Kirchhoff's laws are used to help us understand how current and voltage work within a circuit. They can also be used to analyze complex circuits that can't be reduced to one equivalent resistance using what you already know about series and parallel resistors. By using these laws, we can find the unknown resistances, voltages and currents (direction as well as value). In the branch method, finding the currents through each branch carried by applying KCL at every junction and KVL in every loop of a circuit.