The Semantic Web

For those of you who read last month's article on Web 2.0, I promised I would continue this month with Web 3.0.

To recap, Web 2.0 defines the guidelines and principles of design specifications. Web 3.0 will continue on with the design specs of Web 2.0 but touch upon other areas of the web as well.

To start, Web 3.0 is now called "Semantic Web", a phrase coined from the World Wide Web consortium (or W3) which was founded by the inventor of the World Wide Web, Tim Berners-Lee. The W3 creates specific organizational guidelines for web developers and designers to maintain uniformity. Calling it the next step in web evolution, Berners-Lee defines the Semantic Web as "a web of data that can be processed directly and indirectly by machines." Now Web 3.0 is beginning to rear its head in how we manage online applications to assimilate data for various relationships. The word semantic stands for "the meaning of". The semantic of something is the meaning of something.

In the Semantic Web, data itself becomes part of the Web and is able to be processed independently of application, platform, or domain. The World Wide Web contains virtually boundless information in the form of documents. We can use our computers to search for these documents, but they still have to be read and interpreted by humans before any useful information can be extrapolated. Computers can present you with information but can't understand what the information is well enough to display the data that is most relevant in a given circumstance. The Semantic Web, on the other hand, is about having data as well as documents on the Web so that machines can process, transform, assemble, and even act on the data in useful ways.

For example, let's say you are an IT developer assigned a project using Ajax and SOAP web-based services. If you searched for "soap" you'd most likely find information on detergents and cleaning agents before you find other terms that relate to your project. After experimenting with various key words and phrases, you will eventually stumble on information you are actually looking for. In the future world of Semantic Web, you will be able to search for SOAP as it applies to technology and quickly be able to find what you are looking for.

So Semantic Web will, in fact, include manageable methods for locating data by association. Semantic Web will be based on studies of how we use the web now and better ways to manage the onslaught of data to fit into our everyday life. Discussions have begun on how to add actual ontology into the Semantic Web. Traditionally part of the major branch of philosophy known as metaphysics, ontology deals with questions concerning what entities exist or can be said to exist, and how such entities can be grouped, related within a hierarchy, and subdivided according to similarities and differences. In other words, it defines how each piece of data is managed and sorted in relation to what you are looking for via categorization. Soon, developers will change the way their databases are structured and use a Semantic Web application to assist with a search that pertains to the categorized way we search for something on the web. Databases in Semantic Web will all be relational and no longer be flat files stored within a database table. As of now, a computer cannot tell what you are looking for. As the abundance of information grows ten fold on the internet, we will require a better method of sorting material via classification types. Since your machine cannot tell you what you are looking for, it cannot relate exactly so we will require data to describe data and various levels of data to be categorized in multiple levels to achieve a better user experience. This is the precipice of the Semantic Web.

Semantic Web requires adding semantic metadata, or data that describes data, to information resources. This will allow machines to effectively process the data based on the semantic information that describes it. When there is enough semantic information associated with data, computers will be able make inferences about the data, i.e., understand what a data resource is and how it relates to other data.

XML (eXtensible Markup Language) has paved the way by adding some metadata in the form of human-readable tags that describe data. In addition, XML documents can include information about the author of a Web page, relevant keywords for search engine optimization, and the software tools used to create the XML file. XML will most likely play a huge role in the integration of the new web.

The other technology expected be a strong part of the Semantic Web is Resource Description Framework (RDF). This will be the tagging association to various topics. Soon we will be able to input actual questions to obtain specific answers. RDF does exactly what its name indicates -- using XML tags, it provides a framework to describe resources. In RDF terms, everything in the world is a resource. This framework pairs the resource (any noun, like "Toyota" or "Celica" ) with a specific item or location on the Web so the computer knows exactly what the resource is.

Let's say you're looking for a Toyota and know you want a pre-owned Celica with a certain amount of mileage on it from a dealership within 20 miles of your house. In the world of the Semantic Web, you won't need to browse a million sites to find what you want because all of the dealer sites that have "used" Celicas for sale with less than "X" amount of mileage within a certain geographic location will be displayed. That's because a Semantic Web search makes matches based on specific tagged relationships.

A simple relational semantic diagram explains a little about Semantic Web's hierarchy.

With the Semantic Web, you have other options. You could enter your preferences into a computerized agent, which would search the web, find YOUR best options, and even place your order or supply contact information. The agent program could then open personal finance software on your computer and record all of the pertinent information about you and your order and mark what your specific habits and preferences to use in the future. For instance, if you had a bad experience or another web site does not contain elements that suit your natural habits it may alert or direct you to another site more suitable for your personal matched criteria.

This gives the web a life of its own that we never would have expected from Artificial Intelligence. Of course it is NOT AI at all, simply the power to mimic it so people can find people or things they relate to. That's what Semantic Web is all about, people, not machines.

But of course we still have to look behind the scenes to see how this works.

Even with the framework that XML and RDF provide, a computer still needs a very direct, specific way of understanding who or what these resources are. To do this, RDF uses uniform resource identifiers (URIs) to direct the computer to a document or object that represents the resource. You're already familiar with the most common form of URI -- the uniform resource locator (URL), which begins with http://. A URI can point to anything on the Web and may also point to objects that are not part of the web, like appliances in computerized homes. Mailto, ftp and telnet addresses are some other examples of URIs.

Semantic Web will be an exciting new way to approach the World Wide Web and will assist us in managing the vast amount of data that now exists. The trouble with ontologies is that they are very difficult to create, implement and maintain. Depending on their scope, they can be enormous, defining a wide range of concepts and relationships.

Contact Leif at lfifer@praxisagency.com.