WWW FAQs: What is RSS?

2004-09-14: RSS is an HTML-like, XML-compliant format for blogs. RSS is usually said to stand for "Really Simple Syndication." RSS was originally invented by Netscape Communications Corporation as a format for "channels," a feature of the Netscape 3.0 web browser. While channels did not take the world by storm, the format became the basis for a good idea: by publishing an RSS "feed" and giving the world permission to reproduce it, anyone can contribute to a virtual "newswire" service. RSS aggregators can then bring the latest stories from many blogs together in chronological order.

While blogging appears to take control of formatting and presentation away from the author, the reality is that blog entries (or "items") are typically short summaries or "teasers" associated with a link to the author's website or another site relevant to the story in question. In this way, RSS feeds help to bring new readers to many websites.

Despite the fundamental simplicity of the idea, the RSS "industry" is crowded with competing standards and conflicting histories. Important RSS "standards" in use today include:

1. RSS 0.91. The original Netscape channels specification. Generated by blosxom and other tools. Very simple and direct. Entries can contain HTML elements for formatting and additional links.

1. RSS 1.0. Standardized by the RSS-DEV working group. A very complete standard, including namespaces, extension mechanisms, and various things perhaps lacking in RSS 0.91. Despite the name, this is NOT related to RSS 2.0, and indeed it is not a superset of RSS 0.91.

1. RSS 2.0. Published by the Berkman Center at Harvard Law. A much simpler standard completely unrelated to RSS 1.0, RSS 2.0 attempts to maintain the spirit of RSS 0.91 while filling in gaps.

Perhaps at some future date a single RSS standard will emerge as the preferred format. In the meantime, however, the major syndication services accept well-formed and not-so-well-formed blogs in all of the above formats, and more. You may choose any of the above, with good results. I presently use both RSS 0.91, for Innards, and RSS 1.0, for the RSS feed of the WWW FAQ.

For a particularly thorough effort to make sense of the history of RSS, see Ronan Waide's RSS presentation notes.

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