Back in 1987, AT&T and Sun announced that the two companies were collaborating to release a new version of UNIX, combining the two most popular versions at the time – BSD and System V. This new UNIX version would be named UNIX System V Release 4 – SVR4.

In 1991, Sun announced that they were replacing their existing UNIX OS, SunOS, with a new version based on SVR4. SunOS was based on BSD and Sun were starting to run into problems with that variant, and so with an eye to the future Sun announced Solaris 2.

SunOS was then renamed Solaris 1, and each Solaris version was composed of the operating environment (Solaris 2.6, Solaris 7, Solaris 10) and it’s related kernel (SunOS 5.6, SunOS 5.7, SunOS 10). The reason for this odd branding was that Solaris would mean the complete operating environment, which included the window manager and other products.

Solaris now uses a common codebase for both SPARC and x86 versions. Previous versions had officially been ported by Sun to the PowerPC and Itanium processors. Solaris is now one of the most common UNIX versions, thanks to it’s power, scalability, and many new technologies Sun include with each release.

With the release of OpenSolaris, Sun have completed the process of open sourcing a powerful enterprise UNIX, allowing even the smallest Solaris consultancy to build a cost effective UNIX infrastructure.