👉 A diode is a semiconductor device that allows current to flow only when an electric current flows through it. It is composed of two p-n junctions, one at the top and one at the bottom, separated by a thin layer of impurities. When a voltage is applied across the diode, a current flows between the p-n junctions, causing them to conduct and create a voltage drop across the diode. This property allows diodes to be used in various electronic circuits for controlling current