This is an archive file used on Macintosh computers. It stores branched resources and data in the file system as one file. It includes the storage of fonts and convenient loading of data with Macintosh to the Internet to be transferred to other Mac devices. It’s used to import PostScript Type 1 program language data.
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 Today it has become obsolete and has been replaced by more flexible formats with DRM protection.