Updated: Feb 19
In MediaWiki, users that visit your site and perform various actions belong to one or more user groups. A group has rights/permissions that specify what the users in that group are allowed to do on the site. MediaWiki comes preconfigured with some default groups. Custom groups can be created, and permissions can be changed by inserting some code in the LocalSettings.php file of your MediaWiki.
Registered users can then be assigned to other user groups by other users with the permissions to do so, and in this way, they can be allowed to do even more things.
MediaWiki User Groups
Default MediaWiki groups are:
* – all visitors, including anonymous ones
user – registered users
sysop – administrators with a lot of power
bureaucrat – a special group with the important right to assign users to groups.
There are some other built-in groups (bots, interface administrators, etc). Other groups and permissions can be added by extensions. You can read more about user groups here.

Manage Wiki User Rights
To add or remove users from groups go to Special:UserRights. To do so, one must belong to the bureaucrats group or must be given appropriate permissions in the config file.

Wiki User Rights Tips
There is a section Users Rights on the special pages (usually located in Tools menu).
If you want to see a list of the registered users and find a particular user, there's a special page on the site that lists all users: User list / Special:ListUsers
To view what the currently existing user groups are an what the permissions for each group are, use User group rights / Special:ListGroupRights
Block Wiki Users
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