A desert cooler, also known as an evaporative cooler, is a device used to cool air through the evaporation of water. It works by drawing warm air through water-saturated pads, which cools the air before it is circulated into a room. This method is particularly effective in dry climates, where humidity levels are low, making it a popular choice in areas like the Southwestern United States. Desert coolers are energy-efficient and environmentally friendly compared to traditional air conditioning systems. They require less electricity and use water as the primary cooling agent. However, they are less effective in humid conditions, as high moisture levels can hinder the evaporation process.