Notable major player here was IBM on the AS/400, you had libraries containing objects of various types (such as PGM/Program, FILE/'file', *DTAQ/Data Queue, etc)

Notable major player here was IBM on the AS/400, you had libraries containing objects of various types (such as PGM/Program, FILE/'file', *DTAQ/Data Queue, etc). 'file' objects were effectively database tables, and even things like source code for programs were stored as such. Eventually IBM added the IFS (integrated file system) to provide a more traditional POSIX-adjacent filesystem that was in fact just a bunch of bits, and it feels weird and out of place with the rest of the system as a result.