Very big difference between those 2.
3D Studio Max is an all-in-one 3D software, that means you can model absolutely anything, animate models and/or create animations, texture them and what not else.
3D World Studio was made for easy “world” creation. That means you can’t really model extra good models or make animations. 3DWS was made for adding different models in 1 scene and then exporting them as “world” models thus making it easy to put landscape and things on it very fast.
But in short, 3DSM is a professional all-in-one 3D package (that’s why it’s so expensive) while 3DWS is a software that is aimed for doing just 1 part of that all-in-one thing 3DSM can do (that’s why 3DWS is cheaper).
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