VMS (Virtual Memory System) is an operating system from the Digital Equipment Corporation (DEC) that runs in its older mid-range computers. VMS originated in 1979 as a new operating system for DEC’s new VAX computer, the successor to DEC’s PDP-11. … (OpenVMS is also the name now used on the VAX computer.)
A Virtual Machine (VM) is a compute resource that uses software instead of a physical computer to run programs and deploy apps. One or more virtual “guest” machines run on a physical “host” machine. … This means that, for example, a virtual MacOS virtual machine can run on a physical PC.