Semantic Web Programming and Ontology Construction Courses
At present, information on the web is oriented towards human consumption. Computers are presently mainly used as means for storing and conveying that information. Humans understand the meaning of the information they are using, whereas, for a computer that information is just a large collection of symbols. In order for computers to be able to use web information they need some mechanism for understanding its meaning. This is the classical issue of information vs. knowledge. Knowledge permits reasoning and planning. As the web is a network oriented medium so, knowledge on the web can be envisaged as a net - in effect, a semantic network.
Web pages use markup in the form of HTML/XHTML. XHTML documents are based on XML,
XML itself has no mechanisms for representing semantic information.
After almost two decades of research there are now stable and robust technologies
for building semantic web applications.
The key technologies are
- RDF (Resource Description Framework)
- RDFS (RDF Schema)
- OWL (Web Ontology Language)
These are all based on XML.
The RDF approach is quite complex. For classical web sites and applications it would be much easier to provide semantic information via properties in HTML tags that contain semantic information. This, more recent initiative, has resulted in the development of RDFa, which is, in effect, a micro-annotation mechanism. RDFa is based on RDF. RDFa has great potential for organisations that need to provide easily accessible information such as local and central government departments and agencies, the NHS, etc..