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Across the world power utility companies provides us electricity in different formats but fundamentally they are all the same. From the power station driven by – hydro (water), coal/steam or nuclear the alternators come with three lines (phases) with high voltage, which will first be stepped up using transformers, enabling efficient transporting over kilometers, then dropped via transformers to usable/safer levels of voltages .e.g. 33000Volts dropped to 11000V then 6600V and finally to 400V for all IEC counterparts. For the USA it’s not so easy. They have 110V or 240 V appliances mixed (ref: NEC). Having started with 120/240 volts (That’s another history lesson, straight from Mr. Edison) they now have to contend with a dual system three-phase 240V(from where the domestic 110V is derived from) and 480V (from where the contemporary 240V is derived from. In any case, as a universal rule, the last “delivery” transformer has the phases connected in a radial formation deriving a common connection point between the windings. This is referred to as a star connection. With this star configuration, between each phase and the common connection point, three separate single-phase loads can be powered from one transformer. In reality, it means:- In a suburb, all three lines are run down the street and for each single phase house one phase + the common neutral is tapped.  Power distribution
But then, Mr. Edison was right about one thing – and Topsy the elephant died in 1903, dogs, calves and a horse died in experiments in those days, to prove exactly this point. If contact was made, to any point of the electric circuit, one will surely not be same again. At the very least the hairdo will definitely undergo a serious change towards the heavens. So what can be done to make it safer by at least 50%. An ingenious idea was conceived: – What will happen if this common connection is connected to the ground? This high (floating) potential, with respect to earth will now be 0V, thereby removing the potential for electrocution.
So, it is by no accident this connection type is referred to as grounding (USA) or earthing (Europe). This means that, in some way or another, one side of every single phase load like lights, whatever in your house/office is bound – quite literally to the ground – so it makes it much, much safer for all. We now have two conductors that seem to do the same job: The earth (ground conductor) and the neutral (common to the three phases). For some, it might look like they do the same job, and for others, it might even look like the earth serves no purpose! The neutral is the return conductor and the earth is there to save a life. This then explains basic electrical reticulation concepts as it is done across the world.  Grounded single phase supply
=== Shall we delve deeper into circuit breakers here, or do it in another post? Another post it is.
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