Electricity is a major service that enters the home. This article will describe a basic electrical system and the different fittings and connections associated with it. It will also prompt you to think about the planning of rooms for electrical requirements as an interior designer.The electricity supply that enters your home will either be 230-240 volt or 110-120 volt system. For an interior designer’s purpose the type or size of the current is irrelevant, we are concerned with how the electricity is distributed throughout the house and the fittings that use it.