Water supply refers to the application system that provides domestic water and direct drinking water to buildings or other facilities. This system requires a series of pipes, fittings, pumping stations, water tanks, and controls to ensure that water is conveyed, stored, and distributed to where it is needed, such as residential buildings, commercial buildings, and industrial facilities. In addition, the design and operation of water supply systems need to take into account factors such as water resource sustainability, environmental protection, energy consumption, and safety. Safe and environmentally friendly pipes and fittings are necessary to meet users' long-term needs for water quality and quantity.