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476 lines
23 KiB
476 lines
23 KiB
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<TITLE>Realising the Full Potential of the Web</TITLE>
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<H1 ALIGN="CENTER">
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Realising the Full Potential of the Web
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</H1>
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Tim Berners-Lee, Director of the World-Wide Web Consortium
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Based on a talk presented at the W3C meeting, London, 1997/12/3
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<H3>
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Abstract
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<FONT FACE="Garamond"></FONT>
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The first phase of the Web is human communication though shared knowledge.
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We have a lot of work to do before we have an intuitive space in which we
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can put down our thoughts and build our understanding of what we want to
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do and how and why we will do it. The second side to the Web, yet to emerge,
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is that of machine-understandable information. As this happens, the day-to-day
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mechanisms of trade and bureaucracy will be handled by agents, leaving humans
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to provide the inspiration and the intuition. This will come about though
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the implementation of a series of projects addressing data formats and languages
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for the Web, and digital signatures.
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<P>
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<H3>
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The original dream
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</H3>
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The Web was designed to be a universal space of information, so when you
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make a bookmark or a hypertext link, you should be able to make that link
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to absolutely any piece of information that can be accessed using networks.
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The universality is essential to the Web: it looses its power if there are
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certain types of things to which you can’t link.
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<P>
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There are a lot of sides to that universality. You should be able to make
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links to a hastily jotted crazy idea and to link to a beautifully produced
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work of art. You should be able to link to a very personal page and to something
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available to the whole planet. There will be information on the Web which
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has a clearly defined meaning and can be analysed and traced by computer
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programs; there will be information, such as poetry and art, which requires
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the full human intellect for an understanding which will always be subjective.
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<P>
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And what was the purpose of all this? The first goal was to work together
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better. While the use of the Web across all scales is essential to the concept,
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the original driving force was collaboration at home and at work. The idea
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was, that by building together a hypertext Web, a group of whatever size
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would force itself to use a common vocabulary, to overcome its misunderstandings,
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and at any time to have a running model - in the Web - of their plans and
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reasons.
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<P>
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For me, the forerunner to the Web was a program called ‘Enquire’,
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which I made for my own purposes. I wrote it in 1980, when I was working
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at the European Particle Physics Lab (CERN), to keep track of the complex
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web of relationships between people, programs, machines and ideas. In 1989,
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when I proposed the Web, it was as an extension of that personal tool to
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a common information space.
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<P>
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When we make decisions in meetings, how often are the reasons for those decisions
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(which we so carefully elaborated in the meeting) then just typed up, filed
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as minutes and essentially lost? How often do we pay for this, in time spent
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passing on half-understandings verbally, duplicating effort through ignorance
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and reversing good decisions from misunderstanding? How much lack of co-operation
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can be traced to an inability to understand where another party is ‘coming
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from’? The Web was designed as an instrument to prevent misunderstandings.
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<P>
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For this to work, it had to be not only easy to ‘browse’, but also
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easy to express oneself. In a world of people and information, the people
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and information should be in some kind of equilibrium. Anything in the Web
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can be quickly learned by a person and any knowledge you see as being missing
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from the Web can be quickly added. The Web should be a medium for the
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communication between people: communication through shared knowledge. For
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this to work, the computers, networks, operating systems and commands have
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to become invisible, and leave us with an intuitive interface as directly
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as possible to the information.
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<H3>
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Re-enter machines
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</H3>
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<FONT FACE="Garamond"></FONT>
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There was a second goal for the Web, which is dependent on the first. The
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second part of the dream was that, if you can imagine a project (company,
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whatever) which uses the Web in its work, then there will be an map, in
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cyberspace, of all the dependencies and relationships which define how the
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project is going. This raises the exciting possibility of letting programs
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run over this material, and help us analyze and manage what we are doing.
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The computer renters the scene visibly as a software agent, doing anything
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it can to help us deal with the bulk of data, to take over the tedium of
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anything that can be reduced to a rational process, and to manage the scale
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of our human systems.
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<H3>
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Where are we now?<FONT SIZE=2> </FONT>
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</H3>
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<P>
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The Web you see as a glorified television channel today is just one part
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of the plan. Although the Web was driven initially by the group work need,
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it is not surprising that the most rapid growth was in public information.
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Web publishing, when a few write and many read, profited most from the snowball
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effect of exponentially rising numbers of readers and writers. Now, with
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the invention of the term ‘intranet’, Web use is coming back into
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organisations. (In fact, it never left. There have always been since 1991,
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many internal servers, but as they were generally invisible from outside
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the companies’ firewalls they didn't get much press!). However, the
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intuitive editing interfaces which make authoring a natural part of daily
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life are still maturing. I thought that in 12 months we would have generally
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available intuitive hypertext editors. (<I>I have stuck to that and am still
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saying the same thing today!)</I>
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<P>
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It is not just the lack of simple editors that has prevented use of the Web
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as a collaborative medium. For a group of people to use the Web in practice,
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they need reliable access control, so that they know their ideas will only
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be seen by those they trust. They also need access control and archival tools
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that, like browsing, don't require one to get into the details of computer
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operating systems.
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<P>
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There is also a limit to what we can do by ourselves with information, without
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the help of machines. A familiar complaint of the newcomer to the Web, who
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has not learned to follow links only from reliable sources, is the about
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the mass of junk out there. Search engines flounder in the mass of
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undifferentiated documents that range vastly in terms of quality, timeliness
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and relevance. We need information about information, ‘metadata’,
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to help us organise it.
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<P>
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As it turns out, many of these long-term needs will hopefully be met by
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technology, which for one reason or another is being developed by the technical
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community, and agreed upon by groups such as the World-Wide Web Consortium
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(W3C), in response to various medium-term demands.
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H3>
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The World Wide Web Consortium - W3C
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</H3>
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<FONT FACE="Garamond"></FONT>
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<P>
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The Consortium exists as a place for those companies for whom the Web is
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essential to meet and agree on the common underpinnings that will allow everyone
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to go forward. (There are currently over 230 member organisations.)
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<P>
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Whether developing software, hardware, networks, information for sale, or
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using the Web as a crucial part of their business life, these companies are
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driven by current emerging areas such as Web publishing, intranet use, electronic
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commerce, and Web-based education and training. From these fields medium-term
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needs arise and, where appropriate, the Consortium starts an Activity to
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help reach a consensus on computer protocols for that area. Protocols are
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the rules that allow computers to talk together about a given topic. When
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the industry agrees on protocols, then a new application can spread across
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the world, and new programs can all work together as they all speak the same
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language. This is key to the development of the Web.
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H2>
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Where is the Web Going Next?
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</H2>
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<H3>
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Avoiding the World Wide Wait
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</H3>
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<P>
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<FONT FACE="Garamond"></FONT>
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<P>
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You've heard about it, you may have experienced it, but can anything be done
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about it?
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<P>
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One reason for the slow response you may get from a dial-up Internet account
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simply follows from the ‘all you can eat’ pricing policy. The only
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thing which keeps the number of Internet users down is unacceptable response,
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so if we were to suddenly make it faster, there would almost immediately
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be more users until it was slow again. I've seen it: when we speeded up an
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overloaded server by a factor of five, it once again rose to 100% utilisation
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as the number of users increased by a factor of five.
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<P>
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Eventually, there will be different ways of paying for different levels of
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quality. But today there some things we can do to make better use of the
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bandwidth we have, such as using compression and enabling many overlapping
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asynchronous requests. There is also the ability to guess ahead and push
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out what a user may want next, so that the user does not have to request
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and then wait. Taken to one extreme, this becomes subscription-based
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distribution, which works more like email or newsgroups.
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<P>
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One crazy thing is that the user has to decide whether to use mailing lists,
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newsgroups, or the Web to publish something. The best choice depends on the
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demand and the readership pattern. A mistake can be costly. Today, it is
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not always easy for a person to anticipate the demand for a page. For example,
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the pictures of the Schoemaker-Levy comet hitting Jupiter taken on a mountain
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top and just put on the nearest Mac server or the decision Judge Zobel put
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onto the Web - both these generated so much demand that their servers were
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swamped, and in fact, these items would have been better delivered as messages
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via newsgroups. It would be better if the ‘system’, the collaborating
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servers and clients together, could adapt to differing demands, and use
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pre-emptive or reactive retrieval as necessary.
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H3>
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Data about Data - Metadata
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</H3>
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<P>
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<FONT FACE="Garamond"></FONT>
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<P>
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It is clear that there should be a common format for expressing information
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about information (called metadata), for a dozen or so fields that needed
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it, including privacy information, endorsement labels, library catalogues,
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tools for structuring and organising Web data, distribution terms and annotation.
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The Consortium's Resource Description Framework (RDF) is designed to allow
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data from all these fields to be written in the same form, and therefore
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carried together and mixed.
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<P>
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That by itself will be quite exciting. Proxy caches, which make the Web more
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efficient, will be able to check that they are really acting in accordance
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with the publisher's wishes when it comes to redistributing material. A browser
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will be able to get an assurance, before imparting personal information in
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a Web form, on how that information will be used. People will be able, if
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the technology is matched by suitable tools, to endorse Web pages that they
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perceive to be of value. Search engines will be able to take such endorsements
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into account and give results that are perceived to be of much higher quality.
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So a common format for information about information will make the Web a
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whole lot better.
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H3>
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The Web of trust
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</H3>
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<P>
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<FONT FACE="Garamond"></FONT>
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<P>
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In cases in which a high level of trust is needed for metadata, digitally
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signed metadata will allow the Web to include a ‘Web of trust’.
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The Web of trust will be a set of documents on the Web that are digitally
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signed with certain keys, and contain statements about those keys and about
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other documents. Like the Web itself, the Web of trust does not need to have
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a specific structure like a tree or a matrix. Statements of trust can be
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added exactly so as to reflect actual trust. People learn to trust through
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experience and though recommendation. We change our minds about who we trust
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for different purposes. The Web of trust must allow us to express this.
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<P>
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Hypertext was suitable for a global information system because it has this
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same flexibility: the power to represent any structure of the real world
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or a created imagined one. Systems that force you to express information
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in trees or matrices are fine so long as they are used for describing trees
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or matrices. The moment you try to use one to hold information that does
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not fit the mold, you end up twisting the information to fit, and so
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misrepresenting the situation. Similarly, the W3C's role in creating the
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Web of trust will be to help the community have common language for expressing
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trust. <I>The Consortium will not seek a central or controlling role in the
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content of the Web.</I>
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H3>
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‘Oh, yeah?’
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</H3>
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<P>
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<FONT FACE="Garamond"></FONT>
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<P>
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So, signed metadata is the next step. When we have this, we will be able
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to ask the computer not just for information, but why we should believe it.
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Imagine an ‘Oh, yeah?’ button on your browser. There you are looking
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at a fantastic deal that can be yours just for the entry of a credit card
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number and the click of a button. "Oh, yeah?", you think. You press the
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‘Oh, yeah?’ button. You are asking your browser why you should
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believe it. It, in turn, can challenge the server to provide some credentials:
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perhaps, a signature for the document or a list of documents that expresses
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what that key is good for. Those documents will be signed. Your browser rummages
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through with the server, looking for a way to convince you that the page
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is trustworthy for a purchase. Maybe it will come up with an endorsement
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from a magazine, which in turn has been endorsed by a friend. Maybe it will
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come up with an endorsement by the seller's bank, which has in turn an
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endorsement from your bank. Maybe it won't find any reason for you to actually
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believe what you are reading at all.
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H3>
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Data about things
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</H3>
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<P>
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<FONT FACE="Garamond"></FONT>
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<P>
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All the information mentioned above is information about information. Perhaps
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the most important aspect of it is that it is machine-understandable data,
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and it may introduce a new phase of the Web in which much more data in general
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can be handled by computer programs in a meaningful way. All these ideas
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are just as relevant to information about the real world: about cars and
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people and stocks and shares and flights and food and rivers.
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<P>
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The Enquire program assumed that every page was about something. When you
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created a new page it made you say what sort of thing it was: a person, a
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piece of machinery, a group, a program, a concept, etc. Not only that, when
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you created a link between two nodes, it would prompt you to fill in the
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relationship between the two things or people. For example, the relationships
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were defined as ‘A is part of B’ or ‘A made B’. The idea
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was that if Enquire were to be used heavily, it could then automatically
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trace the dependencies within an organisation.
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<P>
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Unfortunately this was lost as the Web grew. Although it had relationship
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types in the original specifications, this has not generally become a Web
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of assertions about things or people. Can we still build a Web of well-defined
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information?
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<P>
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My initial attempts to suggest this fell on stony ground, and not surprisingly.
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HTML is a language for communicating a document for human consumption. SGML
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(and now XML) gives structure, but not semantics. Neither the application,
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nor the language, called for it.
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<P>
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With metadata we have a need for a machine-understandable language that has
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all the qualities we need. Technically, the same apparatus we are constructing
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in the Resource Description Framework for describing the properties of documents
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can be used equally well for describing anything else.
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H3>
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A crying need for RDF
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</H3>
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<P>
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<FONT FACE="Garamond"></FONT>
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<P>
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Is there a real need for this metadata and is there a market in the medium
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term that will lead companies to develop in this direction? Well, in the
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medium term, we see the drivers already - web publishing, education and training,
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electronic commerce and intranets.
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<P>
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I have mentioned the vicious circle that caused the Web to take off initially.
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The increasing amount of information on the Web was an incentive for people
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to get browsers, and the increasing number of browsers created more incentive
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for people to put up more Web sites. It had to start somewhere and it was
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bootstrapped by making ‘virtual hypertext’ servers. These servers
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typically had access to large databases - such as phone books, library catalogues
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and existing documentation management systems. They had simple programs which
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would generate Web pages ‘on the fly’ corresponding to various
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views and queries on the database. This has been a very powerful
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‘bootstrap’ as there is now a healthy market for tools to allow
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one to map one's data from its existing database form on to the Web.
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<P>
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Now here is the curious thing. There is so much data available on Web pages,
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that there is a market for tools that ‘reverse engineer’ that process.
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These are tools that read pages, and with a bit of human advice, recreate
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the database object. Even though it takes human effort to analyse the way
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different Web sites are offering their data, it is worth it. It is so powerful
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to have a common, well defined interface to all the data so that you can
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program on top of it. So the need for well defined interface to Web data
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in the short term is undeniable.
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<P>
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What we propose is that, when a program goes out to a server looking for
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data, say a database record, that the same data should be available in RDF,
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in such a way that the rows and columns are all labelled in a well-defined
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way. That it may be possible to look up the equivalence between field names
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at one Web site and at another, and so merge information intelligently from
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many sources. This is a clear need for metadata, just from looking at the
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trouble libraries have had with the numbers of very similar, but slightly
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different ways of making up a catalogue card for a book.
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H3>
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Interactive Creativity
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</H3>
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<P>
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<FONT SIZE=2></FONT>
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<P>
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<P>
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<FONT FACE="Garamond"></FONT>
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<P>
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I want the Web to be much more creative than it is at the moment. I have
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even had to coin a new word - Intercreativity - which means building things
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together on the Web. I found that people thought that the Web already was
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‘interactive’, because you get to click with a mouse and fill in
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forms! I have mentioned that better intuitive interfaces will be needed,
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but I don’t think they will be sufficient without better security.
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<P>
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It would be wrong to assume that digital signature will be mainly important
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for electronic commerce, as if security were only important where money is
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concerned. One of my key themes is the importance of the Web being used on
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all levels from the personal, through groups of all sizes, to the global
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population.
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<P>
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When you are working in a group, you do things you would not do outside the
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group, You share half-baked ideas, reveal sensitive information. You use
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a vernacular that will be understood; you can cut corners in language and
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formality. You do these things because you trust the people in the group,
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and that others won't suddenly have access to it. To date, on the Web, it
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has been difficult to manage such groups or to allow one to control access
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to information in an intuitive way.
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<P>
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<P>
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<B><I><FONT FACE="Arial"></FONT></I></B>
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<H3>
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Letting go
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</H3>
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<P>
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<FONT FACE="Garamond"></FONT>
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<P>
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So, where will this get us? The Web fills with documents, each of which has
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pointers to help a computer understand it and relate it to terms it knows.
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Software agents acting on our behalf can reason about this data. They can
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ask for and validate proofs of the credibility of the data. They can negotiate
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as to who will have what access to what and ensure that our personal wishes
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for privacy level be met.
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<P>
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The world is a world of human beings, as it was before, but the power of
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our actions is again increased. The Web already increases the power of our
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writings, making them accessible to huge numbers of people and allowing us
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to draw on any part of the global information base by a simple hypertext
|
|
link. Now we image the world of people with active machines forming part
|
|
of the infrastructure. We only have to express a request for bids, or make
|
|
a bid, and machines will turn a small profit matching the two. Search engines,
|
|
from looking for pages containing interesting words, will start indexes of
|
|
assertions that might be useful for answering questions or finding
|
|
justifications.
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|
<P>
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|
I think this will take a long time. I say this deliberately, because in the
|
|
past I have underestimated how long something will take to become available
|
|
(e.g. good editors in 12 months).
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|
<P>
|
|
Now we will have to find how best to integrate our warm fuzzy right-brain
|
|
selves into this clearly defined left-brain world. It is easy to know who
|
|
we trust, but it might be difficult to explain that to a computer. After
|
|
seeding the semantic Web with specific applications, we must be sure to
|
|
generalise it cleanly, leaving it clean and simple so that the next generation
|
|
can learn its logical concepts along with the alphabet.
|
|
<P>
|
|
If we can make something decentralised, out of control, and of great simplicity,
|
|
we must be prepared to be astonished at whatever might grow out of that new
|
|
medium.
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|
<H3>
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|
It’s up to us
|
|
</H3>
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|
<P>
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|
<FONT SIZE=2> </FONT>
|
|
<P>
|
|
One thing is certain. The Web will have a profound effect on the markets
|
|
and the cultures around the world: intelligent agents will either stabilise
|
|
or destabilise markets; the demise of distance will either homogenise or
|
|
polarise cultures; the ability to access the Web will be either a great divider
|
|
or a great equaliser; the path will either lead to jealousy and hatred or
|
|
peace and understanding.
|
|
<P>
|
|
The technology we are creating may influence some of these choices, but mostly
|
|
it will leave them to us. It may expose the questions in a starker form than
|
|
before and force us to state clearly where we stand.
|
|
<P>
|
|
We are forming cells within a global brain and we are excited that we might
|
|
start to think collectively. What becomes of us still hangs crucially on
|
|
how we think individually.
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|
<P>
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<HR>
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<P>
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</BODY></HTML>
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