Understanding RSS News Feeds

RSS files are one of the most widely used XML formats on the Web. They provide an open format for syndicating all types of content, including podcasts.

RSS files let you create news feeds that can include headlines, links and article summaries from your website content. Because it is a standard format, others can then subscribe to your newsfeed with many popular tools, or incorporate your content into their site.

In addition to syndicating story summaries and headlines, RSS files are now being used to syndicate audio content. This is most commonly called podcasting. In podcasting, RSS files are used to summarize the contents of the audio programs.

What are RSS Files?

The RSS format originated with the sites My Netscape and My UserLand. Dave Winer, an influential developer and early blogger, has shepherded the format through several incarnations. What exactly are these RSS files?

No one agrees to what RSS really stands for. It originally stood for RDF Site Summary. Some call the format Rich Site Summary. With the 2.0 specification, it's called Really Simple Syndication.

According to Dave Winer, author of the current spec, "There is no consensus on what RSS stands for, so it's not an acronym, it's a name. Later versions of this spec may say it's an acronym, and hopefully this won't break too many applications."

RSS files typically contain four types of elements: channel, image, items and text input. Many news feeds use only the channel and item elements.

Here's an example of what a simple RSS file looks like:

<?xml version="1.0"?>
<rss version="2.0">
<channel>
<title>Podcasting Blog</title>
<link>http://www.podcastingnews.com/</link>
<description>Interesting things from Podcasting News</description>
<language>en-us</language>
<copyright>Copyright 2004 Podcasting News</copyright>

<item>
<title>Pioneering Audioblogger</title>
<link>http://www.podcastingnews.com/podblog/PioneeringAudioblogger.html</link>
<description>Podcasting is an extension of audioblogging.</description>
<enclosure url="http://www.podcastingnews.com/articles/media/Chuck_D_No_Meaning_No_128.mp3" length="640561 " type="audio/mpeg"/>
</item>

</channel>
</rss>

RSS files are used for publishing all types of information on the Internet, but are primarily a tool for sharing web site news. A podcast news feed provides information about the latest shows in a podcast.

RSS files define a channel that contains items. The channel provides meta information about your RSS newsfeed, and describes the your show as a whole. Items are the content of the channel, your individual programs. Each item provides information about one program, in MP3 format, located on your web server.

Channel

The channel element contains metadata that describe the channel itself, including what the channel is and who created it. The channel is a required element that includes the name of the channel, its description, its language, and a URL. The URL is normally used to point to the website associated with this information source.

In addition to the required title, link and description elements, channels can have other optional tags. These include PICS Rating, Copyright Identifier, Publication Date, and Webmaster. For additional information on other Channel tags, look in the RSS specifications.

Image

The image element is an optional element that is usually used to include the logo of the channel provider. The default size for the image is 88 pixels wide by 31 pixels high.

The image's title, URL, link, width, and height tags allow this section to be rendered as HTML. This can provide a "brand" for your news feed.

Items

Items, the most important elements in a channel, contain the content of the channel. While the other elements in the channel are usually static, the news items typically change frequently.

It used to be that channels were limited to fifteen items. This is no longer a requirement, but it's still a reasonable limitation for most uses.

Items require three elements: title, link and description. In typical use, the RSS title is usually rendered as a headline, the description as a one or two paragraph "teaser", and the URL as a hyperlink to the full article or file.

For the purpose of podcasting, an enclosure element is added to the item, like this:

<item>
<title>Rock and Roll Geek Show 3/6/05 Podcast</title>
<link>http://www.americanheartbreak.com/movabletype/archives/000200.html</link>
<description>Chicks dig G.P.S.! Topics: Review of the new GPS for my Treo 600.</description>
<enclosure url="http://gus.to/rrgeek/RnRGeek3_6_05.mp3" length="19921356" type="audio/mpeg" />
</item>

The title is the name of the unique episode of your podcast. The link points to the web page that discusses this individual show. The description is a good place to note what the podcast is about.

The enclosure URL points to the MP3 file for this show.

Text Input

Channels can also contain a text input area, with only one allowed per channel. The purpose of text input sections is to allow users to query or respond to a channel. In HTML, text input areas are rendered a form.

Text input areas are not frequently used. One possible use is to create a form for people to subscribe to your newsletter.

After the four elements, the RSS file must be closed in order to be valid. In the example above, note that the channel is closed, and the there is a closing RSS tag.

The example shown above is in RSS version 0.91. This is an older version of the format, but is still one of the most popular. In addition to being very established, there are many tools for working with version 0.91. There are 1.0 and 2.0 versions that add capabilities. New feeds should probably use the version 2.0. This is especially important for podcasting, because podcasts depend on an element added in the 2.0 spec, enclosures.

Creating RSS files

Creating an RSS file is as easy as taking an example file, opening it up, and entering your own information. In practice, most RSS files are generated by applications automatically. For example, RSS files are generated by almost all blogging programs and services. Open-source tools are available for working with RSS in Java, PHP and PERL.

After you create or generate your RSS file, you should test it to make sure it is valid before publishing it. There are several validation services available online. Just paste in your RSS feed's URL and submit, and the sites will validate your RSS file.

Publish your RSS Feed

After you've validated your feed, you can publish it publicly. Post it to a public area of your site, and provide a link to it. Many publishers use the logo to indicate that an RSS feed for the site is available.

The main purpose of RSS feeds is for content syndication. You publish your content in a standard format, and then anybody in the world and subscribe to your feed and get your news automatically.

In order for people to find out about your news feed, you need to publicize it. In addition to using the XML logo prominently, you will want to submit your RSS feed to the larger RSS directories, and to any niche directories. Submit podcasts to the Podcast Directory at Podcasting News and other sites.

In addition to directories, you may want to submit your site to aggregators. These are services that take RSS content from a variety of sites, collect it and re-organize it into customized formats.

Summary

The simplicity of RSS files make them a good way to publish all types of information. This article has outline the basic concepts behind RSS news feeds. For more information, check out the resources below.

Resources

• The RSS 0.91 Specification is hosted at backend.userland.com.
• The RSS 2.0 Specification is hosted at Harvard.
• Feed Validator provides online validation of RSS files.
• Webreference has good intro to RSS files.
• IBM's Syndication Goes Mainstream is a good discussion of current RSS usage.
• Moreover is an aggregator that features free news feeds from over 1,500 news sources.
• Podcasting News is a good source of information on using RSS for podcasts.