From Joomla! Documentation
These options control the display of news feeds.
- Show Feed Link. (Hide/Show) Whether to Hide or Show a link to a news feed (RSS Feed). If set to Show, a Feed Link will show up as a feed icon in the address bar of most modern browsers.
- For each feed item show. (Intro Text/Full Text) If Intro Text, only the article's intro text will show in the feed. Otherwise, the entire text of the article will show.
- Show "Read More". (Hide/Show) Hide or Show a "Read more" link in the newsfeed.