Most simple incandescent light bulbs are made of a thin section of tungsten through which the current flows. This section of tungsten is called a "filament". The tungsten filament has electrical...
An incandescent bulb is 96% efficient as a heater, and 4% efficient as a source of light.
A fluorescent bulb is only 60% efficient as a heater, and 40% efficient as a source of light.
An LED bulb...