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Re: Comments to Semantic Web FAQ [1/2]

From: Ivan Herman <ivan@w3.org>
Date: Tue, 17 Apr 2007 12:23:20 +0200
Message-ID: <4624A018.9050006@w3.org>
To: uldis.bojars@deri.org
CC: 'Sandro Hawke' <sandro@w3.org>, public-sweo-ig@w3.org
Just to record here...

- for the 'What is RDF' question, I would prefer to keep to the current
text. 'for data interchange on the Web'. I take Uldis' point that we
have to differentiate it from XML, but we do not want to invalidate XML
in this respect (that is also a W3C technology!:-) either. However, I
think if one looks at the whole answer and not that sentence only, the
difference becomes clearer. In any case, I have not found any other
terms ('the describing data on the Web' has already created LOTS of
misunderstandings in terms of metadata, so that terminology is indeed to
be avoided, I agree with Sandro.

- I have also changed for Sandro's text on the URI stuff although I
shortened it a little bit.


Uldis Bojars wrote:
> Thanks to Sandro for comments.
>>>> 4.1. What is RDF?
>>> -> "for describing
>>> data on the Web".
>>> "data interchange" 
>> I disagree.   RDF is for exchanging data, not just metadata.
>> That should probably be a FAQ.   (I thought there was at least something
>> about it on the mythbusting page, but I can't find it now.)   
> Absolutely - RDF is about data. 100% agree.
> Note: it does not say "for describing data about data", no suggestion about
> metadata at all.
> What I want to do with this change is to differentiate RDF from XML. If we
> use the same explanation as XML has been using for a long time now - "data
> interchange on the Web" - then it makes one think: "wait, isn't this what
> XML is for already?". While "data interchange" is technically correct it may
> help if we find a different wording, different from XML.
> That's why I suggest "for describing data" [or "describing knowledge /
> information on the Web"]. 
> It means more than just data interchange to me as RDF is used to describe
> the world, things in it (resources) and relations between them.
> You may find a better wording for what I wanted to express here.
> Note: there is another problem with the formulation "for data interchange on
> the Web". RDF can be used to describe and interchange data in corporate
> environment which technically is not "the Web". 
>>>> 4.3. Where is the "Web" in the Semantic Web?
>>> "URI-s are used to to name resources in RDF triples" -> "URI-s are 
>>> used to name and uniquely identify resources in RDF triples"
>> While I think the term "uniquely identify" is technically correct, it's a
> bit of a problem because it suggests to some people that each resource has
> only one name (a unique identifier), which is not the case.
> "Uniquely identified" helps to better understand how statements merge
> together and form graphs. 
> We will need to introduce it somewhere and I tried to do that carefully.
> Note that the saying "named" can lead to the very same understanding in some
> people - that there is only one name.
> In fact, technically they will be correct. Every resource in RDF has only
> one URI. If two resources have the same URI they are the same, and if they
> have different URIs they are different resources. (Unless I am mistaken).
> This concept is important enough to use "uniquely identified" in the FAQ
> (without going into details described here). 
> It is only when we get to ontology languages like OWL that we can say that
> two different URIs are actually the same.
>>   - in 4.3 Where is the "Web" in Semantic Web?
>>    Here's a rewrite in that direction.  Maybe it goes too far, but
>>    hopefully it makes my point clear:
> It's a nice answer which explains URIs in enough detail. 
> No need for "uniquely identified" here any more but it may make sense to
> mention it at least once elsewhere in this FAQ (when talking about naming
> resources).
> The sentence talking about globally-shared meaning for URIs may be too much
> detail for this question though. 
> Uldis
> [ http://captsolo.net/info/ ]


Ivan Herman, W3C Semantic Web Activity Lead
URL: http://www.w3.org/People/Ivan/
PGP Key: http://www.cwi.nl/%7Eivan/AboutMe/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf

Received on Tuesday, 17 April 2007 11:56:19 UTC

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