1. RSS Really Simple Syndication

2. Overview RSS is a web content syndication format RSS documents are XML and must conform to the xml 1.0 recommendation RSS files are used to keep subscribers informed about the most recent updates to news, blogs, discussion groups, site postings, etc.

3. Versions of RSS First began as scripting news in 1997 RSS 0.90 was designed for use with Netscape 1999(had an RDF header) RSS 0.91 (1999) more standard, no RDF header RSS 0.92 which is 0.91 with optional elements RSS 1.0, Developed by a private group at O’Reilly –again has an RDF header (2000) RSS 2.0 –basically a modification of 0.92 (2003)

4. Basics of RSS 2.0 The root element of the document is It has no namespaces, though namespaces can be added to accommodate extensions to rss and inclusion of other xml vocabularies The element has a single child, the element

5. The Element The element can contain several elements. Most contain metadata about the rss feed Three elements are required and several are optional Additionally the element contains one or more elements The elements contain the description and links of the syndicated content

6. Required Elements of Required Elements of ElementDescriptionExample titleThe name of the channel NPR topics: News linkThe URL to the website corresponding to the channel http://www.npr.org descriptionA few words describing the channel Current news stories from NPR

7. Optional Elements of Optional Elements of ElementDescriptionExample languageThe language the channel is written in en-us copyrightCopyright noticeCopyright 2007 NPR managingEditorEmail address for person responsible for editorial content spconger@npr.org webMasterEmail for the web master george@mycom.com pubDatePublication date. Conforms to RFC 82 Sat, 07 Sep 2002 00:00:01 GMT lastBuildDateDate of last buildSat, 07 Sep 2002 00:00:01 GMT categorySpecify one or more categories that the feed belongs to Science

8. Optional Elements Continued ElementDescriptionExample generatorA string indicating the generator used to generate the channel MightyInHouse Content System v2.3 docsA URL that points to the documentation for the format used http://blogs.law.harvard.edu/tech/rss cloudAllows a processor to register with the cloud to be notified of updates to the channel ttlTime to live in minutes 60 imageSpecifies an image that can be displayed with the feed

9. Optional Elements (End) ElementDescriptionExample ratingThe PICs rating for the channel textInputSpecifies a text input box that can be displayed with the channel skipHoursA hint for aggregators about what hours they can skip skipDaysThe same for days

10. The Element A channel many contain any number of items The items may represent a link to a story or a resource or they may be complete in themselves All child elements of are optional however at minimum at least a title or description must be present

11. Elements of Elements of ElementDescriptionExample titleThe title of the itemMars Phoenix successfully lands near polar ice cap linkThe URL of the itemhttp://www.nasa.gov /mars/phoenix descriptionThe description of the item (can contain entity escaped html) At 5:45 this afternoon eastern time the Phoenix probe entered the Martian atmospher authorEmail address of the author categoryIncludes the item in a category

12. Elements of Continued ElementDescriptionExample commentsURL for a page of comments related to the item enclosureDescription of media object attached to item guidString that uniquely identifies the item http://inessential.co m/2002/09/01.php#a 2 pubDatePublication date of the item sourceRss channel that the item came from

13. RSS Example Channel Metainformation Lift Off News http://liftoff.msfc.nasa.gov/ Liftoff to Space Exploration. en-us Tue, 10 Jun 2003 04:00:00 GMT Tue, 10 Jun 2003 09:41:01 GMT http://blogs.law.harvard.edu/tech/rss Weblog Editor 2.0 editor@example.com webmaster@example.com 5

14. RSS Example Items Star City http://liftoff.msfc.nasa.gov/news/2003/news-starcity.asp How do Americans get ready to work with Russians aboard the International Space Station? They take a crash course in culture, language and protocol at Russia's Star City. Tue, 03 Jun 2003 09:39:21 GMT http://liftoff.msfc.nasa.gov/2003/06/03.html#item573 Space Exploration http://liftoff.msfc.nasa.gov/ Sky watchers in Europe, Asia, and parts of Alaska and Canada will experience a partial eclipse of the Sun on Saturday, May 31st. Fri, 30 May 2003 11:06:42 GMT http://liftoff.msfc.nasa.gov/2003/05/30.html#item572

15. Reference Much of the material for this slide show came from http://cyber.law.harvard.edu/rss/rss.html Theirs is the definitive document for defining RSS 2.0