RSS link?

Hello, Under Theme Opitons > Social Links > Predefined Social Icons I see a fiend for RSS. What do I enter in this field? I tried entering my blog URL, but then clicking the button just takes me to the exact same page. I still dont have my head wrapped around RSS, but I thought this button should allow a person to subscribe to my blog? If so what should I enter into the field? Thanks for your time Keir