the most commonly used circuits in electronics is the DC circuit.
A series circuit provides only one path for current flow.
A parallel circuit is defined as a circuit having more than one current path.
Most circuits consist of both series and parallel circuits. Circuits of this type are referred to as series-parallel circuits
One of the more common uses of resistors is voltage division, which is used extensively in electronics. Voltage dividers are often used to set a bias or operating point of various active electronic components such as transistors or integrated circuits. A voltage divider is also used to convert a higher voltage to a lower one so that an instrument can read or measure a voltage above its normal range. This often referred to as scaling.