Carbon footprint is the amount of energy, greenhouse gases (including carbon dioxide and methane) and waste that is generated to support the lifestyle of a country, group or individual.
Greenhouse gases are the gases in the atmosphere that produce the "greenhouse effect" and contribute to global warming and climate change.
Many of our daily activities, such as using electricity, driving a car, or disposing of waste cause greenhouse gas emissions. Together these emissions make up a carbon footprint.
So your carbon footprint a way to measure the environmental impact your lifestyle has. What is not necessary is wastage and degrading the environment just to sustain our lifestyle.
In summary, the largest producers of GHG emissions are all things that we can directly control and reduce if we make even small changes.