KB wiki-5

I don't want the public to be able to edit my wiki or create accounts on the fly, how?

This is a setting in LocalSettings.php, the primary configuration file.

Add the following lines and you should be good.

$wgGroupPermissions['*']['edit'] = false;
$wgGroupPermissions['*']['createaccount'] = false;

These constrain the non-logged in users from editting pages, or creating accounts.