Writing Semantic Markup
“The biggest and most welcome change on the Web in the last five years has been the astronomical growth of Web feeds: XML files containing a snapshot of a Web site%u2019s newest content that saves readers a tremendous amount of time. In 2000, there was only a handful of feeds. In 2005, there are millions.
In Web 2.0, the Web as platform, Web feeds are a simple way to share and receive content. If we think of a Web URL as a really simple interface for requesting information%u2014a simple application programming interface (API)%u2014then a Web feed is the simplest responses we can receive. We type in a feed URL and receive the content that is there%u2014usually the last 10 items added to a Web site.”
full article at digital-web.com