Rainwater is the primary source of fresh water globally and provides suitable conditions for diverse ecosystems. It also enables hydroelectric power and plant/crop irrigation. Rainwater contains salt, water, nitric acid, sulfuric acid, and carbon. It goes through the hydrological cycle of evaporation, condensation, precipitation, and infiltration/runoff. Evaporation turns water into vapor which rises and condenses into clouds. Rain falls from clouds through precipitation and infiltrates the ground or runs off via rivers/lakes back to the oceans to complete the cycle.