Discussion of everything related to the OS/380 family of operating systems (MVS/380, VM/380), the hardware it runs on (S/380), the software that emulates that hardware (Hercules/380), the applications that run on those operating systems (GCCMVS, PDPCLIB, BREX, DIFFUTILS) - both use of and design of all components, which are expected to mature together. Also maintenance and distribution of same. Also any of these products being used on their big brothers (z/OS and z/VM).