Radiology, or diagnostic imaging, involves various tests like x-rays, MRIs, CT scans, and ultrasounds to visualize the inside of the body for diagnosing diseases such as cancer. Discovered by Wilhelm Rontgen in 1895, radiology has rapidly advanced and now plays a crucial role in medical care, with radiologists interpreting imaging tests and performing interventional procedures. The field consists of diagnostic radiology, interventional radiology, and radiation radiology, each serving specific medical purposes.