Slight addition to this, The scheme not only disambiguates the term, it also identifies the means of interpreting the term. For instance, Tim Bray's feed uses a scheme/term combo that can be concatenated to form a meaningful, dereferencable URI.
- James Laurent Le Meur wrote: >>> Could an atom 1.0 feed contain some item whith >>> "<category scheme='http://www.tbray.org/ongoing/tag/' term='Java' >>> somexmlns:href='http://www.tbray.org/ongoing/What/Technology/Coding/Java/' >> /> >>> and other item with >>> "<category scheme='http://www.tbray.org/ongoing/tag/' term='Java' >>> somexmlns:href='http://www.tbray.org/ongoing/What/Technology/Sun/Java/' /> >>> where the first Java is not the same as the second ? >> The term is machine readable. The label is human readable. >> >> <category >> scheme='http://www.example.org/cat/' >> term='http://www.example.org/cat/Technology/Coding/Java/' >> label='Java' >> /> >> <category >> scheme='http://www.exmple.org/' >> term='http://www.example.org/cat/Technology/Sun/Java/' >> label='Java' >> /> >> >> Regards, >> Aristotle Pagaltzis // <http://plasmasturm.org/> > > Aristotle, > > I agree with your statement but feel your example somewhat misleading. From my > understanding: > > - A 'term' is a token (syntactically a string) used for indexing; in the > absence > of an associated scheme it is processed as a free keyword/tag. There's no real > reason to make it a URI, but it can be a number (eg ISBN code). > > - A 'scheme' is the identifier of a controlled vocabulary = a set of terms. > It's > an IRI. It is optional, but 'scopes' the term, so ambiguities are avoided. If > present {scheme,term} is a tuple that unambiguously identifies a resource. > {http://www.software.org/, java} and { http://www.island.org/ , java} are > clearly different categories. > > A note regarding the {scheme, code} tuple: the spec does not indicate how more > information about the category can be found, using some form of concatenation > of > the scheme URI + term. > > - A 'label' is a human readable string associated with a category code (term). > > A note regarding 'label':= limitations of the spec are: > - it is not possible to represent several labels in different languages > - it is not possible to apply i18n attributes like 'dir' to a label. > > Best regards > Laurent Le Meur > AFP > > > > -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- > > This e-mail, and any file transmitted with it, is confidential and intended > solely for the use of the individual or entity to whom it is addressed. If > you have received this email in error, please contact the sender and delete > the email from your system. If you are not the named addressee you should > not disseminate, distribute or copy this email. > > For more information on Agence France-Presse, please visit our web site at > http://www.afp.com > > -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- > >
