The 60 Watt incandescent light bulb is perhaps the most popular light bulb found in homes. Incandescent
light bulbs make electricity by heating a metal filabment wire to a hight temperature until it glows. The
filiment is protected from burning or oxidizing because the bulb is filled with an inert gas or is evacuated.
Incandescent light bulbs waste much of the power fed into them through the output of heat, and are therefore
less efficient than other types of light bulbs.
In the USA, federal law has scheduled incandescent light bulbs to be phased out by 2014.