Carbon is important because it one of the main building blocks of most matter on Earth. It can bond with any other element, including itself. Most of the carbon on Earth is stored in the atmosphere. It is taken in by plants through photosynthesis and then animals get it from eating the plants. It is released back into the atmosphere from plants and animals through respiration. It can also be stored in the ground when decomposers break down dead organisms. It can be locked in the environment this way by being made into a fossil fuel, like coal or oil. Human activities that can disrupt this cycle are, as shown above, the burning of these fossil fuels and releasing more carbon into the air. An interesting fact about carbon is that most people think that most of the carbon stored in the ground is stored as fossil fuels, but that is only a very small percentage of the carbon stored.
