Air conditioning is a technology that cools and dehumidifies indoor air to create a comfortable environment. It works by circulating refrigerant through a system of coils, absorbing heat from the air inside a building and releasing it outside. This process helps maintain a stable temperature, especially during hot weather. In addition to cooling, air conditioning systems can also improve indoor air quality by filtering out dust, allergens, and other pollutants. Many modern units come with programmable thermostats, allowing users to set specific temperatures and schedules for energy efficiency. Popular types of air conditioning include central air conditioning, window units, and portable air conditioners.