What does P(superscript)4 represent and how is it different then 4P

I'm so stumped!! I have no idea how to explain it.....

P4 is a molecule, composed of four phosphorus atoms chemically bonded together. The P4 molecule moves about in space an one unit, all 4 atoms in the molecule moving together.

4P means that there are four phosphorus atoms present. Each atom is separate from the other three and each atom can move about independently of the other three.