XML-based specifications for the news industry fall into four broad categories (most specifications try to cover more than one of the categories, with mixed success):
The following feature matrix shows the coverage for each specification:
|Text Content||NITF, XMLNews.|
|Metadata||NewsML, NITF, PRISM, RSS, XMLNews.|
Information and Content Exchange. ICE is a full-featured content syndication protocol, supporting both push and pull distribution models.
A packaging and metadata format for news objects. NewsML provides sophisticated support for compound news objects consisting of different media, possibly with the same objects available in multiple formats. While NewsML is not intended directly as a syndication format, it supports both inline and out-of-line news objects, and thus is compatible with both push and pull news distribution models.
News Industry Text Format. An HTML-derived format for encoding textual news stories. Includes limited support for metadata, but allows precise inline placement of some metadata information.
Publishing Requirements for Industry Standard Metadata. Like RSS and XMLNews-Meta, PRISM provides full metadata support through RDF. Packaging support is limited, and is based on Multipart-MIME rather than an XML format.
Known both as Rich Site Summary and RDF Site Summary. RSS 0.91 is a wildly popular Web format for syndicating headlines on the Web, and RSS 1.0 is a new proposal for full metadata support through RDF, as with PRISM and XMLNews-Meta. RSS 0.91 has severly limited metadata support (fixed in 1.0), and both allow syndication by pull only.
A pair of specifications, XMLNews-Meta for metadata, and XMLNews-Story for textual news content. Like PRISM and RSS, XMLNews-Meta is based on RDF, and XMLNews-Story is a subset of an early version of NITF.