Abbreviation for Light Emitting Diode. It is not an acronym. You do not pronounce it as “lead.” It is pronounced EL – EE – DEE. An LED is an electronic component that glows when current passes through it. LED’s are found in all sorts of electronic equipment these days from watches to laser disc players (in fact the laser that reads the disc is usually an LED). The lights that glow on top of your keyboard are almost surely LED’s. The numerical readout and meters on your DAT machine are almost surely LED’s. LED’s do not always produce visible light. Infrared LED’s are used in wireless remote control devices as well as things like wireless headphone systems.