Semantics, as defined in Wikipedia:

Semantics is the study of meaning, usually in language. The word “semantics” itself denotes a range of ideas [...]. It is often used [...] to denote a problem of understanding that comes down to word selection or connotation.

The Semantic Web is an extended web, with a greater meaning, in which users will be able to find answers to their questions faster and easier due to a better-defined information. This meaning-based web is supported by a set of standardized  languages that solve the problems the semantic-less web has, in which access to some information is a difficult and frustrating task.

The web has changed the way we communicate and do our work. Worldwide low-cost instantaneous communication is possible nowadays. We have access to millions of resources, regardless of our geographic location or language. These features have made the web tremendously successful… and at the same time they have provided its biggest problems: information overload and heterogeneity of information sources.

The Semantic Web aims at solving these two great problems, allowing software to perform some of the tasks the user must take care of now. Thanks to semantics in the web, software can process its contents and make logical decisions to solve everyday problems automatically.

Imagine you would want to find the nearest open pharmacy. You would go to your favorite web search engine and type “pharmacies open right now”. Today’s search engines would offer different information about pharmacies, but nothing related to what the user exactly wants to know. The next step would be to go through all the options listed and manually search for the precise information. Figure 1 shows the results a user would get with a regular search engine today.

By building semantics into the core of the web the search results would be accurate. Software would be able to properly understand what the user is asking for. Figure 2 shows results with a semantic search engine. These results give the user the exact information he was looking for. Geographic location would be detected automatically, and words like “right now” acquire greater sense and get translated to today’s date. All the information would be full of meaning.

The way information will be processed won’t be based on input/output parameters, but on its semantics. The Semantic Web provides an infrastructure based on metadata, allowing software to reason on the web, extending its capabilities.

It’s not about a magical artificial intelligence that will enable machines to understand human words… it’s just the skill of a machine to solve well-defined problems through well-defined operations that will be performed on a well-defined data set.

Further reading

This article covered just the very basics of the Semantic Web. If you’re still interested, you can expand your knowledge at:

• Semantic Web
• Web Ontology Language
• semanticweb.org
• Swoogle: experimental semantic search engine (if you’re going to use this, you might as well be interested in the FAQ)