What role do diodes play in electrical circuits?

Diodes serve a crucial function in electrical circuits by allowing current to flow in only one direction. This characteristic is fundamental to their operation and is a result of their semiconductor properties. When a diode is forward-biased, it permits electric current to move through it, enabling pathways for current flow in specific parts of a circuit. Conversely, when the diode is reverse-biased, it blocks current, effectively preventing any flow in the opposite direction. This unidirectional property is why diodes are commonly used in various applications, such as rectification in power supplies, signal demodulation, and as protection devices to safeguard other components from reverse polarity or voltage spikes. Understanding this behavior is essential for designing reliable and efficient electronic circuits.