A carbon footprint is a measure of the impact human activities have on the environment in terms of the amount of greenhouse gases produced, measured in units of carbon dioxide. Carbon footprint is made up of the sum of two parts, the direct / primary footprint and the indirect / secondary footprint. The primary footprint is a measure of our direct emissions of CO2 from the burning of fossil fuels including domestic energy consumption and transportation (e.g. car and plane). The secondary footprint is a measure of the indirect CO2 emissions from the whole lifecycle of products we use – those associated with their manufacture and eventual breakdown >