This is an international format that was developed for the purpose of storing images of the body taken with medical imaging equipment. It includes magnetic resonance and computer tomography images, ultrasound images and fluoroscopy, as well as images taken with other medical imaging equipment. DCM also stores patient information in the metadata, which form part of a single file.
This format was used for storing databases on the Pegasus and Palm PDA devices. Besides images, PDB allowed you to store tables, maps, e-books, and other data in a structured way. Today it has become obsolete and has been replaced by more flexible formats with DRM protection.