This is a format for presenting fonts in PDF files that was initially conceived to store symbols in the Japanese and Chinese languages because it had a 16-bit structure and allowed for more precise adjustment. CID expands the the potential for PostScript by supporting languages that do not have a left-to-right orientation, and by supporting even a vertical mode of orientation.
This format is used to store templates and designs in PageMaker 3. PT3 allows for a set of font descriptions, and for the layout and graphical elements to be stored in PostScript Type 3 format. This container is used as an editable file to meet publishing needs, and was created in a program for the PageMaker layout.