Field-Effect Transistors (FETs) are three-terminal semiconductor devices that control the flow of current using an electric field. Unlike BJTs, FETs are voltage-controlled rather than current-controlled, offering high input impedance and low power consumption. Available in types like JFET (Junction FET) and MOSFET (Metal-Oxide-Semiconductor FET), they are commonly used in amplifiers, switching devices, voltage regulators, and digital circuits. FETs provide fast switching, high efficiency, and excellent thermal stability, making them ideal for both analog and digital applications in computers, communication system