Semantics is
massively overloaded term in the field of Web, computer science and IT in
general. It originates from the humble ancient Greek philosophical scripts, and
points to the “meaning” of an entity (semantics corresponds to the modern Greek
work of 
) . In IT though, and in particular in the emerging Semantic Web, semantics has a
different connotation and mission: to encode the real world meaning of entities
in a computerised form that allow processing and automation and enables
(computer based) reasoning. This could enable computer systems to act
autonomously on our behalf, do things smarter, do more things, speed up
information consumption and management. Sceptics see all these as yet another AI
grandiose project, but think of the possibilities of semantic technologies
applied to everyday life: Googling for a specific term doesn’t always yield the
expected results (the naïve example of “Paris Hilton” as the Hotel chain in the
city of Paris versus the Hollywood socialite). If the computer had a way to
“understand” and distinguish between Paris Hilton referring to the Hilton Hotel
in Paris versus Paris Hilton the person, then search would be more productive
and effective. Semantics can help achieve that.
The above naïve example, is only a tiny fraction of what semantics can do. Their applications and promise spans across a multitude of domains. The most prominent modern promoter of semantic technologies, is the ambitious extension of the Web: Semantic Web. Originally conceived by TBL and his team, the Semantic Web attracted the interest and dedicated efforts of thousands of researchers and practitioners in its short 12 year history. The results are promising and proofing: Semantic Web technologies are used in one way or another in thousands of applications around us: from news feeding sites and weather widgets to financial markets stock brokering systems. However, their penetration and publicity is not on par with the popularity of Web 2.0 technologies. Statistically thinking, one in every two of you who read this page will be a member of some social networking site, hence, you will be enjoying the benefits of Web 2.0 technologies. But, there is no statistical evidence that one in every two who read this page will be familiar with Semantic Web technologies...
So, folks often ask me: “Where is the Semantic Web? Why can’t I see it or use it?”. Well, the answer is because the Semantic Web and its prominent technologies (OWL, RDF, SPARQL, etc.) are mostly used in the background by engineers who put up all those intelligent web sites. The truth is, unless you are dealing with engineering such things, you won’t experience Semantic Web technologies; at least not at the level that engineers do. Think of it as an analogy of Java and Javascript technology that powers up loads of interactions with your web browser. Does the end user get to see it? Or experience it by hacking Java code? Not really. But the end result is compelling: more tasks can be done on the Web now than 10 years ago. Equally, more things will be possible when Semantic Web technologies are in full strength and adopted widely.
Nevertheless, as with all technological innovations and breakthroughs, what matters is how and when they will be accepted and adopted by the society. For semantic technologies, and the Semantic Web in particular, here’s some areas where they promise to do better than technologies of today:
Better information access;
Better re-use and repurposing of data;
Semantic search;
Interoperability and integration.
Some of these are pure IT systems tasks that doesn’t mean much to the layperson, but looking at it from a different angle, these are the advancements that will enable unforeseen use of technology and spark new societal forms of communication and collaboration. If Web 2.0 is good for hundreds of millions of socially networked people today, then Web 3.0 will raise networking to a different level: more intelligent and personalised, more secure and productive, more proactive and customisable, more ubiquitous and mobile.