Have you ever wondered why the bulb in your desk lamp gets extremely hot? Inversely, have you ever thought: how do fluorescent lights manage to stay so cool? Incandescent bulbs, often viewed as the "traditional" ones with their classic pear shape, are actually technologically outdated. The reason we know to keep ourselves from placing our fingers on that bulb is because incandescent lighting produces mass amounts of heat, a heat so intense that it glows. Sure, they're very bright, but also very wasteful and electrically inefficient. With the passing of a gargantuan energy bill, the U.S. attempts to save energy by getting the ban on Thomas Edison's invention moving in 2012, with a complete ban taking effect in 2014.
When you flick on a light switch, you are activating a circuit, which passes electricity into a copper wire (which is attached to the filament within the bulb). The electrical energy meets the filament (made of tungsten which can endure vast amounts of heat and remain in tact), and undergoes a reaction most simply explained by "electron excitement" due to the property of the coiled filament. This excitement of electrons heats up the filament, converting what was first electrical energy to thermal energy. This thermal energy is then converted to light energy in the form of a glow. The problem: only approximately 10% of the original electrical energy input is converted to light. The rest is lost as heat.
Essentially, congress wants to replace incandescent lights with more efficient forms of lighting (like florescent lights). In 2012, 100-watt incandescent lights will be phased-out, followed by all other-watt bulbs (with a few exceptions for specialty bulbs) in 2014. It's been argued that this ban is destructive, at least economically speaking.