All objects emit a certain amount of IR radiation, also known as blackbody radiation, as a function of their temperatures. Generally speaking, the hotter the object is, the more radiation it emits.

An IR camera is a device that creates images from IR radiation. Also known as a thermographic camera, an IR camera uses wavelengths longer than visible light to create images even in total darkness, similar to a regular camera that forms an image using visible light. še two main types of IR cameras are those with (1) cooled or (2) uncooled IR detectors.