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 file format is used to transmit image data. It contains a set of images that can be linked to form an animation. It is used to store non-compressed bitmap images in 24-bit color created using MTV ray tracer.