A light-emitting diode (LED) is a semiconductor device that converts electrical energy directly into light through the process of electroluminescence. Functionally, it consists of a p-n junction formed by two types of semiconductor material: p-type, which has excess positive charge carriers (holes), and n-type, which has excess negative charge carriers (electrons). When a suitable voltage is applied across this junction, electrons from the n-type material migrate to the p-type material, where they recombine with holes. This recombination process releases energy in the form of photons, producing light. LEDs are prized for their high energy efficiency, durability, and operational longevity, making them widely utilized in applications ranging from general illumination and display backlighting to specialized signaling and indicator lighting.