Carbon footprint is a measure of how much fossil fuel intensity is involved in your life. It also can be taken from the standpoint of the carbon dioxide you breathe out of your body. I understand it takes something like 15 trees to support a single individual’s ability to breathe because trees take in carbon dioxide and put out oxygen. So if we’re going to take in oxygen, there has to be a source of it. Fifteen trees for every person breathing, and so, you know, the question that can be asked is, do you own your own trees or are you using someone else’s? Similarly, when we use fossil fuel, it takes the trees, soaking in carbon dioxide, to pull that out of the air. And so your carbon footprint is how much excess carbon you’re putting into the air.