Why does my Dewalt power drill only have a 2 prong plug?
Unless it is very old, it is "double insulated." That means the electrically conductive parts and wires are insulated form the metal parts of the motor and the metal parts of the motor are completely covered by the insulating case of the drill. There should be a box inside a box symbol on the product to indicate that it is double insulated. A double insulated product without a ground is supposed to be just as safe, perhaps safer, than a grounded product.