The Hydrologic Cycle, or Water Cycle, is a model or representation of the large-scale movements of water on Earth. Water evaporates into the atmosphere, and then condenses and falls as precipitation. Some precipitation falls dirctly on water bodies such as rivers, streams, lakes, or the ocean. Precipitation that falls on land is carried to water bodies by runoff. Although any water can evaporate, most of the Earth's water is in the oceans, so it is primarily from the oceans that evaporation occurs. This is a very simplistic model. The model on the previous page is more complex, though it too is a simple representation of a very complex system.