RSS stands for Really Simple Sydication. It is used to publish frequently updated tasks over the internet like blogs, news, audio, video etc. They are also called feeds. Besides, there are feeds shared as digital media files that are known as podcasts and are released episodically in a regular manner and are downloaded via web syndication. The feeds are read via RSS readers or feed aggreagators. Google Reader, Newsgator, Netvibes, My Yahoo are some of the popular feed readers. But many people have switched to Google Reader from the others as it is more advanced and easier to use. Desktop feed readers are also available.
RSS includes full text and also the metadata which holds information like the date of publication, author’s name etc. There is a standard XML file which is used for publishing and making it possible for many people to read it via their feed readers. Here is a video that will explain you some major things about RSS.