J2.5:Access Control List
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Overview of ACL in Versions 
This section outlines the major ACL changes between versions 1.5 and 2.5 series (including 1.6 and 1.7). The table below summarizes the major changes from version 1.5.
| |
Version 1.5 | 2.5 series |
|---|---|---|
| Groups | 7 fixed groups (Public, Registered, Author, Editor, Publisher, Manager, Administrator, and Super-Administrator) | Unlimited user-defined Groups |
| Users & Groups | A User can be assigned to only one group | A User can be assigned to multiple groups |
| Access Levels | 3 fixed Access Levels (Public, Registered, Special) | Unlimited user-defined Access Levels |
| Access Levels & Groups | Relationship between Groups and Access Levels was fixed. | Groups are assigned to Access Levels. Any combination of Groups can be assigned to any Access Level. |
We see that in every case the ACL has been made much more flexible, with unlimited Groups and Access Levels, and the ability to assign one User to multiple Groups and any Groups to any Access Level.
