What is the difference between VMS and OpenVMS?
VMS and OpenVMS are two names for the same operating system. Originally, the operating system was called VAX-11/VMS; it changed to VAX/VMS at around VAX/VMS V2.0. When the VMS operating system was ported to the Alpha platform, it was renamed OpenVMS, for both VAX and Alpha (and for the Itanium Processor Family), in part to signify the high degree of support for industry standards such as POSIX, which provides many features of UNIX systems. For those versions with POSIX, an OpenVMS license allows you to install and run POSIX for OpenVMS at no additional charge; all you need is the media and documentation which can be found on the Consolidated Distribution and On-Line Documentation CD-ROMs. Support for the POSIX package on more recent OpenVMS releases is not available, various parts of POSIX such as calls from the API are being integrated more directly into OpenVMS. For more information on POSIX for VMS see question SOFT2 What became confusing is that the OpenVMS name was introduced firs
