Subject: Question about category@scheme

From: "Byrne Reese" <[email-masked]>
Date: Fri, 7 Oct 2005 13:20:49 -0400

Are there any good examples of how the category@scheme attribute is
used?

4.2.2.2  The "scheme" Attribute
 
   The "scheme" attribute is an IRI that identifies a categorization
   scheme.  Category elements MAY have a "scheme" attribute.

Is it just me, or is that kind of vague?

Or to ask a more leading question, can the scheme element be used to
differentiate between a "category" and a "tag?" And if so, how?

Byrne Reese

Manager, Platform Technology

http://www.sixapart.com/pronet/

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From: James M Snell <[email-masked]>
Date: Fri, 07 Oct 2005 10:44:54 -0700

I don't believe we really have any good best practices for this yet.

My snellspace.com blog uses <category 
scheme="http://www.snellspace.com/wp" term="Atom 1.0" /> to indicate my 
site specific categories

To indicate a tag, one could imagine doing something like:

<category scheme="http://technorati.com/tag/" term="Atom 1.0" />

And include a corresponding link element:

<link rel="related" href="http://technorati.com/tag/Atom+1.0" />

- James

Byrne Reese wrote:

> Are there any good examples of how the category@scheme attribute is used?
>
> differentiate between a “category” and a “tag?” And if so, how?
>
> Byrne Reese
>

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From: Tim Bray <[email-masked]>
Date: Fri, 07 Oct 2005 10:55:04 -0700

> Are there any good examples of how the category@scheme attribute is  
Over at 'ongoing', I have my own set of categories, so my category  
elements look like

<category scheme='http://www.tbray.org/ongoing/What/' term='Business' />

Remember, it's optional, both for the producer and for the consumer  
(Technorati, for example, ignores the scheme); but for well-defined  
taxonomies like Dewey Decimal or whatever, I think it would be a good  
idea to put a URI there to disambiguate them. -Tim

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From: "A. Pagaltzis" <[email-masked]>
Date: Fri, 7 Oct 2005 20:15:39 +0200

* Tim Bray <[email-masked]> [2005-10-07 20:00]:
> Over at 'ongoing', I have my own set of categories, so my
> category  elements look like
> 

Conversely, I generate an Atom feed from my del.icio.us links,
and my category elements look like

    <category scheme="http://del.icio.us/ap/" term="advice" />

So tags vs categories, it doesn’t matter, not to Atom.

Regards,
-- 
Aristotle Pagaltzis // <http://plasmasturm.org/>

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From: "A. Pagaltzis" <[email-masked]>
Date: Fri, 7 Oct 2005 20:17:32 +0200

> differentiate between a "category" and a "tag?" And if so, how?

By using different IRIs for either.

Or if your question is “I don’t want to use a hierarchical filing
system with mutually exclusive choices,” then the answer is,
“Atom doesn’t make you, ‘category’ is to be understood broadly as
any kind of organisational scheme.”

Regards,