RSS 0.93
- DEPRECATED. A abandoned upgrade of the Userland specification of RSS0.93 - by Dave Winer, April 20 2001
- http://backend.userland.com/rss093

RSS 0.92
- DEPRECATED. The Userland specification of RSS0.92 - by Dave Winer, December 25 2000
- http://backend.userland.com/rss092

RSS 0.91
- DEPRECATED. Description of RSS current practice. By Dave Winer, UserLand.
- http://backend.userland.com/rss091

RSS 2.0 Specification (version 2.0.8)
- The current Really Simple Syndication 2.0 specification, published by the RSS Advisory Board.
- http://www.rssboard.org/rss-specification

rss-dev
- The email list for the RSS interest and working groups, discussing the present and future of the RSS format, as well as working on uses and development. Responsible for RSS1.0
- http://groups.yahoo.com/group/rss-dev/

RSS 1.0: The New Syndication Format
- Background on the RSS 1.0 Spec. By Jonathan Eisenzopf, Web Reference.
- http://www.webreference.com/perl/tutorial/rss1/

Diveintomark - The Myth of RSS Compatibility
- "There are 9 versions of RSS, all of which are incompatible with various other versions." Describes the 9 versions and gives examples of the incompatibility issues.
- http://diveintomark.org/archives/2004/02/04/incompatible-rss

Mod_enclosures Proposal
- Proposal of enclosures support for RSS 1.0 (as module) and RSS 2.0.
- http://www.crocodile.org/lord/RSSenclosures/RSSenclosures.pdf

RSS 1.1
- Draft of RSS 1.1 standard, a proposed replacement to RSS 1.0.
- http://inamidst.com/rss1.1/

RSS 2.0
- The latest "Simple RSS" specification - following on from 0.93, and not including RDF
- http://blogs.law.harvard.edu/tech/rss

RSS 1.0
- The latest "Complex RSS" specification. As created by the members of RSS-DEV. It extends RSS with RDF-style metadata, and modules.
- http://web.resource.org/rss/1.0/

Open Content Syndication Directory Format
- Open Content Syndication is an XML format for describing channel listings, including RSS files.
- http://internetalchemy.org/ocs/directory.html

RSS 0.90
- DEPRECATED: A copy of the original Netscape version of the RSS0.90 specification. This is no longer in use, and is here for historical reasons only.
- http://www.purplepages.ie/RSS/netscape/rss0.90.html