There is a limited global supply of freshwater on Earth. Water moves through the water cycle by evaporating from bodies of water and the land, condensing in the atmosphere, and precipitating back down as rain or snow. This precipitation runs off into rivers and streams or soaks into the ground to replenish groundwater. Climate is influenced by factors like latitude, altitude, proximity to bodies of water, and ocean currents, which determine temperature and precipitation patterns in different regions of the world. The main climate types are tropical, temperate, and polar.