
RDF is a common denominator
RDF serves as a common denominator that allows different sets of vocabulary to be recognized. For example, using the RDF descriptor for zip code would let systems exchange zip code data that use “ZIP” and “ZIPCODE. See XDI and RSS.
“I’m afraid that’s just a bit over my head, dear fellow. After all, I’m a doctor, not an engineer!” “Here,” Holmes handed Watson a large piece of scrap paper that he had been doodling on, “perhaps this chart will help you.”
Watson’s face was flushed. “But what the devil has all this got to do with me? Where do I come in?” Clearly the good doctor was becoming exasperated.
“Because, my good man, it says right here,” Watson is a gateway for the Semantic Web, which has been guided by the requirements of Semantic Web applications and by lessons learnt from previous systems. Watson exploits the strengths of semantic technologies to provide fundamental functionalities for a more suitable access to online knowledge.
“There now,” Holmes asked, turning away from the screen, “do you understand now, Watson?” Watson’s chair was empty; Holmes was alone in the room! Downstairs he heard the faint thud of the front door slamming shut. “Watson? Watson?”
