Creative Suite 6 (CS6) came out in 2012. It's legacy software now.
If your computer supports it and you want the latest & greatest features, you need CC 2017 not CS6.
As Nancy eluded to - none whatsoever.
In the CS6 days there used to be two versions - the extended versions added extra functions such as 3D, Stack Modes and Analysis functions.
Now there is only one version and it includes all the functions (and of course all those added since 2012)