Hi to everybody!
I am a brand new member and developer for WebSphere Commerce 7.0. 
I need any information or explanation about the roles in WSC.
I am using SupplierMarketplace as a base for further development.
I need to understand the concepts, but I am lost in the details.
As far as I can understand, the roles are defining, who can do and what on which resources.
So the available commands are part of the set which has subsets called Action Groups.
All the commands (JavaBeans) are provided with policies defining which Organization is the owner of that Action Group, and which Resource Group can be manipulated with these commands, if I don't miss the point.
And the resources are collected into Resource Groups.
Each and every user has a base Organization belonging to, and it can also have roles in other organization. An User can be a member of a Member Group.
What I don't understand: how this all comes together?

I would really appreciate any easy to understand explanation about this topic.
Thank you very much in advance!

Csaba