They are enormously rich in energy and easily penetrate the body but in spite of this, we can neither see nor feel them: X-rays work in secret.
Because of their physical properties we owe important advances in medicine to them. Their ability to see through the body and make bone and tissue structures visible allows us to diagnose fractures or diseases without opening the body.
X-rays, artificially generated in an X-ray tube, are ionising like radioactive radiation and can impair the functions of body cells.
Therefore, the use of X-rays is subject to strict regulations because benefits and possible harmful effects, above all of X-ray examinations and radiotherapy, must be carefully weighed up.