An RSS reader is a web-based RSS reader accessible via any web connected device. The reader uses RSS web URLs to periodically visit a site and check for new information. When new information is found (for instance a new article or blog post), the reader logs the RSS data and stores it for your attention.
Some websites pass along a wealth of information in their RSS data, and some pass short synopsis data. Website owners decide how much or how little RSS information to share with the reader