The dark art of XML has really begun to change the way we use the Web. While creating an extensible markup language document is more complex than HTML, its virtue is that files marked up this way are much easier to share.
As a consequence, a number of major players, including US news sites, the UK's BBC and portals such as Yahoo, are willing to provide links to their regularly updated content using really simple syndication (RSS). This drives traffic to their sites and enables you to include rolling news links with minimum fuss.
RSS began life as the Rich Site Summary format, a specification used by Netscape, among others, to distribute content channels using the charmingly entitled Resource Description Framework, or RDF. RSS, now in version 2.0, was renamed Really Simple Syndication to draw attention to what, by 2002, had become its main function: syndicating or exchanging content between Web sites and blogs.
RSS repackages the content of a site as a list of data items, such as a news story and a link to it. With a program known as a news aggregator or feed reader - such as NewsGator (see screen shot), or the Sage plug-in for Firefox that Will mentioned last month - you can check whether content has been updated without having to visit the site first. Links to new material are simply listed in the feed reader.
For Web developers, this means you can embed these into your Web pages to provide rolling content, or specify your own documents as RSS-compatible so that they can be checked by aggregators.
RSS has established itself as the main technology for linking to news stories and content, but this year Google announced that its Blogger service was to use an alternative: Atom. Part of the problem - for Google, at least - appears to be that development of RSS 2.0 has been frozen in order to truly keep it simple.
For Google and some other developers, this has prevented RSS from turning into a really exciting technology. In particular, Atom has been used to simplify the process by which blogs and wikis (online collaborative databases) can be syndicated, enabling users to more easily share information that they load on to such forums.
The potential problems are twofold: the first, initially more irritating, issue is a technical difficulty in ensuring that different newsreaders will work with RSS and Atom. You can find a list of compatible readers at www.atomenabled.org. The Atom/RSS conflict is already being resolved by feed readers that can interpret both standards.
Further confusion, however, stems from the fact that the versions of RSS most commonly used are 2.0 or 0.9x - but there is a third: RSS 1.0. Unfortunately, this is based on the W3C's rich data format standard (confused yet?), which is a more powerful implementation of XML but also more difficult to use.
On a roll
When you load Feedroll into your browser, it displays a drop-down menu with a list of popular content providers such as Amazon, the BBC and Yahoo (see this picture). Select one of these and click Update to display a sample list of links.
Once you have chosen an appropriate source, scroll down the browser window to customise how links will be displayed in your page. Here you can set such things as text size, colour and whether links are opened in new windows - useful if you don't want to drive visitors away from your site. After making appropriate changes, click on Update.
Feedroll takes your source and formatting options and converts them into a script that you literally cut and paste into your own document (see heret). When you preview your page in a browser, it will automatically load links from the syndicating site, providing you with regularly updated links to some of the world's best content.
Sites to see
Feedroll is the site we recommend to automate RSS content to add to your site, but if you are looking to find out more about it, such as links to feed readers, blogs and tutorials on syndication, visit www.Syndic8.com. As well as free tools and information, there are extremely useful lists of sites here - such as Slashdot and Wired - that offer content via RSS.
Your starting point for info about RSS feeds, as well as finding free content and syndicating your own.
Syndicating your own material
As well as incorporating third-party content into your Web pages, a valuable use of RSS is to share your own data with other Web sites and aggregators. If you add new content regularly, this can be a reliable way of informing visitors who use aggregators or shared feeds on like-minded sites that there is new stuff worth viewing.
There are alternative versions of RSS, but the rather crude facilities of RSS 0.9x will be enough to get you started using Really Simple Syndication. The important tags are
< rss version="0.91" > < channel > < title > My news site < /title> < link > http://www.mysite.com < /link > < description > All the best news from my site < /description > < item > < title > My first story < /title > < link > http://www.mysite.com/news1.html< /link > < description > My first news story < /description > < /item > < /channel > < /rss >
The channel sets up a feed for your site and is the container for all RSS data. You can add as many items to appear as links in an aggregator as you like, but there is only one channel. Once you have created your RSS file, use an RSS validator (there's one at http://rss.scripting.com) to check your feed, then inform people of its existence. Put an XML button or text link on your site or advertise on feed directories such as www.Syndic8.com (see "Sites to see"). Of course, every time you update your site you'll need to update the RSS file, but then visitors will know at a glance that it has been changed.