objects that we think of as being very cold, such as an ice cube, emit infrared. When an object is not quite hot enough to radiate visible light, it will emit most of its energy in the infrared.
Infrared light is even used to heat food sometimes - special lamps that emit thermal infrared waves are often used in fast food restaurants! Shorter, near infrared waves are not hot at all - in fact you cannot even feel them.
The higher the frequency of the radiation, the more damage it is likely to cause to the body: microwaves cause internal heating of body tissues. infrared radiation is felt as heat and causes skin burns.
Infrared waves have a frequency just under visible light and are used for many different things in households, military, and commercial uses. Infrared is also used for night vision goggles, infrared heating, and whether forecast.