Water is an integral part of Earth’s structure and plays a unique role in Earth’s processes. The water cycle is central to life on Earth and connects Earth systems. Life processes depend on water. Both the quantity and quality of water contribute to the sustainability of life on Earth. Because it is of great importance to conscioususe of existing resources, to make water conservation, to prevent water pollution, to recognize the importance of water for the continuation of clean water that we can inherit from future generations.