Syndication lets sites share information across the Web, making it easy to do things like display headlines from a site or collection of sites. Most of the syndicated feeds are written in RSS, a simple XML vocabulary (in several varieties) for summarizing information about a site. Several popular flavors of RSS are leading the pack, with upstart Atom growing in acceptance. This chapter contains hacks that can help you get a handle on the web site syndication trend.

We start with a hack that explains how to get started subscribing to RSS feeds [Hack #80] , followed by a series of hacks that show you how to create RSS 0.91 [Hack #81] , RSS 1.0 [Hack #82] , RSS 2.0 [Hack #83] , and Atom [Hack #84] documents. Read in succession, these four hacks may seem a little repetitive; however, they are necessary to spell out clearly the formats of each of these vocabularies. You’ll also validate feeds online [Hack #85] .

You’ll learn how to generate RSS feeds with Perl [Hack #86] and with popular blogging software from Movable Type [Hack #87] . You’ll also learn how to post RSS headlines on your own site [Hack #88] and create feeds from Google [Hack #1] and from Amazon [Hack #90] .

Most of the files mentioned in this chapter are in the book’s file archive, available for download from http://www.oreilly.com/catalog/xmlhks/.