A pre-finished floating floor isn’t directly attached to the subfloor. It has a foam underlayment on top of the subfloor to absorb sound and protect against moisture; the hardwood strips or planks are then laid on top. The flooring is glued or locked together with tongue and groove joints and the entire floor “floats” above the subfloor. It’s easy to install on nearly any surface. The “cushy” feeling you may sometimes feel with floating floors can be reduced or eliminated by ensuring your subfloor is as flat as possible using floor leveling products and a quality underlayment.
Since wood flooring expands and contracts seasonally, be sure to always leave an expansion gap around the perimeter of the floor following the manufacturers installation instructions. (This gap is hidden by baseboard and base shoe and allows the floor to move without creating high spots or buckling).