A P-N junction diode is formed by placing a P-type semiconductor next to an N-type semiconductor, creating a junction. When the materials are joined, electrons diffuse from the N to the P side and holes diffuse from the P to the N side, creating an area devoid of carriers called the depletion region. A P-N junction diode conducts electricity easily in one direction when forward biased but acts as an insulator with little current when reverse biased, making diodes useful for rectification. Key parameters for using diodes include the forward voltage drop, reverse breakdown voltage, and maximum operating temperature. P-N junction diodes have a vast range of applications from power supplies to displays.