Lee Feigenbaum of CMSWire has written an article discussing the "what" and "why" of semantic web technologies. He writes, "In my first article on The Semantic Web and the Modern Enterprise, I introduced the vision of the Semantic Web. I also discussed how the progress made while working towards that vision provides a strong foundation to help enterprises better deal with their information management challenges. In this article, we’ll take a high-level look at what the core Semantic Web technologies are, why they’re different from conventional technology approaches and how they deliver tangible benefits for enterprise information management."
He begins, "Semantic Web data is represented using a technology standard called Resource Description Framework (RDF). RDF is a graph (web-like) structure that links data elements together in a self-describing way. RDF is perhaps best understood in contrast to how enterprise information has traditionally been represented for the past 30 years — relational databases. Relational data is stored in tables, and the meaning of a particular piece of data is dependent on the particular table and column it lives in. Details about the table and column, such as its name, its definition and acceptable values, are kept in a dark corner of the database known as the catalog. This information is difficult to access and is not directly linked to the data itself. In practice, this means that software that accesses relational data needs to have the meaning of the data hard-coded into it."
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