How does AC current differ from DC current?

AC current, or Alternating Current, is characterized by its ability to change direction and magnitude periodically. This means that in an AC system, the voltage can swing from positive to negative, leading to a flow of electric charge that moves back and forth rather than consistently in one direction. This characteristic is fundamental to how electricity is transmitted across power grids because it can efficiently power transformers and allows for long-distance energy transmission with relatively lower energy losses.

In contrast, DC current, or Direct Current, flows steadily in one direction and maintains a constant magnitude without the oscillation seen in AC. Understanding this fundamental difference helps in applications ranging from home electricity supply to various electronic devices, where each type of current is utilized based on the required characteristics for operation. Knowing these distinctions also clarifies why certain power systems and devices are designed specifically for AC or DC, depending on efficiency and functional requirements.