Yes, humans give off radiation. Humans give off mostly infrared radiation, which is electromagnetic radiation with a frequency lower than visible light. This effect is not unique to humans. All objects with a non-zero temperature give off thermal radiation. And because a temperature of exactly absolute zero is physically impossible, all objects give off thermal radiation. We have to be careful here. Thermal radiation is not the exact same thing as infrared radiation. "Thermal radiation" is all the electromagnetic waves given off by an object because of its temperature, and includes radio waves, infrared waves, and even visible light. Infrared waves are only one part of thermal radiation. The two tend to get confused because most of the thermal radiation is infrared radiation for temperatures that are comfortable to humans. As an object gets hotter, the peak of its thermal radiation shifts to higher frequencies. The sun is hot enough that most of its thermal radiation is em...
