Although disagreement exists on what is actually being observed, Kirlian photography involves taking a "picture" of the putative energy field emitted by the body. Observational differences exist before and after certain bioenergetic therapies; however, it's unclear what type of "radiation" is being measured. In complementary and alternative medicine, the electromagnetic field surrounding a patient is often referred to as that subject's aura. Other approaches to detecting energy fields include aura imaging and gas discharge visualization.
(SOURCE: NCCAM, National Institutes of Health)