What is the primary difference between direct current (DC) and alternating current (AC)?

The primary difference between direct current (DC) and alternating current (AC) lies in the direction of electron flow. In a direct current system, the electrons flow in a single, constant direction. This unidirectional flow is typical for systems powered by batteries and many electronic devices, where a stable voltage is desired.

In contrast, alternating current involves the flow of electrons that periodically reverses direction. This means the current alternates, which allows for the efficient transmission of electricity over long distances and is commonly used in household power systems. The alternating nature of AC enables it to be transformed into different voltage levels more easily, making it a more versatile choice for widespread electrical distribution.

Understanding this distinction helps clarify how different electrical systems function and highlights the unique applications of DC and AC in various technologies and infrastructures.