Black Body

Black color body absorbs much of the light (visible range of electromagnetic radiation) that falls on it and converts to heat energy. Conversely balackbody quickly converts much of the heat energy to electromagnetic radiation.

It is interesting to note that wearing black color cloths in dark room makes you cooler. The heat from body transferred to the black color cloths and it quickly converts the heat to electromagnetic radiation.

At room temperature black-body radiates infrared radiation. If temperature crosses few hundred degrees Celsius, black-body starts emitting red light. If temperature increases furthur it can emit higher frequencies like blue - violet radiation and can go to the extent where it can emit ultraviolet radiation.