While I recognize many of these, I had no idea about the IBM Academic Operating System (a version of UNIX for their RT RISC workstations distinct from the norma

While I recognize many of these, I had no idea about the IBM Academic Operating System (a version of UNIX for their RT RISC workstations distinct from the normal IBM version AIX). There are just snippets of info about this OS on Wikipedia and other sites -- I wonder why IBM created it when they already had AIX.