OpenVMS

OpenVMS is a multi-user, multiprocessing, virtual memory-based, general-purpose computer operating system developed by DigitalEquipmentCorporation? (DEC) and initially released as "VAX/VMS" in 1977 for the VAX-11 minicomputer. The operating system was ported for the DEC Alpha CPU in 1992 (at which time it was renamed "OpenVMS"), and ported for the Intel Itanium CPU in 2001. OpenVMS is currently marketed as an operating system option for some models of HewlettPackard? Integrity servers.