The circuit in which the current flows in one direction only is the DC circuit. These are the circuits which mostly uses the battery and are found in low-voltage applications. A DC circuit works only if it is closed circuit and stops completely if it is open.
A DC circuit is the circuit in which the flow of electricity is constant from high to low potential. A Direct Electric Current flows only when the Electric Circuit is closed, but it stops completely when the circuit is open.
A circuit is a closed loop through which electrons can flow. A direct current (DC) circuit is a type of circuit with direct current (as opposed to alternating current) flowing through it. That is, in a DC circuit, the current flows in one direction. A DC circuit is powered by a DC battery or other DC-based power source (for example, a battery powering a flashlight).
An electrical circuit is constructed from series and parallel combination of two terminal elements. The two terminal element can be active or passive.
An active element is able to supply energy to the network such as voltage or the current source.
Resistors, capacitors and inductors are passive elements which either absorb or store energy from the sources.
The magnitude and polarity should be specified to describe completely the potential difference or voltage.