How does alternating current (AC) differ from direct current (DC)?

Alternating current (AC) is characterized by the periodic reversal of direction, which means that the flow of electric charge changes direction at regular intervals. This is in contrast to direct current (DC), where the electric charge consistently flows in one direction only. The periodic nature of AC is why it is commonly used in power grids and household electrical systems, allowing for efficient transmission of electricity over long distances.

The fact that AC reverses direction means that it can be transformed to different voltages more easily, making it suitable for distribution and various applications. Understanding this fundamental difference helps in grasping how electricity operates in different environments and the practical uses of each type of current.