My name is Emma Yohannan and I am an eighth grader at Carl Sandburg middle school. The incandescent light bulb is a source of electric light that works by incandescence. An electric current is passes through a thin filament, heating it until it causes a light. The enclosing glass bulb prevents oxygen in air from reaching the filament. Incandescent light bulbs are not energy efficient; they waste most of the energy they use. Only 10% of the energy is used for light while the other 90% is used for heat, this is a problem. At the least it should be 50-50. I feel that incandescent light bulbs are ruining our environment and I advise people to use otherwise. Thank you for your time.