Timbl's Blog - Details

Well, the Semantic Web has been in the news a bit recently.

There was thebuzzabout Twine, a"Semantic Web company", getting another round of funding. Then, Yahooannouncedthat it will pick up Semantic Web information from the Web, and use it to enhance search. And now the Times online mis-states that I think"Google could be superseded". Sigh. In an otherwise useful discussion largely about what the Semantic Web is and how it will affect people, a misunderstanding which ended up being the title of the blog. In fact, the conversation as I recall started with a question whether, if search engines were thekiller appfor the familiar Web of documents, what will be thekiller appfor the Semantic Web.

Text search engines are of course good for searching the text in documents, but the Semantic Web isn't text documents, it is data. It isn't obvious what the killer apps will be - there are many contenders. We know that the sort of query you do on data is different: theSPARQL standarddefines a query protocol which allows application builders to query remote data stores. So that is one sort of query on data which is different from text search.

One thing to always remember is that the Web of the future will have BOTH documents and data. The Semantic Web will not supersede the current Web. They will coexist. The techniques for searching and surfing the different aspects will be different but will connect. Text search engines don't have to go out of fashion.

The"Google will be superseded" headline is an unfortunate misunderstanding. I didn't say it. (We have, by the way, asked it to be fixed. One can, after all, update a blog to fix errors, and this should be appropriate. Ian Jacobs wrote an email, left voice mail, and tried to post a reply to the blog, but the reply did not appear on the blog - moderated out? So we tried.)

Now of course, as the name of The Times was once associated with a creditable and independent newspaper :-), the headline was picked up and elaborated on by various well-meaning bloggers. So the blogosphere, which one might hope to be the great safety net under the conventional press, in this case just amplified the error.

I note that here the blogosphere was misled by an online version of a conventional organ. There are many who worry about the inverse, that decent material from established sources will be drowned beneath a tide of low-quality information from less creditable sources.

TheMedia Standards Trustis a group which has been working with theWeb Science Research Initiative(I'm a director of WSRI) to develop ways of encoding the standards of reporting a piece of information purports to meet:"This is an eye-witness report"; or"This photo has not been massaged apart from: cropping"; or"The author of the report has no commercial connection with any products described"; and so on. Likecreative commons, which lets you mark your work with a licence, the project involves representing social dimensions of information. And it is another Semantic Web application.

In all this Semantic Web news, though, the proof of the pudding is in the eating. The benefit of the Semantic Web is that data may bere-usedin ways unexpected by the original publisher. That is the value added. So when a Semantic Web start-up either feeds data to others who reuse it in interesting ways, or itself uses data produced by others, then we start to see the value of each bit increased through thenetwork effect.

So if you are a VC funder or a journalist and some project is being sold to you as a Semantic Web project, ask how it gets extra re-use of data, by people who would not normally have access to it, or in ways for which it was not originally designed. Does it use standards? Is it available in RDF? Is there a SPARQL server?

A great example of Semantic Web data which works this way is Linked Data. There is growing mass of interlinked public data much of it promoted by theLinked Open Dataproject. There is an upcomingLinked Data workshopon this at the WWW 2008 Conference in April in Beijing, and in June 17-18 in New York at theLinked Data Planet Conference. Linked data comes alive when you explore it with a generic data browser like theTabulator. It also comes alive when you make mashups out of it. (SeePlaying with Linked Data, Jamendo, Geonames, Slashfacet and Songbird;Using Wikipedia as a database). It should be easier to make those mashups by just pulling RDF (maybe using RDFa or GRDDL) or using SPARQL, rather than having to learn a new set of APIs for each site and each application area.

I think there is an important"double bus" architecturehere, in which there are separate markets for the raw data and for the mashed up data. Data publishers (e.g., government departments) just produceraw data now, and consumer-facing sites (e.g., soccer sites) mash up data from many sources. I might talk about this a bit atWWW 2008.

So in scanning new Semantic Web news, I'll be looking out for re-use of data. The momentum around Linked Open Data is great and exciting -- let us also make sure we make good use of the data.

Well, it has been a long time since my last post here. So many topics, so little time. Some talks, a couple of Design Issues articles, but no blog posts. To dissipate the worry of expectation of quality, I resolve to lower the bar. More about what I had for breakfast.

So TheGraphword has been creeping in. BradFitz talks of theSocial Graphas does Alex Iskold, whodiscussessocial graphs and network theory in general, points out that users want to own their own social graphs. He alo points out that examples of graphs are the Internet and the Web. So what's with theGraphword?

Maybe it is becauseNet andWebhave been used. For perfectly good things .. but different things.

TheNetwe normally use as short for Internet, which is the International Information Infrastructure. Al Gorepromotedthe National Information Infrastructure (NII) presumably as a political pragma at the time, but clearly it became International. So let's call it III. Let's think about the Net now as an invention which made life simpler and more powerful. It made it simpler because of having to navigate phone lines from one computer to the next,you could write programs as though the net were just one big cloud, where messages went in at your computer and came out at the destination one. The realization was,"It isn't the cables, it is the computers which are interesting". The Net was designed to allow the computers to be seen without having
to see the cables.

Simpler, more powerful. Obvious, really.

Programmers could write at a more abstract level. Also, there was re-use of the connections, in that, as the packets flowed, a cable which may have been laid for one purpose now got co-opted for all kinds of uses which the original users didn't dream of. And users of the Net, the III, found that they could connect to all kinds of computers which had been hooked up for various reasons, sometimes now forgotten. So the new abstraction gave us more power, and added value by enabling re-use.

The wordWebwe normally use as short for World Wide Web. The WWW increases the power we have as users again. The realization was"It isn't the computers, but the documents which are interesting". Now you could browse around a sea of documents without having to worry about which computer they were stored on. Simpler, more powerful. Obvious, really.

Also, it allowed unexpected re-use. People would put a document on the web for one reason, but it would end up being found by people using it in completely different ways. Two delights drove the Web: one of being told by a stranger your Web page has saved their day, and the other of discovering just the information you need and for which you couldn't imagine someone having actually had the motivation to provide it.

So the Net and the Web may both be shaped as something mathematicians call a Graph, but they are at different levels. The Net links computers, the Web links documents.

Now, people are making another mental move. There is realization now,"It's not the documents, it is the things they are about which are important". Obvious, really.

Biologists are interested in proteins, drugs, genes. Businesspeople are interested in customers, products, sales. We are all interested in friends, family, colleagues, and acquaintances. There is a lot of blogging about the strain, and total frustration that, while you have a set of friends, the Web is providing you with separate documents about your friends. One in facebook, one on linkedin, one in livejournal, one on advogato, and so on. The frustration that, when you join a photo site or a movie site or a travel site, you name it, you have to tell it who your friends are all over again. The separate Web sites, separate documents, are in fact about the same thing -- but the system doesn't know it.

There are cries from the heart (e.gThe Open Social Web Bill of Rights) for my friendship, that relationship to another person, to transcend documents and sites. There is a"Social Network Portability" community. Its not the Social NetworkSitesthat are interesting -- it is the Social Network itself. The Social Graph. The way I am connected, not the way my Web pages are connected.

We can use the wordGraph, now, to distinguish fromWeb.

I called this graph the Semantic Web, but maybe it should have been Giant Global Graph! Any worse than WWWW? ;-)   Not the"Semantic Web" term has been established for a long time, I'm not proposing to change it.  But let's think about the graph which it is.  (Footnote:"Graph" also happens to be the word the RDF specifications use, but that is by the way. While an XML parser creates a DOM tree, an RDF parser creates an RDF graph in memory.)

So, if only we could express these relationships, such as my social graph, in a way that is above the level of documents, then we would get re-use. That's just what the graph does for us. We have the technology -- it is Semantic Web technology, starting with RDF OWL and SPARQL.  Not magic bullets, but the tools which allow us to break free of the document layer. If a social network site uses a common format for expressing that I know Dan Brickley, then any other site or program (when access is allowed) can use that information to give me a better service. Un-manacled to specific documents.

I express my network in a FOAF file, and that is a start of the revolution. I blogged on FOAF filesearlier, before the major open SNS angst started. The data in a FOAF file can be read by other applications. Photo-sharing, travel sites, sites which accept your input because you are a part of the graph.

The less inviting side of sharing is losing some control. Indeed, at each layer --- Net, Web, or Graph --- we have ceded some control for greater benefits.

People running Internet systems had to let their computer be used for forwarding other people's packets, and connecting new applications they had no control over. People making web sites sometimes tried to legally prevent others from linking into the site, as they wanted complete control of the user experience, and they would not link out as they did not want people to escape. Until after a few months they realized how the web works. And the re-use kicked in. And the payoff started blowing people's minds.

Letting your data connect to other people's data is a bit about letting go in that sense. It is stillnotabout giving to people data which they don't have a right to. It is about letting it be connected to data from peer sites. It is about letting it be joined to data from other applications.

It is about getting excited about connections, rather than nervous.


In the short, what-can-I-code-up-this-afternoon-to-fix-this term, it is about other sites following the lead of my.opera.com, livejournal, advogato, and so on (list) also exporting a public RDF URI for their members, with what information the person would like to share.Right now, this blog re-uses the FOAF data linked to us tofight spam.

In the long term vision, thinking in terms of the graph rather than the web is critical to us making best use of the mobile web, the zoo of wildy differing devices which will give us access to the system. Then, when I book a flight it is the flight that interests me. Not the flight page on the travel site, or the flight page on the airline site, but the URI (issued by the airlines) of the flight itself. That's what I will bookmark. And whichever device I use to look up the bookmark, phone or office wall, it will access a situation-appropriate view of an integration of everything I know about that flight from different sources. The task of booking and taking the flight will involve many interactions. And all throughout them, that task and the flight will be primary things in my awareness, the websites involved will be secondary things, and the network and the devices tertiary.

I'll be thinking in the graph. My flights. My friends. Things in my life. My breakfast. What was that? Oh, yogourt, granola, nuts, and fresh fruit, since you ask.

People have, since it started, complained about the fact that there is junk on the web. And as a universal medium, of course, it is important that the web itself doesn't try to decide what is publishable. The way quality works on the web is through links.

It works because reputable writers make links to things they consider reputable sources. So readers, when they find something distasteful or unreliable, don't just hit the back button once, they hit it twice. They remember not to follow links again through the page which took them there. One's chosen starting page, and a nurtured set of bookmarks, are the entrance points, then, to a selected subweb of information which one is generally inclined to trust and find valuable.

A great example of course is the blogging world. Blogs provide a gently evolvingnetwork of pointers of interest. As do FOAF files. I've always thought that FOAF could be extended to provide a trust infrastructure for (e..g.) spam filtering and OpenID-style single sign-on and its good to see things happening in that space.

In a recent interview with the Guardian, alas, my attempt to explain this was turned upside down into a"blogging is one of the biggest perils"message. Sigh. I think they took their lead from an unfortunate BBC article, which for some reason stressed concerns about the web rather than excitement, failure modes rather than opportunities.(This happens, because when you launch aWeb Science Research Initiative, people ask what the opportunities are and what the dangers are for the future. And someeditors are tempted to just edit out the opportunities and headline the fears to get the eyeballs, which is old and boring newspaper practice. We expect better from theGuardianandBBC, generally very reputable sources)

In fact, it is a really positive time for the web. Startups arelaunching, and beingsold[Disclaimer: people I know]again, academics are excited about new systems and ideas, conferences and camps and wikis and chat channels and are hopping with energy, and every morning demands an excruciating choice of which exciting link to follow first.

And, fortunately, we have blogs. We can publish what we actually think, even when misreported.