Regular light bulbs, or as otherwise known, incandescent light bulbs, produce light by passing electricity through a thin filament which becomes hot and glows, giving off the light we see. Incandescent light bulbs are less energy efficient than fluorescent light bulbs are, because much of the electrical energy is converted to heat instead of light. Fluorescent light bulbs, or lamps, produce light by passing electricity through a gas, causing it to glow. They are more energy efficient than regular (incandescent) light bulbs.
There is a difference sport ween the two in cost. Regular light bulbs will cost you about half the price that a flourescent light bulb will. But it is shown that flourescent light bulbs last up to 6 to 10 times longer than a regular light bulb. As well as lasting longer, flourescent light bulbs will also use less energy, making them the more energy efficient choice. If you replace 1/4 of your regular light bulbs with flourescent light bulbs, you can save around 50% on your energy/lighting bill.
If you look for light fixtures with an ENERGY STAR label from the Department of Energy (DOE) you can save both energy and money. According to the department of energy, by using just two ceiling-mounted fixtures and one ENERGY STAR torchiere in high-use areas can save you about $50 per year on your electric bill. ENERGY STAR fixtures must last 10,000 - 20,000 hours. This means, with regular use (i.e., 3.5 hours per day), you won't need to change the bulb for at least seven years.