Feeds encouraged the development of several applications for their consumption. Modern web browsers
(including Internet Explorer 7 and Firefox 2.0), desktop applications such as Microsoft Office 2007, and
web applications such as Google Reader (
) allow users to access the
feeds they subscribe to from one convenient location. These applications are called aggregators, or feed
Your web site can provide access to some or all of its content through web feeds. They may include links to
the actual content as well as other links to elsewhere within your site. Over time, this will garner traffic and
links from users who subscribe to your feeds, as well as the various sites that
permits other web sites to promote your content. Other webmasters have an incentive to
syndicate feeds on their sites as fresh content, because including relevant syndicated content in
can be a useful resource. It may, however, be wise to abbreviate the amount of information you provide in
a feed, because the
content appearing on various sites may present duplicate content problems. You
may also choose to syndicate others web sites’ content.
Moderation means that the web site could stand on its own without the syndicated content as well. If it
cannot, it is probably a spam site.
Today, all major blogging platforms provide feeds of some sort. Most other types of content manage-
ment systems provide them as well. The custom applications that you develop may also benefit from
their addition. This chapter demonstrates how to do so.
In order to be usable by everyone, feeds must be provided in a standardized format. RSS and Atom are
the most popular choices.
RSS and Atom
Unfortunately, as usual, there are the requisite format wars. There are many competing formats for web
syndication. Two of them are discussed here — RSS and Atom.
Both RSS and Atom are XML-based standards. The virtue of XML is that it provides a common frame-
work that applications can use to communicate among multiple architectures and operating system
platforms. RSS and Atom feeds can be viewed as plain text files, but it doesn’t make much sense to use
them like that, because they are meant to be read by a feed reader or specialized software that uses it in
the scheme of a larger application. Figure 7-1 shows Jamie Sirovich’s SEO Egghead feed in Cristian’s
Google Reader list.
RSS has a long and complicated history, with many versions and substantial modifications to the stan-
dard. There are two fundamental branches of RSS with two different names. RDF Site Summary (RSS 0.9)
was created by Netscape in the late nineties. In response to criticism that it was too complex, a simpli-
fied and substantially different version, RSS 0.91, was released. To make things even more interesting,
RSS 1.0 is largely a descendant of RSS 0.9, whereas RSS 2.0 is closer to RSS 0.91. RSS 2.0 now stands for
Really Simple Syndication
, and RSS 1.0 still stands for RDF Site Summary. Because this is not a history
book on RSS, we will stop here and state that RSS 2.0 is by far the most popular and most adopted at
this point. The standard is also now frozen, and no new changes are underway. The standard for RSS
2.0 is located at
Chapter 7: Web Feeds and Social Bookmarking
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