Enhanced realism improves the realistic impression of a model by casting shadows of the model on a plane and on the model itself. The reflection of a virtual environment that is defined by an "Environment Map" on the model's surface makes the model appear more "shiny". The mirror floor plane also reflects the model like a mirror as shown in the following image. The shadows and reflection happen in real time without activating the high-end rendering display. The mirror floor shown is a grid. See Change viewport settings.

You cannot use phong shading and shadow generation on systems that are not equipped with programmable graphics hardware.