RSS 1.0 (RDF Site Summary) is a well-known XML format commonly used for syndicating news headlines. By design it is an extensible format in which metadata expressed using any RDF vocabulary can be linked to its component items, while still maintaining compatibility with applications such as newsreaders that may be unaware of such vocabularies. This paper will discuss some interesting applications that can be built with RSS as a base. The annotation of collections of photographs is used as a case study.

Using an RDF representation of Wordnet, the lexical database of English, we attach keywords to photographs to indicate what they objects they depict. With simple inference logic, we create improved search engines over this data. We can automatically build a Yahoo-like hierarchical web site of photographs organised by the meaning of their keywords. Using the Friend Of A Friend (FOAF) vocabulary, we can record which photographs show particular people. Applications can then display related information with the photograph by using information gathered by spidering the existing network of FOAF information on the web.

RDF's natural integration with the web's URI system makes it easy to build applications in a loosely-coupled style. Tools for this project built using Perl and Java easily interoperate, using the RDF output of one as the input of another. New applications can be built by others using any language or environment with RDF and HTTP support (even Mozilla), without needing to be granted any special database access or other privileges.