What is the function of a diode in an electrical circuit?

A diode is a semiconductor device that primarily functions as a one-way valve for electric current, allowing it to flow in only one direction. This property is known as rectification. When forward-biased, the diode conducts electricity, allowing current to pass through. However, when reverse-biased, it blocks the current, preventing it from flowing in the opposite direction.

This directional flow is crucial for various applications, such as in power supply circuits where it is essential to convert alternating current (AC) to direct current (DC). The diode effectively protects sensitive components by ensuring that current always flows in the intended direction, which contributes to the stability and functionality of electrical circuits.

While diodes can perform additional roles, like acting as rectifiers or clamp devices, their primary and most fundamental function remains the control of current direction.