XML stands for EXtensible Markup Language and it is a simplified subset of Standard Generalized Markup Language (SGML). Its primary purpose is to facilitate the sharing of data across different information systems, particularly systems connected via the Internet.
RSS is a Web content syndication format. Its name is an acronym for Really Simple Syndication. In other words, RSS is a lightweight XML format designed for sharing headlines and other Web content. More details about RSS 2.0 specification can be found athttp://blogs.law.harvard.edu/tech/rss.