What is the difference between plush, pillow-top, and Euro-top designs?

"Plush" describes how soft the mattress feels, while "pillow-top" and "Euro-top" describe how an extra top layer is constructed. Pillow-tops have a distinct, separate-looking layer, while Euro-tops are more flush with the mattress edges. All three can be made in softer or firmer versions depending on the materials used.