Carbon footprint is the measurement of how much CO2 a person's lifestyle releases to the atmosphere. It is averagely about 4 tons per person per year, while it is about 20 in the U.S., 10 in Europe, and 1 in India. The developed areas tend to have more carbon footprint by the activities e.g. constructions, cars, etc. There are ways to reduce uses of fossil fuels, for example, grow own food to reduce transport costs, not using filament lightbulbs which only 3% of the energy released is light, use washing machine when the clothes can full-filled with low-temperature setting, recycle unwanted materials, (raw material energy outweigh transportation of waste to recycle) and many more.