Virtual Memory System, a multi-user, multitasking, virtual memory operating system that runs on the VAX and Alpha lines of minicomputers and workstations, originally developed by Digital Equipment Corporation. VMS was introduced in 1977 and the first customer version shipped in 1978 along with the first VAX minicomputer. The operating system was renamed to OpenVMS in the early 1990's. In 1998, Compaq acquired DEC. Compaq announced the port of the OS to the Itanium Processor Family in 2001. Subsequently, Hewlett Packard aquired Compaq and has maintained roadmaps for the OS, committing to the Itanium port, and they successfully demonstrated OpenVMS booted on an Itanium in early 2003. FreeVMS is an initiative to rewrite the OpenVMS operating system and associated utilities under a public license.