.dcm

DICOM stands for "Digital Imaging and Communications in Medicine." It is a standard medical imaging format used for storing and transferring medical images, such as X-rays, ultrasounds, CT scans, and MRIs.

Since DICOM is a standard format, DICOM images are recognized by multiple hardware devices and software programs. This makes it possible for doctors to transfer medical images between locations without having to worry about file format incompatibilities.