Before energy saving light bulbs were so readily available, we would purchase light bulbs based on how many watts or how much energy they used. With newer light bulbs you can achieve the same level of brightness for while using up to 80% less power. When shopping for bulbs today, look for lumens not watts. Light bulbs usually include a label on the packaging.
On the ‘Lighting Facts’ you will see how many lumens (the measure of brightness), the estimated yearly cost of energy to use this light bulb, the lifespan, and the color tint of the bulb. Warm is a yellowish color, while cool is more blue. You can see that in this example only 13 watts of energy are used, however, if you are used to using 60 watt bulb then this 800 lumens will provide the same amount of light using only 21.7% as much energy.
For more information on buying the right kind of bulb, or lumens-to-watts conversion, check out this informational video.