A mainframe OS, designed for multiple users. While a similar concept to UNIX the commands and applications are all very different.
Virtual Memory System. The operating system for a long line of DEC computers, including the CIRCA VAX's and the Biostat MicroVax. VMS is a mature, full-featured operating system with multi-tasking, multi-processing and network communications.
Acronym for Virtual Memory System, an operating system designed for Digital's 32-bit VAX (Virtual Address eXtension) computers. Like UNIX, it is frequently used in server and workstation applications.