A SuperUser is a user with the permission to do wiki-wide operations like:

(!) Do not confuse a superuser with someone having the "admin" ACL right. The "admin" ACL right just means to be able to set/change/remove ACLs on some or all pages, while being superuser means to be able to do the above mentioned stuff - globally.

The people being superuser need to be much more trusted (than people with "admin" ACL right) due to this - usually the ones who install the wiki put themselves into the superuser list in the wiki config (see HelpOnConfiguration).

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