Thanks! Didn't recognize that as an 'about' link, not that familiar with the pre-web culture, I guess.

File_id.diz isn’t pre-web, despite its origins in BBSs - it’s an archive descriptor, most commonly associated with the warez scene. I guess it largely died along with dialup, when multipart archives stopped being a necessity for large downloads.

I've seen file_id.diz before, but any insight as to what 'DIZ' is? I can figure out what, e.g. an .nfo file is, but I'm having trouble with .diz.

Wikipedia even has an article on these files: it says, ‘FILE_ID stands for "file identification". DIZ stands for Description In Zipfile’.

https://en.wikipedia.org/wiki/FILE_ID.DIZ