Radiology is a medical specialty that employs the use of imaging to both diagnose and treat disease visualised within the human body. Radiologists use an array of imaging technologies (such as x-ray radiography, ultrasound, computed tomography (CT), nuclear medicine, positron emission tomography (PET) and magnetic resonance imaging (MRI) to diagnose or treat diseases. Interventional radiology is the performance of (usually minimally invasive) medical procedures with the guidance of imaging technologies. The acquisition of medical imaging is usually carried out by the radiographer or radiologic technologist.

The following imaging modalities are used in the field of diagnostic radiology:

Radiographs (or roentgenographs, named after the discoverer of x-rays, Wilhelm Conrad Röntgen) are produced by transmitting x-rays through a patient. A capture device then converts x-rays into visible light which then forms an image for review and diagnosis. The original - and a still common imaging procedure uses silver-impregnated films.