Light emitting diodes, commonly called LEDs are basically tiny light bulbs that don't have a filament that will burn out and don't get especially hot. They are illuminated solely by the movement of electrons in a semiconductor material, and they last just as long as a standard transistor. The past few years have brought about the development of LED light bulbs which can replace many of the bulbs that are commonly used today in our homes. These relatively new type bulbs have an extremely long life and are low in power consumption. Although technology is always improving, as of now LED light bulbs have lower output (lumen) than incandescent bulbs, but are more focused. For the time being, they are used mainly for directional lighting, but this can change at any time.