Radiology is the branch or specialty of medicine that deals with the study and application of imaging technology like x-ray and radiation to diagnosing and treating disease. It is still the first study ordered in evaluation of the lungs, heart and skeleton because of its wide availability, speed and relative low cost.
The acquisition of medical imaging is usually carried out by the radiographer or radiologic technologist. Outside of the medical field (in comparison), radiology also encompasses the examination of the inner structure of objects using X-rays or other penetrating radiation. CT imaging uses X-rays in conjunction with computing algorithms to image the body. Medical ultrasonography uses ultrasound (high-frequency sound waves) to visualize soft tissue structures in the body in real time.
Plain radiography was the only imaging modality available during the first 50 years of radiology.