If an outlet has a third wire called a ground wire, it is a grounded receptacle, or outlet, and will have the familiar three slots. A ground wire is an important safety feature. If your home’s electrical system, or an individual outlet, get a surge of excess electricity, this can raise the risk of fire, shock, or electrocution. This power surge, also called an electrical fault, travels from the grounded electrical outlet back to your home’s main electrical panel, out through the ground wire to the earth, which absorbs the excess energy. By directing the power surge to the earth, the ground wire reduces the risk of damage to your appliances and injury to you and your family.