RSS is the acronym for several things:
Rich Site Summary
Real Simple Syndication
RDF Site Summary
In a nutshell, RSS is the syndicated content from a web site. It can consist of both the direct content itself, as well as the metadata (or, information about the information -- much like a library catalog record!).
RSS uses XML formatting to create RSS feeds.

Therefore,
You will want to use a news reader (or aggregator) to translate the content of an RSS file, because the RSS Feed is basically tags and endtags -- much like an HTML document.
An example of an RSS text file...

Source: Hammersley, Ben. Content Syndication with RSS.
Farnham: O'Reilly, 2003: 1.