<p>I have been reading carefully through the mediawiki documentation but I have not been able to find out how to create new groups. </p>

<p>When I look at Special:Userrights, I see only 3 groups : 
Bots, Sysops, Bureaycrats</p>

<p>I would like to create my own custom groups, so I can use some extensions like the <a href="http://www.mediawiki.org/wiki/Extension:Group_Based_Access_Control" rel="noreferrer">http://www.mediawiki.org/wiki/Extension:Group_Based_Access_Control</a>.</p>

<p>Can someone tell me how it's done, or point me to some documentation?</p>

I beleive I have found the answer, I just need to add the UserGroup and the permission to the wgGroupPermissions array in the LocalSettings.php file.
```
```
$wgGroupPermissions['TomatoUsers']['read']  = true;
$wgGroupPermissions['TomatoUsers']['edit']  = false;
```
```