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 developed to simplify use of Type1-fonts in some software. It’s 8-bit and so it’s quickly processed by programs and it has a compact structure. PFB contains additional metadata. Besides the storage of system fonts, a good example of its use is its application in AutoCAD to create font files with compilation.