Components of an electrical circuit or electronic circuit can be connected in many different ways. The two simplest of these are called series and parallel and occur very frequently. Components connected in series are connected along a single path, so the same current flows through all of the components.Components connected in parallel are connected so the same voltage is applied to each component.
A circuit composed solely of components connected in series is known as a series circuit; likewise, one connected completely in parallel is known as a parallel circuit.
In a series circuit , the current through each of the components is the same, and the voltage across the components is the sum of the voltages across each component.In a parallel circuit, the voltage across each of the components is the same, and the total current is the sum of the currents through each component.