Registry: differences between Shell Folders and User Shell Folders?

Please consider these two keys:

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders]

What is the main difference between these?

Say,
I've changed first the keys under Shell Folders and then under User Shell Folders.
It was only until I'd changed those under User Shell Folders (after restarting the machine) did the changes take place.
Shell Folders seem not to be taking effect at all.

mitchell65 said:

First off, have you created a registry backup? This is MOST IMPORTANT!! Dabbling with the registry can seriously damage your OS and should only be undertaken if you know exactly what you are doing!!!
Here's the definitive answer to your query:
Windows Registry - Wikipedia, the free encyclopedia

Yes, I did the backup first.
But could ya kindly point to me where my query is answered on the wiki page?

User Shell Folders

User Shell Folders: HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer

Description: The User Shell Folders subkey stores the paths to Windows Explorer folders for the current user of the computer.

Note: The entries in this subkey can appear in both the Shell Folders subkey and the User Shell Folders and in both HKEY_LOCAL_MACHINE and HKEY_CURRENT_USER. The entries that appear in user User Shell Folders take precedence over those in Shell Folders. The entries that appear in HKEY_CURRENT_USER take precedence over those in HKEY_LOCAL_MACHINE.

really interesting article brink, thanks for the link