An X-ray machine is any machine that involves X-rays. It may consist of an X-ray generator and an X-ray detector. Examples include: ... Machines for computed tomography. Backscatter X-ray machines, used as "body scanners" in airport security.
An ultrasound machine makes images so that organs inside the body can be examined. The machine sends out high-frequency sound waves, which reflect off body structures. A computer receives the waves and uses them to create a picture.