Metaformats
From Just Solve the File Format Problem
A metaformat (or meta format) is a generic low-level file format used as a basis for defining high-level file formats.
Whether a format is a metaformat is ultimately a judgment call. There are no definitive answers to questions like: What is the difference between a container format and a metaformat? Or a serialization format and a metaformat? Is CSV a metaformat, or is it a database format? Should TIFF and PDF be considered to be metaformats, given all the subformats of them that have been defined?
