It allows you to syndicate your content to other sites. Other sites can then display the content within areas of their own site. In terms of link building that can be very beneficial. Lets say you place your recent articles within your RSS feed, and other sites display your content. You might only show a small section of the content then a link to your site in order to read the full article. This can lead to links and click through traffic from uses wishing to read the article in its entirety.