[Zope-CMF] instructions as to how I can set the security mechanisms

[Norman Khine]

Hello,
Are there any instructions as to how I can set the security mechanisms for a
cmf. In perticular I would like to understand the mechanism which controls
what a Member can add to the portal, for example:

If I create the following roles:

News_Editor - this person can only add NewsItems
Document_Editor - this person can only add DocumentItems
Members - they can only add folders, images, files and URL links

Many thanks

Norman