In the first of an infrequent set of weblog entries I’ll be briefly exploring the RSS 1.0 modules. The first on the list is the Taxonomy module. The taxonomy module is a way of specifying topical structure within an RSS channel.
The Taxonomy modules has a namespace is referenced by including the following namespace in your RSS document.
xmlns:taxo = "http://purl.org/rss/1.0/modules/taxonomy/"
The modules contains two elements the “topic” and “topics” elements. Use of these elements, and the taxonomy namespace, is not very widespread at present (Syndic8 stats). The taxonomy module has many potential uses however. For example filtering an RSS channel by topic could be an interesting development for a large feeds. Other aggregation strategies could be based upon gathering items from a variety of channels with a commonly identified topic, this kind of meta information is potentially more useful than simple textual analysis to discover similarities, and may enable knowledge discovery even when synonyms to common terms are used. See the taxonomy module details for more information on how to integrate this module with an RSS 1.0 feed.