A first order approximation of a wire, is that all points along the length of the wire are a single point, and therefore, any given circuit can be stretched and distorted into an almost limitless number of shapes. These two Wall Warts (a wall wart is a power supply that plugs directly into the wall outlet, usually providing a relatively, safe, lower voltage, usually DC, and in the range of 3 to 20 volts) the two Wall Warts shown are electrically identical, even though they look very different. The grounds, since they represent a wire, are also readily adaptable, the other circuit has no grounds, nor, other symbols substituting for wires, such as the "(+) 12 volts" symbol.