The pace of change in the world is unquestionably accelerating and perhaps nowhere is this more evident than the web. In the past few years online services like flickr, Wikipedia and MySpace have opened our eyes to the unrealized potential of the web and ushered in a new era of web applications that have become the hallmark of Web 2.0. Although some of these services have been around for a few years it’s only been the past year or two that the term Web 2.0 has really become mainstream. Prior to this, the term Web 2.0 was really only tossed around by uber geeks working on the bleeding edge of web development. Now we’re talking about Web 3.0, the Semantic Web. Although the term Web 3.0 is fairly new, the Semantic Web is certainly not.
In 1999 Tim Burners-Lee, the inventor of the world wide web, described his vision of the web
"I have a dream for the Web [in which computers] become capable of analyzing all the data on the Web – the content, links, and transactions between people and computers. A ‘Semantic Web’, which should make this possible, has yet to emerge, but when it does, the day-to-day mechanisms of trade, bureaucracy and our daily lives will be handled by machines talking to machines. The ‘intelligent agents’ people have touted for ages will finally materialize."
And in a 2001 Scientific American article he suggested that a revolution was coming that would evolve the current web into this new ‘Semantic Web’. Well it’s 2007 and I think it’s safe to say Tim Berners-Lee’s vision is still just a vision. Don’t get me wrong, there’s been huge steps forward in terms of tools and technology, as you’ll see with the links provided at the end of this post, but there’s more to it than just tools and technology. So what happened? Why is this evolution of the web that Tim Berners-Lee talked about in 2001, the Semantic Web, now being referred to as Web 3.0, taking so long to get rolling? After all, six years is a lifetime when it comes to the web. To answer that question it’s helpful to step back a few versions to Web 1.0.
In the beginning there was the web, now referred to as Web 1.0. With Web 1.0 website content is provided by content developers, typically the website owner or creator. Anyone who has built a website knows that content creation can be a very time consuming, and therefore expensive, endeavor. As a result the content is fairly static, and when it does change it’s usually at the discretion of the website owner. As users of the web, content consumers, we’re at the mercy of the content creators. The creators decide what is “available” to us and as consumers we decide what to view. Much like the magazine industry, there is a clear separation between content creators and content consumers.
One of the shortcomings with all this content is that it was created for human consumption. Tim Berners-Lee understood this shortcoming in 1999 when he expressed his vision of the Semantic Web. Making content consumable for humans means making content understandable by humans. Making content consumable by computers means making content understandable by computers. Why would we want to do this? If the content is understandable by computers we can create much more sophisticated and useful software that’s capable of doing much more for us, essentially becoming an agent at our beck and call. An example from the now famous 2001 Scientific American article by Tim Berners-Lee may help to understand this potential:
"His sister, Lucy, was on the line from the doctor’s office: "Mom needs to see a specialist and then has to have a series of physical therapy sessions. Biweekly or something. I’m going to have my agent set up the appointments." Pete immediately agreed to share the chauffeuring.
At the doctor’s office, Lucy instructed her Semantic Web agent through her handheld Web browser. The agent promptly retrieved information about Mom’s prescribed treatment from the doctor’s agent, looked up several lists of providers, and checked for the ones in-plan for Mom’s insurance within a 20-mile radius of her home and with a rating of excellent or very good on trusted rating services. It then began trying to find a match between available appointment times (supplied by the agents of individual providers through their Web sites) and Pete’s and Lucy’s busy schedules. (The emphasized keywords indicate terms whose semantics, or meaning, were defined for the agent through the Semantic Web.)"
One way of making the above example possible is to make the content more meaningful by adding semantics to the content. This way the software that’s doing the work for us, the Semantic Web agent, doesn’t necessarily need to be super smart since the meaning of the content isn’t so much derived by the software agent, but rather by the content creator when they included semantics in the content during creation. The intelligence behind the Semantic Web isn’t supplied primarily by the software, but rather by the person creating the content.
Making applications work together by sharing information in a meaningful way, as described in the above example, requires creating a formal specification of the important terms in the content and the relationships between them. This formal specification is usually specific to a domain of knowledge such as, for example, business directories, medicine, movies or food, and is often referred to as an ontology. Creating these ontologies for the various domains of knowledge, of which are almost uncountable in number, requires not only an agreed upon language to describe them, but also an incredible amount of effort on the part of the content creators. Imagine the effort required to supplement all of the information on the web with ontologies in order to allow applications to work together and share information as described in the vision of the Semantic Web. This is in fact one of the key problems cited by detractors of the Semantic Web and one of the key reasons why the Semantic Web has been a long time in the making.
Although the Semantic Web has not materialized as Tim Berners-Lee envisioned it, development of the tools and technologies behind the idea have certainly progressed (see references at end of article for more on the current state of these technologies). But even as these tools and technologies have progressed, the realization of the Semantic Web still requires an enormous effort on the part of content creators.
Enter Web 2.0 and the producer-consumer, or prosumer. The massive collaboration involved in Web 2.0 style applications has empowered the consumer to also become a producer. In fact, it’s the act of content consumer turning content producer that’s largely responsible for the meteoric rise of flickr, Wikipedia, MySpace and the latest golden child FaceBook. Web 2.0 was built on the realization that if you give people the right tools they will happily create content and therefore lift the burden of content creation from the website owner. It seems obvious in hindsight, but it wasn’t so obvious just a few years ago. After all, are most consumers capable of creating content worth viewing? When there’s little at stake, such as in the case of a large percentage of content produced on social networks like MySpace and FaceBook, won’t most of the content be useless and simply create more garbage to sort through while trying to find useful information on the web? The incredible growth of sites like FaceBook show this apparently isn’t the case. It turns out that even The Dullest Blog in the World is meaningful to somebody, even if only for a laugh.
It would be wrong to think of Web 2.0 as simply mass collaboration driven content. As Don Tapscott describes in his book “Wikinomics: how mass collaboration changes everything”, peer based mass collaboration not only creates content but incredible value and is reshaping the global economic landscape. Wikipedia, with its more than 75,000 active unpaid contributors working on more than 5.8 million articles, now dwarfs both the hard copy and the online version of Encyclopedia Britannica. Do you think Encyclopedia Britannica is scared? You bet they are. As the world continues to move from an industrial based economy to a knowledge based economy no industry, sector or business will be immune from its effects. Some have speculated that even the web giant Google may be under pressure from this economic shift which brings us back to Web 3.0.
With content consumers becoming content producers we now have the massive workforce required to create the ontologies needed to make the Semantic Web a reality. Take Wikipedia’s 75,000 volunteer contributors and suddenly creating all those ontologies seems a little less daunting. Sure, creating an ontology for a domain of knowledge requires more knowledge than simply the domain knowledge itself, you have to understand ontologies and how to create them as well. Fortunately the development of specialized ontology languages like the OWL Web Ontology Language and the numerous semantic web tools that have been developed are helping to alleviate this problem and bring ontology creation to the masses.
So it seems that the open, mass collaboration movement on the web, now referred to as Web 2.0, is giving new life the possibility of a Semantic Web. Some people may think it’s hype, fad or just the beginning of the next bubble, but many think otherwise, like Google and Wikipedia who are racing to build next generation Semantic Search engines. Some have even speculated that the Semantic Web could be the undoing of Google as speculated in the famous Evolving Trends blog post “Wikipedia 3.0: The End of Google”.
For an excellent example of how the Semantic Web is being used today check out ontoworld.org, a wiki about the Semantic Web, built on the Semantic Media Wiki open source project.
Additional Resources
Books
Wikinomics: how mass collaboration changes everything by Don Tapscott and Anthony D. Williams
This book is a decent introduction to the impact of mass collaboration. It’s a fairly quick read with plenty of examples of how Web 2.0 is impacting not just the traditional online business, but the global economy as a whole. There are numerous examples of how the brick and morters are taking advantage of this shift from consumer to producer.
The Wealth of Networks: How Social Production Transforms Markets and Freedom by Yochai Benkler
The Wealth of Networks is far more in depth than Wikinomics and a much more academic in nature. By academic I’m not implying impractical, far from it, in fact this book will give you and excellent in depth understanding of what’s behind social production and the implications for the world ahead.
Online Resources
The Semantic Web: A new form of Web content that is meaningful to computers will unleash a revolution of new possibilities – The seminal 2001 Scientific American article by Tim Berners-Lee, James Hendler and Ora Lassila
Wikipedia 3.0: The End of Google? – Famous thought provoking article speculating on some of the implications of the Semantic Web for Google and Wikipedia.
Google Co-Op: The End of Wikipedia? – perhaps Google’s attempt to deal with the Wikipedia threat?
OWL Web Ontology Language
W3C Semantic Web FAQ
ontoworld.org – An excellent resource for the Semantic Web. Basically a wiki about the Semantic Web, built on the Semantic Media Wiki. The Semantic Web in action.
Sweet Tools – a huge list of Semantic Web related tools
