What type of electrical current flows in only one direction?

Direct Current is characterized by the flow of electric charge in a single, unidirectional stream. This means that electrons move consistently in one direction, which is essential for many electronic devices and applications, such as batteries, solar panels, and electronic circuits. The steadfast flow of electricity in one direction allows for predictable performance in devices reliant on stable power supply.

Alternating Current, by contrast, flows in both directions, changing its direction periodically. This is commonly used in household power supplies because it can be transmitted over long distances more efficiently. Variable Current is not a recognized standard type of current and typically refers to systems or applications where the current may change amplitude but doesn't define a specific direction. Residual Current is related more to leakage current that occurs in electrical installations and often pertains to safety devices like RCDs or ground fault circuit interrupters, which serve to prevent electric shocks.

Understanding the distinct characteristics of Direct Current helps in identifying its importance in applications where stable and consistent power is crucial, distinguishing it clearly from the other types of current mentioned.