SERIES CIRCUIT- In the diagram above we see a series of identical resistors on a wire in a closed loop. The current through the wire is constant, but the voltage is variant upon the resistors in which it travels. The voltage found across both resistors is equal to one half of the voltage across just one resistor because the resistors are identical and the voltage must be provided for both light bulbs. The equivalent resistance we can find in the circuit is equal to the sum of the values of resistance in Ohms added to each other. Therefore we can conclude that the current is constant across the entire wire as there is not a paralell circuit.
PARALELL CIRCUIT- In the image above we see a paralell circuit. In this circuit there are two equivalent resistors that can be treated with an equivalent resistance acting upon the current of the entire wire. The equivalent resistance can be found by adding the inverses of resistances. Inside the paralell circuit the voltage is constant, but the current varies. We can look at voltage as the capacity to do work.
COMPLEX CIRCUIT- In this complex circuit we have a battery, a switch, and then a series of resistors, two in paralell, and one in a series. The voltage flows from the battery without resistance that sends a current through the wire that feeds the light bulb with electricity. The voltage across the wire adds up to the voltage provided by the battery, but is variant upon the resistance. Voltage "pressure" makes the electrons move, and this "pressure" depends on the resistance in which it travels through, similarly to knotting a hose. The current is constant on the wire outside of the paralell circuit, but inside the paralell circuit the current is reduced because it must feed upon the two light bulbs (resistances) in the paralell. The paralell circuit has an equivalent resistance, and therefore we can treat it as an individual resistor for total current, and voltage. The current through each resistor is not then same, but the current sum inside the paralell circuit is the same as the current that goes through the lone resistor on the wire.
A DC (direct current) is the flow of charge that does not vary in direction. Direct current is used in batteries, solar panels, and when electricity is transported large distances across a wire. This require a closed loop, a switch, and resistors across the wire. In a direct circuit there is a direct flow of voltage.