Infrared is a type of electromagnetic radiation that has longer wavelengths than visible light, making it invisible to the human eye. It is commonly associated with heat, as objects emit infrared radiation when they are warm. For example, when you feel warmth from the sun or a heater, you are experiencing infrared radiation. Infrared technology is widely used in various applications, such as remote controls for televisions and night vision devices. It also plays a crucial role in astronomy, allowing scientists to study celestial objects that emit infrared light, revealing information about their temperature and composition.