VOS S4 was the most developed iteration of the Interreality/Virtual Object System project. Some new design concepts were then developed, which increased the flexibility and utility of VOS, and addressed some problems and difficulties discovered during S4.

Some parts of S4 as well as earlier documents are available for viewing here:

If you are interested in hearing more about VOS or Interreality in total (including server tools, the 3D user application client, the different types of objects developed for 3D graphics as well as other applications, and more), contact tetron at interreality dotorg or reed at interreality dotorg.