Adaptive vs. Responsive, what’s the difference?
“Responsive design” is a subset of a larger concept which is called “Adaptive design”. When talking about responsive we refer to the layout only (Ethan Marcotte, fluid grids, flexible images & media queries).
“Adaptive design” on the other hand includes much more than just fluid layout. In practice it means the same thing as progressive enhancement, which means in short, that we aim to deliver the best possible experience to the widest possible audience. Also: “Adaptive design” shouldn’t be mixed with “Adaptive layout” which is a completely different thing.