Chapter 12. RDF
The Resource Description Framework (RDF) is a proposal for consistently encoding metadata in an XML syntax. The grand idea behind RDF is the creation of the Semantic Web. If everybody were to cre- ate RDF describing their content, then computers would be able to find relationships between documents that humans would not necessarily discover on their own. At first glance, the syntax will seem a bit overwhelming, but it is not that difficult. Really.
RDF is very much like the idea of encoding meta data in the meta tags of HTML documents. Using the HTML model, meta tags first define a name for the meta tag, say, title. Next, the content attribute of the HTML meta tag is the value for the title, such as Gone With The Wind. For example, the following meta tag may appear in an HTML document: <meta name="title" content="Gone With The Wind"/>. These name/value pairs are intended to describe the HTML document where they are encoded. HTML docu- ments have URL's. These three things, the name, the value, and the URL form what's called, in RDF parlance, a triplet. RDF is all about creating these triplets; it is all about creating name/value pairs and using them to describe the content at URLs.
It is not uncommon to take advantage of the Dublin Core in the creation of these name/value pairs in RDF files. The Dublin Core provides a truly standard set of element names used to describe Internet re- sources. The fifteen core element names are: