Our technological world has become deeply dependent upon the continuous availability of electrical power. In most countries, commercial power is made available via nationwide grids, interconnecting numerous generating stations to the loads. The grid must supply basic national needs of residential, lighting, heating, refrigeration, air conditioning, and transportation as well as critical supply to governmental, industrial, financial, commercial, medical and communications communities. Commercial power literally enables today’s modern world to function at its busy pace. Sophisticated technology has reached deeply into our homes and careers, and with the advent of e-commerce is continually changing the way we interact with the rest of the world.