Medical physics (also called biomedical physics, medical biophysics, applied physics in medicine, physics applications in medical science, radiological physics or hospital radio-physics) is, in general, the application of physics concepts, theories, and methods to medicine or healthcare. Medical physics departments may be found in hospitals or universities. Medical physics is generally split into two major subgroups, specifically radiation therapy and radiology. Medical physics of radiation therapy can involve work such as dosimetry, linac quality assurance, and brachytherapy. Medical physics of radiology involves medical imaging techniques such as magnetic resonance imaging, ultrasound, computed tomography, positron emission tomography, and x-ray.