What is the difference between a polarized and non polarized power cord?

A device with a polarized power cable has a NEMA 1-15P socket with prongs corresponding to the output. It will only go in one direction. A device with a non-polarized power cable also has a NEMA 1-15P socket, but the prongs are the same, so it can go in both directions. A NEMA 1-15P on the ground has three prongs.An appliance with a polarized power cord has a plug that matches the outlet. Only one way will it travel. An appliance with a nonpolarized power cord has a NEMA 1-15P plug, but the prongs are the same, so it can go either way. There are three prongs in a grounded NEMA 1-15P.