What is RSS?

by Mark Kennedy

Oct 2003

RSS is the name of a family of XML formats designed to make it easier for web publishers to share content with others. An RSS file, known as a "feed" or a "channel," generally contains a list of recent articles posted to the publisher's site. This list usually consists of headlines, descriptions, and URLs that point to the complete article.

RSS has been around for several years but has recently gained a higher profile in the world of web publishing. This increased attention is due in part to the emergence of weblog publishing software such as Radio Userland, Movable Type, and Blogger, all of which make it easy for individuals to publish personal web sites that produce and consume RSS feeds.

But RSS has also been adopted by major publishers such as CNET, the BBC, Yahoo!, The Motley Fool, InfoWorld, The New York Times, The Christian Science Monitor, Wired News, and others. These publishers use RSS to distribute their headlines across the Internet, gaining greater exposure for their brand and increased traffic to their site as a result. As more publishers discover the benefits of RSS, its adoption is bound to expand.

Once an RSS feed is published, it can be used by other web sites to integrate the headlines and links into their own content. Or, individuals can use special software to create lists of RSS news sources that are constantly updated with the latest headlines. Other applications, such as specialized RSS search engines, are being developed that aggregate and leverage the information provided by RSS feeds to generate completely new tools and resources on the web.

Why syndicate?

A common question that publishers might have is "why should I syndicate my headlines?" Often, it feels to the publisher like they are giving away their content by providing an RSS feed, and they worry that it will lead to decreased traffic to their "real" web site.

This question usually stems from a misunderstanding of the scope of what an RSS file contains. As explained above, most RSS feeds only provide a headline and a description of each item in the feed, along with a URL that points to the actual article being referenced. If a reader is interested in reading the article they have to follow a link to the URL in order to get the full story. The RSS content really acts as bait that can drive more traffic to the publisher's web site.

For publishers who produce content on a less than regular basis, an RSS feed can be a valuable tool for informing readers when new content is available. Most web users have dozens of sites that they might use on a regular basis to get information. However, most aren't likely to visit each site daily to check for new content. They may stop by once a week or once a month to catch up on the latest news. By the time they get around to visiting each site, the news they find may not be so fresh. RSS can help in this situation. If the user subscribes to your RSS feed, they will see new headlines as soon as they are published in the feed.

How are publishers using RSS?

Most publishers who provide RSS feeds these days are using it to generate a table of contents of the most recently published articles on their site. Often, sites publish multiple RSS feeds, each one geared to a particular subject area or other subset of their content.

For example, the technical publisher CNET produces several different RSS feeds. One is a single feed with all of the latest headlines from its News.com web site, but they also publish separate feeds for individual content categories such as Enterprise Software, Security, Networking, and Personal Technology. The New York Times produces separate feeds for its major news desks, such as National News, Opinion, Arts, Books, and Business. The Christian Science Monitor does much the same thing. Medical publishers MedicineNet.com and MedScape publish RSS feeds targeted at specific health issues, diseases, and medical specialties, such as allergies, Crohn's disease, depression, cardiology, and pediatrics.

While RSS is commonly used to share news headlines, it can be used to publish lists of anything, including press releases, job postings, product listings, and upcoming events.

How are consumers using RSS?

Before deciding to go through the effort to produce an RSS feed, you may be curious about how that feed would be used and who would be using it. In other words, if you build it, who will come?

The first place that you might find your headlines being used is on other web sites that serve as news aggregators or portals. This isn't surprising, considering that RSS originated as a tool for the My Netscape portal to gather headlines for their users. These web sites read multiple RSS feeds on a regular basis and allow users to customize which feeds are displayed or organize the feeds into categories. Examples include NewsIsFree.com and BlogLines.com.

However, a new breed of software tools, known as "news readers" or "news aggregators," has emerged that makes it easy for individuals to collect and manage a personal list of RSS feeds using their own computer. This software lets users subscribe to multiple RSS feeds, organize their feeds into categories, scan headlines, and link to full articles that they are interested in reading. These applications are becoming increasingly common and may end up being as much a part of how people use the Internet as the web browser and the email client. Examples of news reader software includes FeedDemon, Amphetadesk, Radio Userland, NetNewsWire, and NewsGator, which is actually a plugin that allows you to collect and manage RSS news feeds from within Microsoft's Outlook software.

Another less obvious place that an RSS feed might be used is on corporate intranets. A company might include headlines on its intranet from publishers of industry-specific news or other information that might be of interest to the company's employees.

Pitfalls

While publishing an RSS feed is generally a pretty straightforward undertaking, there are a few pitfalls that you might encounter on the way. The first is deciding which version of RSS to support.

There are no less than five different versions of RSS in existence and heated debates have erupted within the RSS community regarding which version should be used. At the risk of oversimplifying, there are two main camps. The first group wants RSS to remain very simple so it can be easily understood and produced by people who are fairly non-technical. These folks tend to refer to RSS as "Really Simple Syndication." The latest RSS version promoted by this camp is RSS 2.0; previous "simple" versions of RSS include RSS 0.90, RSS 0.91 and RSS 0.92.

The other side of the debate is interested in RSS being a bit more robust format that is easily extensible and is based on the Resource Description Framework (RDF), a data description model that allows for fairly sophisticated metadata constructs. This group refers to RSS as "RDF Site Summary." They favor RSS 1.0, which is based on RDF and includes a well-specified mechanism for extending the format to include domain-specific or otherwise non-standard metadata.

The reality is that most RSS tools are capable of reading and parsing any of the five formats. And since all of the formats include similar core elements, transforming one format into another is generally a trivial task. At this point, a publisher is probably best served by generating a feed in either the RSS 1.0 or RSS 2.0 format, or preferably both. The extra effort to produce both formats is negligible, so there's little reason not to do it.

Another potential pitfall stems from the fact that RSS is an XML format, so the feeds need to be well-formed. This is sometimes a challenge for publishers that are more accustomed to the flexibility of HTML as opposed to the rigors of XML.

A quick tour of an RSS feed

There are numerous tutorials on the web that explain the details of the various RSS specifications. Some of them are listed at the end of this article. Rather than duplicate their efforts, I'll just run through the basics of an RSS 2.0 feed to give some sense of the information that it can contain.

An RSS 2.0 feed begins with an <rss> root element with an attribute that specifies that it is version 2.0. The <rss> element contains one <channel> element that contains the details of the feed. The <channel> must contain a <title> element, a <link> element, and a <description> element. The <title> should contain the name that people would use to refer to your channel or web site, the <link> should contain the URL to the HTML web site that corresponds to the channel, and the <description> element should contain a short phrase or sentence that describes the channel.

Here is the beginning of a sample RSS 2.0 feed for CNET's News.com web site:

<?xml version="1.0"?>
<rss version="2.0">
<channel>
<title>CNET News.com - Front Door</title>
<link>http://www.news.com/>
<description>Tech News First</description>

There are several optional elements that can be included in the <channel> element, some of which include elements for specifying the language of the feed, a copyright notice, publication date, and the managing editor.

The heart of an RSS 2.0 feed is the series of one or more <item> elements contained within the <channel> element. Each <item> element refers to one article, or whatever type of content is carried in the feed. All elements within the <item> are optional, but there are three elements that are generally included: <title>, <link>, and <description>.

The <title> element usually contains the headline for the article being referenced. The <link> element contains the URL where the article can be found. And the <description> element should contain a short one or two sentence summary of the article.

There are several other elements that can be contained by an <item> element, including elements for the author, a publication date, a category, among others.

Here is an example of an <item> element that includes all of the elements described above:

<item>
  <title>Toshiba offers notebook trio for small business</title>
  <link>http://rss.com.com/2100-1044_3-5094335.html?part=rss&tag=feed&subj=news</link>
  <description>The notebook maker beefs up its line of notebooks for small and medium- size businesses by adding a trio of Satellite models.</description>
</item>

Note that these samples are not actual examples of CNET's RSS feeds. They have been simplified for demonstration purposes. The actual CNET feeds contain a richer set of metadata using many of the optional RSS 2.0 elements. A complete RSS 2.0 feed can be found on the News.com web site.

As you can see, the basic elements of an RSS feed are easy to generate. If your web site uses even a very basic content management system, you can probably generate an RSS feed with minimal effort. Even if someone had to hand-code the feed, it wouldn't take much effort at all—it would probably just be a matter of copying and pasting content from an HTML file into the XML file.

The future of RSS and Web syndication

I'm bullish on the future of RSS and web syndication in general. I'm convinced that as more and more consumers are introduced to news aggregation tools, their popularity will continue to increase. For people who regularly check more than a handful of web sites on a regular basis, the utility of aggregators is quite compelling. As their popularity increases, they'll become the source of more and more traffic to web sites, so making RSS feeds available will be increasingly important to web publishers.

It seems to me that the likely course for news aggregation software is for their functionality to be consolidated into more common tools such as email clients or the web browser. Most users won't be interested in yet another piece of software to learn, so if they can get similar functionality in an already familiar tool, that will have great appeal. I expect software companies to make future versions of their products capable of generating and consuming RSS for various purposes.

We'll probably start seeing more and more data-oriented RSS feeds become available as time goes by. One site, RSSWeather.com, is experimenting with providing weather forecasts in an RSS feed. I can imagine subscribing to an RSS feed of television listings from my local cable provider, or an RSS feed of real estate listings from my realtor, or an RSS feed of recent charges to my credit card. There are many similar possibilities and publishers would be smart to think of innovative ways that they could flow their data to potential customers via RSS.

I also expect that we'll start seeing more and more RSS feeds including advertising within the feeds. Due to the limitations of the format, though, the ads will probably resemble Google's AdWords more than they will the popups or banner ads that have proliferated on most commercial web sites in the past few years, which is a good thing. But including advertising could create one thing that RSS has been missing for the most part: a revenue model. However, I don't think that advertising is the only way to make a buck off of RSS. Customized RSS data feeds could be something that customers may be willing to pay for in the future. In the end, though, most RSS feeds will continue to be freely available and considered mostly a mechanism to attract more visitors to a publisher's traditional web site.

The biggest question that I think remains to be answered is whether or not some new format will come along to supplant RSS as the predominant format for web syndication. There is a project currently underway to do exactly that. Known as "Atom," the project aims to create "specifications for syndicating, archiving and editing episodic web sites." Participants hope to improve upon the success of RSS by providing a more robust set of specifications for syndication and related tasks. While RSS may not be around forever, an investment in it today will be well worth the effort and will pave the way for supporting future syndication formats as they are created.

One interesting area to watch is whether RSS feeds will start to take the place of email newsletters. Several people have suggested just such a thing, and I think there is quite a bit of merit to the argument. The thinking is that email publishing today suffers from numerous liabilities that RSS doesn't have. For example, email is a conduit for spam and viruses, two of the modern Internet's most annoying plagues. RSS, on the other hand, is (so far) immune from these issues, mainly because it relies on a "pull" model instead of the email "push" model. If a reader feels that a publisher of an RSS feed has abused the relationship in any way, the user can easily unsubscribe and never deal with the publisher again. A more detailed discussion of this topic can be found on the Lockergnome web site. It's written by Chris Pirillo who has built a small empire based on publishing email newsletters. For him to be advocating the move from email to RSS is worth noting.

Additional reading