Introduction Carbon is one of the most important elements and it is a major constituent of life on Earth. This element is the primary chemical constituent of most living matter and it is found in large proportions on our planet. At any given time, carbon is stored in various reservoirs on the planet. Some of the major global reservoirs that store carbon include organic compounds, atmospheric carbon dioxide, the soil, rocks, and the ocean. Carbon does not stay in any of these reservoirs permanently and it moves between the various stores in the process referred to as the carbon cycle. Over a time scale that extends to thousands of years, the atmosphere, land, and oceans exchange huge quantities of carbon through biological, physical, and chemical means. An understanding of the carbon cycle will assist in the understanding of the Earth’s climatic history. This paper will discuss the carbon cycle, which is the continuous movement of carbon atoms through different paths, with a focus on the two major divisions of the process and the human impact on the carbon cycle. Defining the Carbon Cycle The carbon cycle is the process through which carbon moves between the different carbon reservoirs. These reservoirs exist in land and water-based systems. Arwyn and Broll (2012) reveal that through its many forms, carbon can move between the “atmosphere, hydrosphere, biosphere, pedosphere, and lithosphere” (p.119). The land surface, soil, the atmosphere, water bodies, and vegetation all act as carbon stores. Each of these carbon stores can be regarded as a sink and a source. The storage pools are considered sinks since they can take the carbon from the atmosphere and hold it (Folger, 2009). The storage pools are also considered carbon sources since they release carbon into the atmosphere through various chemical processes. Arwyn and Broll (2012) note that the carbon cycle is the natural process through which carbon atoms are recycled. For example, the same carbon atoms produced from burning wood many years ago could become a part of a plant through photosynthesis and later became a part of a human being who consumes the plant. The carbon cycle is responsible for keeping the Earth in a stable climatic state. The carbon exchange between the various sources and skins ensures that the carbon contained in the atmosphere is at a healthy level. The carbon cycle can be divided into biological and geological cycles. The Biological Carbon Cycle This is the circulation of carbon between land-based and water-based systems. These systems comprise “the ocean, the atmosphere, the soil, and the biosphere” (Levin, 2009, p.43). This is collectively referred to as the surface reservoirs and the rocks are not involved. This fast carbon cycle is dependent on the biologically catalyzed reduction of inorganic carbon to form organic matter. Levin (2009) reveals that most of this carbon is reconverted to inorganic carbon through respiratory metabolism. The biological carbon cycle takes a relatively short duration of time compared to the geological carbon cycle. The movement of carbon from different pathways can take place within a few days or millennia. In the carbon exchange between the land and