The word 'responsive' has been sprayed all over these pages. I take it I'm supposed to read that word a certain way in this context, but I don't know how. Does it mean you can click things? Something more? Something else?
Backing up what ricefield said, responsive design is making something that works well in many different viewing contexts (desktop, mobile, tablet, smart TV, etc). http://zurb.com/word/responsive-web-design
See: http://en.wikipedia.org/wiki/Responsive_web_design