For over 25 years, the name VOS has referred to an operating system that is reliable, continuously available, and easy to use.  We did not take the decision to rename VOS lightly. The new name acknowledges another important trend has taken place over the last 10 years.  The software industry has gradually settled on just two major software development environments.  One is the Microsoft Windows environment. The other is the UNIX / Linux / POSIX environment.  As it happens, VOS can trace its lineage back to Multics, as can UNIX.  VOS and UNIX are sufficiently similar that we have been able to add a POSIX environment to VOS without much difficulty.

The POSIX standard is an “open” standard because an international committee of experts writes and maintains it. No single vendor controls it, as would be the case with a “closed”, or proprietary, system.

Since many different computer vendors provide execution environments that comply with the POSIX standard, you can be assured that software that you write that follows the standard will be portable across many different systems.  Similarly, the skills of your employees are also portable.

Our adoption of the POSIX standard has also enabled Stratus to offer a wide range of industry-standard software products on VOS.

We adopted the name OpenVOS, starting with Release 17.0, to emphasize these new capabilities, and to ensure that our VOS (now, OpenVOS) customers took full advantage of them.

For simplicity, we will continue to refer to versions of VOS prior to release 17.0 as “VOS”, even though they contain almost as much open technology as OpenVOS 17.0.