Softdisk Publishing UDF files

Softdisk was a publisher of diskmagazines and other software from the 1980s through the early 2000s, as well as a dialup Internet Service Provider (in the Shreveport, LA area) and web host in the late 1990s and early 2000s. It's perhaps best known as the place John Romero, John Carmack, and other founders of Id Software were working when they started their own game-making company as moonlighters.

Their programs used a wide variety of file formats (text-based and binary) for loading and saving data, but at one point in the 1990s some of its developers decided to attempt to standardize the internally-created file formats for future programs, leading to a format specification they termed "UDF" (Universal Data Format, or Uniform Data Format, or Uniform Data File?). There was an internal spec document (which I've unfortunately not been able to find a copy of yet).

(more description coming)