Open cooling towers are structures used to remove heat from water in industrial processes or HVAC systems. They work by allowing warm water to flow over fill material, where it is exposed to air. As the water evaporates, it cools down, and the cooled water is then recirculated back into the system. These towers are typically designed to maximize air and water contact, enhancing the cooling process. They are often found in power plants, chemical processing facilities, and large commercial buildings. Proper maintenance is essential to prevent issues like algae growth and ensure efficient operation.