Whats the difference between normal Photoshop and the Extended version?

From first thought my initial idea would be that the extended one has all of the normal features plus extras...

am i correct.

thanks in advance :D
------Extra question - CS4 Or CS5

Extended includes additional features for 3D and motion based content, see link below for comparison.

CS5 is now the current version from Adobe, to buy CS4 you would need to look online on Ebay, Amazon or similar.

http://www.adobe.com/products/photoshop/compare/

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