Evaporative coolers, also known as swamp coolers, are devices that cool air through the evaporation of water. They work by drawing warm air through water-saturated pads, which cools the air before it is circulated into a space. This process is energy-efficient and environmentally friendly, making it a popular choice in dry, arid climates. These coolers are typically less expensive to operate than traditional air conditioning systems. They require a constant supply of water and work best in low-humidity areas, as high humidity can reduce their cooling effectiveness. Regular maintenance, such as cleaning the pads, is essential for optimal performance.